1 //===--- MultiplexExternalSemaSource.h - External Sema Interface-*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 //  This file defines ExternalSemaSource interface, dispatching to all clients
10 //
11 //===----------------------------------------------------------------------===//
12 #ifndef LLVM_CLANG_SEMA_MULTIPLEXEXTERNALSEMASOURCE_H
13 #define LLVM_CLANG_SEMA_MULTIPLEXEXTERNALSEMASOURCE_H
14 
15 #include "clang/Sema/ExternalSemaSource.h"
16 #include "clang/Sema/Weak.h"
17 #include "llvm/ADT/SmallVector.h"
18 #include <utility>
19 
20 namespace clang {
21 
22   class CXXConstructorDecl;
23   class CXXRecordDecl;
24   class DeclaratorDecl;
25   struct ExternalVTableUse;
26   class LookupResult;
27   class NamespaceDecl;
28   class Scope;
29   class Sema;
30   class TypedefNameDecl;
31   class ValueDecl;
32   class VarDecl;
33 
34 
35 /// An abstract interface that should be implemented by
36 /// external AST sources that also provide information for semantic
37 /// analysis.
38 class MultiplexExternalSemaSource : public ExternalSemaSource {
39   /// LLVM-style RTTI.
40   static char ID;
41 
42 private:
43   SmallVector<ExternalSemaSource *, 2> Sources;
44 
45 public:
46   /// Constructs a new multiplexing external sema source and appends the
47   /// given element to it.
48   ///
49   ///\param[in] S1 - A non-null (old) ExternalSemaSource.
50   ///\param[in] S2 - A non-null (new) ExternalSemaSource.
51   ///
52   MultiplexExternalSemaSource(ExternalSemaSource *S1, ExternalSemaSource *S2);
53 
54   ~MultiplexExternalSemaSource() override;
55 
56   /// Appends new source to the source list.
57   ///
58   ///\param[in] Source - An ExternalSemaSource.
59   ///
60   void AddSource(ExternalSemaSource *Source);
61 
62   //===--------------------------------------------------------------------===//
63   // ExternalASTSource.
64   //===--------------------------------------------------------------------===//
65 
66   /// Resolve a declaration ID into a declaration, potentially
67   /// building a new declaration.
68   Decl *GetExternalDecl(uint32_t ID) override;
69 
70   /// Complete the redeclaration chain if it's been extended since the
71   /// previous generation of the AST source.
72   void CompleteRedeclChain(const Decl *D) override;
73 
74   /// Resolve a selector ID into a selector.
75   Selector GetExternalSelector(uint32_t ID) override;
76 
77   /// Returns the number of selectors known to the external AST
78   /// source.
79   uint32_t GetNumExternalSelectors() override;
80 
81   /// Resolve the offset of a statement in the decl stream into
82   /// a statement.
83   Stmt *GetExternalDeclStmt(uint64_t Offset) override;
84 
85   /// Resolve the offset of a set of C++ base specifiers in the decl
86   /// stream into an array of specifiers.
87   CXXBaseSpecifier *GetExternalCXXBaseSpecifiers(uint64_t Offset) override;
88 
89   /// Resolve a handle to a list of ctor initializers into the list of
90   /// initializers themselves.
91   CXXCtorInitializer **GetExternalCXXCtorInitializers(uint64_t Offset) override;
92 
93   ExtKind hasExternalDefinitions(const Decl *D) override;
94 
95   /// Find all declarations with the given name in the
96   /// given context.
97   bool FindExternalVisibleDeclsByName(const DeclContext *DC,
98                                       DeclarationName Name) override;
99 
100   /// Ensures that the table of all visible declarations inside this
101   /// context is up to date.
102   void completeVisibleDeclsMap(const DeclContext *DC) override;
103 
104   /// Finds all declarations lexically contained within the given
105   /// DeclContext, after applying an optional filter predicate.
106   ///
107   /// \param IsKindWeWant a predicate function that returns true if the passed
108   /// declaration kind is one we are looking for.
109   void
110   FindExternalLexicalDecls(const DeclContext *DC,
111                            llvm::function_ref<bool(Decl::Kind)> IsKindWeWant,
112                            SmallVectorImpl<Decl *> &Result) override;
113 
114   /// Get the decls that are contained in a file in the Offset/Length
115   /// range. \p Length can be 0 to indicate a point at \p Offset instead of
116   /// a range.
117   void FindFileRegionDecls(FileID File, unsigned Offset,unsigned Length,
118                            SmallVectorImpl<Decl *> &Decls) override;
119 
120   /// Gives the external AST source an opportunity to complete
121   /// an incomplete type.
122   void CompleteType(TagDecl *Tag) override;
123 
124   /// Gives the external AST source an opportunity to complete an
125   /// incomplete Objective-C class.
126   ///
127   /// This routine will only be invoked if the "externally completed" bit is
128   /// set on the ObjCInterfaceDecl via the function
129   /// \c ObjCInterfaceDecl::setExternallyCompleted().
130   void CompleteType(ObjCInterfaceDecl *Class) override;
131 
132   /// Loads comment ranges.
133   void ReadComments() override;
134 
135   /// Notify ExternalASTSource that we started deserialization of
136   /// a decl or type so until FinishedDeserializing is called there may be
137   /// decls that are initializing. Must be paired with FinishedDeserializing.
138   void StartedDeserializing() override;
139 
140   /// Notify ExternalASTSource that we finished the deserialization of
141   /// a decl or type. Must be paired with StartedDeserializing.
142   void FinishedDeserializing() override;
143 
144   /// Function that will be invoked when we begin parsing a new
145   /// translation unit involving this external AST source.
146   void StartTranslationUnit(ASTConsumer *Consumer) override;
147 
148   /// Print any statistics that have been gathered regarding
149   /// the external AST source.
150   void PrintStats() override;
151 
152   /// Retrieve the module that corresponds to the given module ID.
153   Module *getModule(unsigned ID) override;
154 
155   /// Perform layout on the given record.
156   ///
157   /// This routine allows the external AST source to provide an specific
158   /// layout for a record, overriding the layout that would normally be
159   /// constructed. It is intended for clients who receive specific layout
160   /// details rather than source code (such as LLDB). The client is expected
161   /// to fill in the field offsets, base offsets, virtual base offsets, and
162   /// complete object size.
163   ///
164   /// \param Record The record whose layout is being requested.
165   ///
166   /// \param Size The final size of the record, in bits.
167   ///
168   /// \param Alignment The final alignment of the record, in bits.
169   ///
170   /// \param FieldOffsets The offset of each of the fields within the record,
171   /// expressed in bits. All of the fields must be provided with offsets.
172   ///
173   /// \param BaseOffsets The offset of each of the direct, non-virtual base
174   /// classes. If any bases are not given offsets, the bases will be laid
175   /// out according to the ABI.
176   ///
177   /// \param VirtualBaseOffsets The offset of each of the virtual base classes
178   /// (either direct or not). If any bases are not given offsets, the bases will
179   /// be laid out according to the ABI.
180   ///
181   /// \returns true if the record layout was provided, false otherwise.
182   bool
183   layoutRecordType(const RecordDecl *Record,
184                    uint64_t &Size, uint64_t &Alignment,
185                    llvm::DenseMap<const FieldDecl *, uint64_t> &FieldOffsets,
186                  llvm::DenseMap<const CXXRecordDecl *, CharUnits> &BaseOffsets,
187                  llvm::DenseMap<const CXXRecordDecl *,
188                                 CharUnits> &VirtualBaseOffsets) override;
189 
190   /// Return the amount of memory used by memory buffers, breaking down
191   /// by heap-backed versus mmap'ed memory.
192   void getMemoryBufferSizes(MemoryBufferSizes &sizes) const override;
193 
194   //===--------------------------------------------------------------------===//
195   // ExternalSemaSource.
196   //===--------------------------------------------------------------------===//
197 
198   /// Initialize the semantic source with the Sema instance
199   /// being used to perform semantic analysis on the abstract syntax
200   /// tree.
201   void InitializeSema(Sema &S) override;
202 
203   /// Inform the semantic consumer that Sema is no longer available.
204   void ForgetSema() override;
205 
206   /// Load the contents of the global method pool for a given
207   /// selector.
208   void ReadMethodPool(Selector Sel) override;
209 
210   /// Load the contents of the global method pool for a given
211   /// selector if necessary.
212   void updateOutOfDateSelector(Selector Sel) override;
213 
214   /// Load the set of namespaces that are known to the external source,
215   /// which will be used during typo correction.
216   void
217   ReadKnownNamespaces(SmallVectorImpl<NamespaceDecl*> &Namespaces) override;
218 
219   /// Load the set of used but not defined functions or variables with
220   /// internal linkage, or used but not defined inline functions.
221   void ReadUndefinedButUsed(
222       llvm::MapVector<NamedDecl *, SourceLocation> &Undefined) override;
223 
224   void ReadMismatchingDeleteExpressions(llvm::MapVector<
225       FieldDecl *, llvm::SmallVector<std::pair<SourceLocation, bool>, 4>> &
226                                             Exprs) override;
227 
228   /// Do last resort, unqualified lookup on a LookupResult that
229   /// Sema cannot find.
230   ///
231   /// \param R a LookupResult that is being recovered.
232   ///
233   /// \param S the Scope of the identifier occurrence.
234   ///
235   /// \return true to tell Sema to recover using the LookupResult.
236   bool LookupUnqualified(LookupResult &R, Scope *S) override;
237 
238   /// Read the set of tentative definitions known to the external Sema
239   /// source.
240   ///
241   /// The external source should append its own tentative definitions to the
242   /// given vector of tentative definitions. Note that this routine may be
243   /// invoked multiple times; the external source should take care not to
244   /// introduce the same declarations repeatedly.
245   void ReadTentativeDefinitions(SmallVectorImpl<VarDecl*> &Defs) override;
246 
247   /// Read the set of unused file-scope declarations known to the
248   /// external Sema source.
249   ///
250   /// The external source should append its own unused, filed-scope to the
251   /// given vector of declarations. Note that this routine may be
252   /// invoked multiple times; the external source should take care not to
253   /// introduce the same declarations repeatedly.
254   void ReadUnusedFileScopedDecls(
255                         SmallVectorImpl<const DeclaratorDecl*> &Decls) override;
256 
257   /// Read the set of delegating constructors known to the
258   /// external Sema source.
259   ///
260   /// The external source should append its own delegating constructors to the
261   /// given vector of declarations. Note that this routine may be
262   /// invoked multiple times; the external source should take care not to
263   /// introduce the same declarations repeatedly.
264   void ReadDelegatingConstructors(
265                           SmallVectorImpl<CXXConstructorDecl*> &Decls) override;
266 
267   /// Read the set of ext_vector type declarations known to the
268   /// external Sema source.
269   ///
270   /// The external source should append its own ext_vector type declarations to
271   /// the given vector of declarations. Note that this routine may be
272   /// invoked multiple times; the external source should take care not to
273   /// introduce the same declarations repeatedly.
274   void ReadExtVectorDecls(SmallVectorImpl<TypedefNameDecl*> &Decls) override;
275 
276   /// Read the set of potentially unused typedefs known to the source.
277   ///
278   /// The external source should append its own potentially unused local
279   /// typedefs to the given vector of declarations. Note that this routine may
280   /// be invoked multiple times; the external source should take care not to
281   /// introduce the same declarations repeatedly.
282   void ReadUnusedLocalTypedefNameCandidates(
283       llvm::SmallSetVector<const TypedefNameDecl *, 4> &Decls) override;
284 
285   /// Read the set of referenced selectors known to the
286   /// external Sema source.
287   ///
288   /// The external source should append its own referenced selectors to the
289   /// given vector of selectors. Note that this routine
290   /// may be invoked multiple times; the external source should take care not
291   /// to introduce the same selectors repeatedly.
292   void ReadReferencedSelectors(SmallVectorImpl<std::pair<Selector,
293                                               SourceLocation> > &Sels) override;
294 
295   /// Read the set of weak, undeclared identifiers known to the
296   /// external Sema source.
297   ///
298   /// The external source should append its own weak, undeclared identifiers to
299   /// the given vector. Note that this routine may be invoked multiple times;
300   /// the external source should take care not to introduce the same identifiers
301   /// repeatedly.
302   void ReadWeakUndeclaredIdentifiers(
303            SmallVectorImpl<std::pair<IdentifierInfo*, WeakInfo> > &WI) override;
304 
305   /// Read the set of used vtables known to the external Sema source.
306   ///
307   /// The external source should append its own used vtables to the given
308   /// vector. Note that this routine may be invoked multiple times; the external
309   /// source should take care not to introduce the same vtables repeatedly.
310   void ReadUsedVTables(SmallVectorImpl<ExternalVTableUse> &VTables) override;
311 
312   /// Read the set of pending instantiations known to the external
313   /// Sema source.
314   ///
315   /// The external source should append its own pending instantiations to the
316   /// given vector. Note that this routine may be invoked multiple times; the
317   /// external source should take care not to introduce the same instantiations
318   /// repeatedly.
319   void ReadPendingInstantiations(
320      SmallVectorImpl<std::pair<ValueDecl*, SourceLocation> >& Pending) override;
321 
322   /// Read the set of late parsed template functions for this source.
323   ///
324   /// The external source should insert its own late parsed template functions
325   /// into the map. Note that this routine may be invoked multiple times; the
326   /// external source should take care not to introduce the same map entries
327   /// repeatedly.
328   void ReadLateParsedTemplates(
329       llvm::MapVector<const FunctionDecl *, std::unique_ptr<LateParsedTemplate>>
330           &LPTMap) override;
331 
332   /// Read the set of decls to be checked for deferred diags.
333   ///
334   /// The external source should append its own potentially emitted function
335   /// and variable decls which may cause deferred diags. Note that this routine
336   /// may be invoked multiple times; the external source should take care not to
337   /// introduce the same declarations repeatedly.
338   void ReadDeclsToCheckForDeferredDiags(
339       llvm::SmallSetVector<Decl *, 4> &Decls) override;
340 
341   /// \copydoc ExternalSemaSource::CorrectTypo
342   /// \note Returns the first nonempty correction.
343   TypoCorrection CorrectTypo(const DeclarationNameInfo &Typo,
344                              int LookupKind, Scope *S, CXXScopeSpec *SS,
345                              CorrectionCandidateCallback &CCC,
346                              DeclContext *MemberContext,
347                              bool EnteringContext,
348                              const ObjCObjectPointerType *OPT) override;
349 
350   /// Produces a diagnostic note if one of the attached sources
351   /// contains a complete definition for \p T. Queries the sources in list
352   /// order until the first one claims that a diagnostic was produced.
353   ///
354   /// \param Loc the location at which a complete type was required but not
355   /// provided
356   ///
357   /// \param T the \c QualType that should have been complete at \p Loc
358   ///
359   /// \return true if a diagnostic was produced, false otherwise.
360   bool MaybeDiagnoseMissingCompleteType(SourceLocation Loc,
361                                         QualType T) override;
362 
363   /// LLVM-style RTTI.
364   /// \{
365   bool isA(const void *ClassID) const override {
366     return ClassID == &ID || ExternalSemaSource::isA(ClassID);
367   }
368   static bool classof(const ExternalASTSource *S) { return S->isA(&ID); }
369   /// \}
370 };
371 
372 } // end namespace clang
373 
374 #endif
375