DeclBase.h revision 72c3f314d92d65c050ee1c07b7753623c044d6c7 
1//===-- DeclBase.h - Base Classes for representing 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 Decl and DeclContext interfaces.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_CLANG_AST_DECLBASE_H
15#define LLVM_CLANG_AST_DECLBASE_H
16
17#include "clang/AST/Attr.h"
18#include "clang/AST/Type.h"
19#include "clang/Basic/SourceLocation.h"
20
21namespace clang {
22class DeclContext;
23class TranslationUnitDecl;
24class NamespaceDecl;
25class ScopedDecl;
26class FunctionDecl;
27class CXXRecordDecl;
28class EnumDecl;
29class ObjCMethodDecl;
30class ObjCInterfaceDecl;
31class BlockDecl;
32
33/// Decl - This represents one declaration (or definition), e.g. a variable,
34/// typedef, function, struct, etc.
35///
36class Decl {
37public:
38  enum Kind {
39    // This lists the concrete classes of Decl in order of the inheritance
40    // hierarchy.  This allows us to do efficient classof tests based on the
41    // enums below.   The commented out names are abstract class names.
42    // [DeclContext] indicates that the class also inherits from DeclContext.
43
44    // Decl
45         TranslationUnit,  // [DeclContext]
46    //   NamedDecl
47           Field,
48             CXXField,
49             ObjCIvar,
50             ObjCAtDefsField,
51           OverloadedFunction,
52           ObjCCategory,
53           ObjCCategoryImpl,
54           ObjCImplementation,
55           ObjCMethod,  // [DeclContext]
56           ObjCProtocol,
57           ObjCProperty,
58    //     ScopedDecl
59             Namespace,  // [DeclContext]
60    //       TypeDecl
61               Typedef,
62    //         TagDecl
63                 Enum,  // [DeclContext]
64                 Record,
65                   CXXRecord,  // [DeclContext]
66 	       TemplateTypeParm,
67    //       ValueDecl
68               EnumConstant,
69               Function,  // [DeclContext]
70                 CXXMethod,
71                   CXXConstructor,
72                   CXXDestructor,
73                   CXXConversion,
74               Var,
75                 ImplicitParam,
76                 CXXClassVar,
77                 ParmVar,
78  	         NonTypeTemplateParm,
79           ObjCInterface,  // [DeclContext]
80           ObjCCompatibleAlias,
81           ObjCClass,
82           ObjCForwardProtocol,
83           ObjCPropertyImpl,
84         LinkageSpec,
85         FileScopeAsm,
86	     Block, // [DeclContext]
87
88    // For each non-leaf class, we now define a mapping to the first/last member
89    // of the class, to allow efficient classof.
90    NamedFirst     = Field        , NamedLast     = NonTypeTemplateParm,
91    FieldFirst     = Field        , FieldLast     = ObjCAtDefsField,
92    ScopedFirst    = Namespace    , ScopedLast    = NonTypeTemplateParm,
93    TypeFirst      = Typedef      , TypeLast      = TemplateTypeParm,
94    TagFirst       = Enum         , TagLast       = CXXRecord,
95    RecordFirst    = Record       , RecordLast    = CXXRecord,
96    ValueFirst     = EnumConstant , ValueLast     = NonTypeTemplateParm,
97    FunctionFirst  = Function     , FunctionLast  = CXXConversion,
98    VarFirst       = Var          , VarLast       = NonTypeTemplateParm
99  };
100
101  /// IdentifierNamespace - According to C99 6.2.3, there are four namespaces,
102  /// labels, tags, members and ordinary identifiers. These are meant
103  /// as bitmasks, so that searches in C++ can look into the "tag" namespace
104  /// during ordinary lookup.
105  enum IdentifierNamespace {
106    IDNS_Label = 0x1,
107    IDNS_Tag = 0x2,
108    IDNS_Member = 0x4,
109    IDNS_Ordinary = 0x8
110  };
111
112  /// ObjCDeclQualifier - Qualifier used on types in method declarations
113  /// for remote messaging. They are meant for the arguments though and
114  /// applied to the Decls (ObjCMethodDecl and ParmVarDecl).
115  enum ObjCDeclQualifier {
116    OBJC_TQ_None = 0x0,
117    OBJC_TQ_In = 0x1,
118    OBJC_TQ_Inout = 0x2,
119    OBJC_TQ_Out = 0x4,
120    OBJC_TQ_Bycopy = 0x8,
121    OBJC_TQ_Byref = 0x10,
122    OBJC_TQ_Oneway = 0x20
123  };
124
125private:
126  /// Loc - The location that this decl.
127  SourceLocation Loc;
128
129  /// DeclKind - This indicates which class this is.
130  Kind DeclKind   :  8;
131
132  /// InvalidDecl - This indicates a semantic error occurred.
133  unsigned int InvalidDecl :  1;
134
135  /// HasAttrs - This indicates whether the decl has attributes or not.
136  unsigned int HasAttrs : 1;
137
138 protected:
139  /// Access - Used by C++ decls for the access specifier.
140  // NOTE: VC++ treats enums as signed, avoid using the AccessSpecifier enum
141  unsigned Access : 2;
142  friend class CXXClassMemberWrapper;
143
144  Decl(Kind DK, SourceLocation L) : Loc(L), DeclKind(DK), InvalidDecl(0),
145    HasAttrs(false) {
146    if (Decl::CollectingStats()) addDeclKind(DK);
147  }
148
149  virtual ~Decl();
150
151public:
152  SourceLocation getLocation() const { return Loc; }
153  void setLocation(SourceLocation L) { Loc = L; }
154
155  Kind getKind() const { return DeclKind; }
156  const char *getDeclKindName() const;
157
158  void addAttr(Attr *attr);
159  const Attr *getAttrs() const;
160  void swapAttrs(Decl *D);
161  void invalidateAttrs();
162
163  template<typename T> const T *getAttr() const {
164    for (const Attr *attr = getAttrs(); attr; attr = attr->getNext())
165      if (const T *V = dyn_cast<T>(attr))
166        return V;
167
168    return 0;
169  }
170
171  /// setInvalidDecl - Indicates the Decl had a semantic error. This
172  /// allows for graceful error recovery.
173  void setInvalidDecl() { InvalidDecl = 1; }
174  bool isInvalidDecl() const { return (bool) InvalidDecl; }
175
176  IdentifierNamespace getIdentifierNamespace() const {
177    switch (DeclKind) {
178    default: assert(0 && "Unknown decl kind!");
179    case ImplicitParam:
180    case Typedef:
181    case Function:
182    case Var:
183    case ParmVar:
184    case EnumConstant:
185    case NonTypeTemplateParm:
186    case ObjCInterface:
187    case ObjCCompatibleAlias:
188    case OverloadedFunction:
189    case CXXField:
190    case CXXMethod:
191    case CXXConversion:
192    case CXXClassVar:
193      return IDNS_Ordinary;
194    case Record:
195    case CXXRecord:
196    case TemplateTypeParm:
197    case Enum:
198      return IDNS_Tag;
199    case Namespace:
200      return IdentifierNamespace(IDNS_Tag | IDNS_Ordinary);
201    }
202  }
203
204  // getBody - If this Decl represents a declaration for a body of code,
205  //  such as a function or method definition, this method returns the top-level
206  //  Stmt* of that body.  Otherwise this method returns null.
207  virtual Stmt* getBody() const { return 0; }
208
209  // global temp stats (until we have a per-module visitor)
210  static void addDeclKind(Kind k);
211  static bool CollectingStats(bool Enable = false);
212  static void PrintStats();
213
214  // Implement isa/cast/dyncast/etc.
215  static bool classof(const Decl *) { return true; }
216  static DeclContext *castToDeclContext(const Decl *);
217  static Decl *castFromDeclContext(const DeclContext *);
218
219  /// Emit - Serialize this Decl to Bitcode.
220  void Emit(llvm::Serializer& S) const;
221
222  /// Create - Deserialize a Decl from Bitcode.
223  static Decl* Create(llvm::Deserializer& D, ASTContext& C);
224
225  /// Destroy - Call destructors and release memory.
226  virtual void Destroy(ASTContext& C);
227
228protected:
229  /// EmitImpl - Provides the subclass-specific serialization logic for
230  ///   serializing out a decl.
231  virtual void EmitImpl(llvm::Serializer& S) const {
232    // FIXME: This will eventually be a pure virtual function.
233    assert (false && "Not implemented.");
234  }
235
236  void EmitInRec(llvm::Serializer& S) const;
237  void ReadInRec(llvm::Deserializer& D, ASTContext& C);
238};
239
240/// DeclContext - This is used only as base class of specific decl types that
241/// can act as declaration contexts. These decls are:
242///
243///   TranslationUnitDecl
244///   NamespaceDecl
245///   FunctionDecl
246///   CXXRecordDecl
247///   EnumDecl
248///   ObjCMethodDecl
249///   ObjCInterfaceDecl
250///   BlockDecl
251///
252class DeclContext {
253  /// DeclKind - This indicates which class this is.
254  Decl::Kind DeclKind   :  8;
255
256  /// DeclChain - Linked list of declarations that are defined inside this
257  /// declaration context.
258  ScopedDecl *DeclChain;
259
260  // Used in the CastTo template to get the DeclKind
261  // from a Decl or a DeclContext. DeclContext doesn't have a getKind() method
262  // to avoid 'ambiguous access' compiler errors.
263  template<typename T> struct KindTrait {
264    static Decl::Kind getKind(const T *D) { return D->getKind(); }
265  };
266
267  // Used only by the ToDecl and FromDecl methods
268  template<typename To, typename From>
269  static To *CastTo(const From *D) {
270    Decl::Kind DK = KindTrait<From>::getKind(D);
271    switch(DK) {
272      case Decl::Block:
273        return static_cast<BlockDecl*>(const_cast<From*>(D));
274      case Decl::TranslationUnit:
275        return static_cast<TranslationUnitDecl*>(const_cast<From*>(D));
276      case Decl::Namespace:
277        return static_cast<NamespaceDecl*>(const_cast<From*>(D));
278      case Decl::Enum:
279        return static_cast<EnumDecl*>(const_cast<From*>(D));
280      case Decl::CXXRecord:
281        return static_cast<CXXRecordDecl*>(const_cast<From*>(D));
282      case Decl::ObjCMethod:
283        return static_cast<ObjCMethodDecl*>(const_cast<From*>(D));
284      case Decl::ObjCInterface:
285        return static_cast<ObjCInterfaceDecl*>(const_cast<From*>(D));
286      default:
287        if (DK >= Decl::FunctionFirst && DK <= Decl::FunctionLast)
288          return static_cast<FunctionDecl*>(const_cast<From*>(D));
289
290        assert(false && "a decl that inherits DeclContext isn't handled");
291        return 0;
292    }
293  }
294
295protected:
296  DeclContext(Decl::Kind K) : DeclKind(K), DeclChain(0) {}
297
298public:
299  /// getParent - Returns the containing DeclContext if this is a ScopedDecl,
300  /// else returns NULL.
301  const DeclContext *getParent() const;
302  DeclContext *getParent() {
303    return const_cast<DeclContext*>(
304                             const_cast<const DeclContext*>(this)->getParent());
305  }
306
307  /// getLexicalParent - Returns the containing lexical DeclContext. May be
308  /// different from getParent, e.g.:
309  ///
310  ///   namespace A {
311  ///      struct S;
312  ///   }
313  ///   struct A::S {}; // getParent() == namespace 'A'
314  ///                   // getLexicalParent() == translation unit
315  ///
316  const DeclContext *getLexicalParent() const;
317  DeclContext *getLexicalParent() {
318    return const_cast<DeclContext*>(
319                      const_cast<const DeclContext*>(this)->getLexicalParent());
320  }
321
322  bool isFunctionOrMethod() const {
323    switch (DeclKind) {
324      case Decl::Block:
325      case Decl::Function:
326      case Decl::CXXMethod:
327      case Decl::ObjCMethod:
328        return true;
329      default:
330        return false;
331    }
332  }
333
334  bool isFileContext() const {
335    return DeclKind == Decl::TranslationUnit || DeclKind == Decl::Namespace;
336  }
337
338  bool isCXXRecord() const {
339    return DeclKind == Decl::CXXRecord;
340  }
341
342  bool Encloses(DeclContext *DC) const {
343    for (; DC; DC = DC->getParent())
344      if (DC == this)
345        return true;
346    return false;
347  }
348
349  const ScopedDecl *getDeclChain() const { return DeclChain; }
350  ScopedDecl *getDeclChain() { return DeclChain; }
351  void setDeclChain(ScopedDecl *D) { DeclChain = D; }
352
353  static bool classof(const Decl *D) {
354    switch (D->getKind()) {
355      case Decl::TranslationUnit:
356      case Decl::Namespace:
357      case Decl::Enum:
358      case Decl::CXXRecord:
359      case Decl::ObjCMethod:
360      case Decl::ObjCInterface:
361      case Decl::Block:
362        return true;
363      default:
364        if (D->getKind() >= Decl::FunctionFirst &&
365            D->getKind() <= Decl::FunctionLast)
366          return true;
367        return false;
368    }
369  }
370  static bool classof(const DeclContext *D) { return true; }
371  static bool classof(const TranslationUnitDecl *D) { return true; }
372  static bool classof(const NamespaceDecl *D) { return true; }
373  static bool classof(const FunctionDecl *D) { return true; }
374  static bool classof(const CXXRecordDecl *D) { return true; }
375  static bool classof(const EnumDecl *D) { return true; }
376  static bool classof(const ObjCMethodDecl *D) { return true; }
377  static bool classof(const ObjCInterfaceDecl *D) { return true; }
378  static bool classof(const BlockDecl *D) { return true; }
379
380private:
381  void EmitOutRec(llvm::Serializer& S) const;
382  void ReadOutRec(llvm::Deserializer& D, ASTContext& C);
383
384  friend class Decl;
385};
386
387template<> struct DeclContext::KindTrait<DeclContext> {
388  static Decl::Kind getKind(const DeclContext *D) { return D->DeclKind; }
389};
390
391} // end clang.
392
393namespace llvm {
394
395/// Implement a isa_impl_wrap specialization to check whether a DeclContext is
396/// a specific Decl.
397template<class ToTy>
398struct isa_impl_wrap<ToTy,
399                     const ::clang::DeclContext,const ::clang::DeclContext> {
400  static bool doit(const ::clang::DeclContext &Val) {
401    return ToTy::classof(::clang::Decl::castFromDeclContext(&Val));
402  }
403};
404template<class ToTy>
405struct isa_impl_wrap<ToTy, ::clang::DeclContext, ::clang::DeclContext>
406  : public isa_impl_wrap<ToTy,
407                      const ::clang::DeclContext,const ::clang::DeclContext> {};
408
409/// Implement cast_convert_val for Decl -> DeclContext conversions.
410template<class FromTy>
411struct cast_convert_val< ::clang::DeclContext, FromTy, FromTy> {
412  static ::clang::DeclContext &doit(const FromTy &Val) {
413    return *FromTy::castToDeclContext(&Val);
414  }
415};
416
417template<class FromTy>
418struct cast_convert_val< ::clang::DeclContext, FromTy*, FromTy*> {
419  static ::clang::DeclContext *doit(const FromTy *Val) {
420    return FromTy::castToDeclContext(Val);
421  }
422};
423
424/// Implement cast_convert_val for DeclContext -> Decl conversions.
425template<class ToTy>
426struct cast_convert_val<ToTy,
427                        const ::clang::DeclContext,const ::clang::DeclContext> {
428  static ToTy &doit(const ::clang::DeclContext &Val) {
429    return *reinterpret_cast<ToTy*>(ToTy::castFromDeclContext(&Val));
430  }
431};
432template<class ToTy>
433struct cast_convert_val<ToTy, ::clang::DeclContext, ::clang::DeclContext>
434  : public cast_convert_val<ToTy,
435                      const ::clang::DeclContext,const ::clang::DeclContext> {};
436
437template<class ToTy>
438struct cast_convert_val<ToTy,
439                     const ::clang::DeclContext*, const ::clang::DeclContext*> {
440  static ToTy *doit(const ::clang::DeclContext *Val) {
441    return reinterpret_cast<ToTy*>(ToTy::castFromDeclContext(Val));
442  }
443};
444template<class ToTy>
445struct cast_convert_val<ToTy, ::clang::DeclContext*, ::clang::DeclContext*>
446  : public cast_convert_val<ToTy,
447                    const ::clang::DeclContext*,const ::clang::DeclContext*> {};
448
449} // end namespace llvm
450
451#endif
452