CIndexUSRs.cpp revision 97475834207bf5abb5b58534f783c9b71d4b9df1 
1//===- CIndexUSR.cpp - Clang-C Source Indexing Library --------------------===//
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 implements the generation and use of USRs from CXEntities.
11//
12//===----------------------------------------------------------------------===//
13
14#include "CIndexer.h"
15#include "CXCursor.h"
16#include "clang/AST/DeclTemplate.h"
17#include "clang/AST/DeclVisitor.h"
18#include "clang/Frontend/ASTUnit.h"
19#include "clang/Lex/PreprocessingRecord.h"
20#include "llvm/ADT/SmallString.h"
21#include "llvm/Support/raw_ostream.h"
22
23using namespace clang;
24using namespace clang::cxstring;
25
26//===----------------------------------------------------------------------===//
27// USR generation.
28//===----------------------------------------------------------------------===//
29
30namespace {
31class USRGenerator : public DeclVisitor<USRGenerator> {
32  llvm::SmallString<1024> Buf;
33  llvm::raw_svector_ostream Out;
34  bool IgnoreResults;
35  ASTUnit *AU;
36  bool generatedLoc;
37
38  llvm::DenseMap<const Type *, unsigned> TypeSubstitutions;
39
40public:
41  USRGenerator(const CXCursor *C = 0)
42    : Out(Buf),
43      IgnoreResults(false),
44      AU(C ? cxcursor::getCursorASTUnit(*C) : 0),
45      generatedLoc(false)
46  {
47    // Add the USR space prefix.
48    Out << "c:";
49  }
50
51  llvm::StringRef str() {
52    return Out.str();
53  }
54
55  USRGenerator* operator->() { return this; }
56
57  template <typename T>
58  llvm::raw_svector_ostream &operator<<(const T &x) {
59    Out << x;
60    return Out;
61  }
62
63  bool ignoreResults() const { return IgnoreResults; }
64
65  // Visitation methods from generating USRs from AST elements.
66  void VisitDeclContext(DeclContext *D);
67  void VisitFieldDecl(FieldDecl *D);
68  void VisitFunctionDecl(FunctionDecl *D);
69  void VisitNamedDecl(NamedDecl *D);
70  void VisitNamespaceDecl(NamespaceDecl *D);
71  void VisitNamespaceAliasDecl(NamespaceAliasDecl *D);
72  void VisitFunctionTemplateDecl(FunctionTemplateDecl *D);
73  void VisitClassTemplateDecl(ClassTemplateDecl *D);
74  void VisitObjCClassDecl(ObjCClassDecl *CD);
75  void VisitObjCContainerDecl(ObjCContainerDecl *CD);
76  void VisitObjCForwardProtocolDecl(ObjCForwardProtocolDecl *P);
77  void VisitObjCMethodDecl(ObjCMethodDecl *MD);
78  void VisitObjCPropertyDecl(ObjCPropertyDecl *D);
79  void VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D);
80  void VisitTagDecl(TagDecl *D);
81  void VisitTypedefDecl(TypedefDecl *D);
82  void VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D);
83  void VisitVarDecl(VarDecl *D);
84  void VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D);
85  void VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D);
86  void VisitLinkageSpecDecl(LinkageSpecDecl *D) {
87    IgnoreResults = true;
88  }
89  void VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
90    IgnoreResults = true;
91  }
92  void VisitUsingDecl(UsingDecl *D) {
93    IgnoreResults = true;
94  }
95  void VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
96    IgnoreResults = true;
97  }
98  void VisitUnresolvedUsingTypenameDecl(UnresolvedUsingTypenameDecl *D) {
99    IgnoreResults = true;
100  }
101
102  /// Generate the string component containing the location of the
103  ///  declaration.
104  bool GenLoc(const Decl *D);
105
106  /// String generation methods used both by the visitation methods
107  /// and from other clients that want to directly generate USRs.  These
108  /// methods do not construct complete USRs (which incorporate the parents
109  /// of an AST element), but only the fragments concerning the AST element
110  /// itself.
111
112  /// Generate a USR for an Objective-C class.
113  void GenObjCClass(llvm::StringRef cls);
114  /// Generate a USR for an Objective-C class category.
115  void GenObjCCategory(llvm::StringRef cls, llvm::StringRef cat);
116  /// Generate a USR fragment for an Objective-C instance variable.  The
117  /// complete USR can be created by concatenating the USR for the
118  /// encompassing class with this USR fragment.
119  void GenObjCIvar(llvm::StringRef ivar);
120  /// Generate a USR fragment for an Objective-C method.
121  void GenObjCMethod(llvm::StringRef sel, bool isInstanceMethod);
122  /// Generate a USR fragment for an Objective-C property.
123  void GenObjCProperty(llvm::StringRef prop);
124  /// Generate a USR for an Objective-C protocol.
125  void GenObjCProtocol(llvm::StringRef prot);
126
127  void VisitType(QualType T);
128  void VisitTemplateParameterList(const TemplateParameterList *Params);
129  void VisitTemplateName(TemplateName Name);
130  void VisitTemplateArgument(const TemplateArgument &Arg);
131
132  /// Emit a Decl's name using NamedDecl::printName() and return true if
133  ///  the decl had no name.
134  bool EmitDeclName(const NamedDecl *D);
135};
136
137} // end anonymous namespace
138
139//===----------------------------------------------------------------------===//
140// Generating USRs from ASTS.
141//===----------------------------------------------------------------------===//
142
143bool USRGenerator::EmitDeclName(const NamedDecl *D) {
144  Out.flush();
145  const unsigned startSize = Buf.size();
146  D->printName(Out);
147  Out.flush();
148  const unsigned endSize = Buf.size();
149  return startSize == endSize;
150}
151
152static bool InAnonymousNamespace(const Decl *D) {
153  if (const NamespaceDecl *ND = dyn_cast<NamespaceDecl>(D->getDeclContext()))
154    return ND->isAnonymousNamespace();
155  return false;
156}
157
158static inline bool ShouldGenerateLocation(const NamedDecl *D) {
159  return D->getLinkage() != ExternalLinkage && !InAnonymousNamespace(D);
160}
161
162void USRGenerator::VisitDeclContext(DeclContext *DC) {
163  if (NamedDecl *D = dyn_cast<NamedDecl>(DC))
164    Visit(D);
165}
166
167void USRGenerator::VisitFieldDecl(FieldDecl *D) {
168  VisitDeclContext(D->getDeclContext());
169  Out << (isa<ObjCIvarDecl>(D) ? "@" : "@FI@");
170  if (EmitDeclName(D)) {
171    // Bit fields can be anonymous.
172    IgnoreResults = true;
173    return;
174  }
175}
176
177void USRGenerator::VisitFunctionDecl(FunctionDecl *D) {
178  if (ShouldGenerateLocation(D) && GenLoc(D))
179    return;
180
181  VisitDeclContext(D->getDeclContext());
182  if (FunctionTemplateDecl *FunTmpl = D->getDescribedFunctionTemplate()) {
183    Out << "@FT@";
184    VisitTemplateParameterList(FunTmpl->getTemplateParameters());
185  } else
186    Out << "@F@";
187  D->printName(Out);
188
189  ASTContext &Ctx = AU->getASTContext();
190  if (!Ctx.getLangOptions().CPlusPlus || D->isExternC())
191    return;
192
193  // Mangle in type information for the arguments.
194  for (FunctionDecl::param_iterator I = D->param_begin(), E = D->param_end();
195       I != E; ++I) {
196    Out << '#';
197    if (ParmVarDecl *PD = *I)
198      VisitType(PD->getType());
199  }
200  if (D->isVariadic())
201    Out << '.';
202  Out << '#';
203  if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
204    if (MD->isStatic())
205      Out << 'S';
206    if (unsigned quals = MD->getTypeQualifiers())
207      Out << (char)('0' + quals);
208  }
209}
210
211void USRGenerator::VisitNamedDecl(NamedDecl *D) {
212  VisitDeclContext(D->getDeclContext());
213  Out << "@";
214
215  if (EmitDeclName(D)) {
216    // The string can be empty if the declaration has no name; e.g., it is
217    // the ParmDecl with no name for declaration of a function pointer type,
218    // e.g.: void  (*f)(void *);
219    // In this case, don't generate a USR.
220    IgnoreResults = true;
221  }
222}
223
224void USRGenerator::VisitVarDecl(VarDecl *D) {
225  // VarDecls can be declared 'extern' within a function or method body,
226  // but their enclosing DeclContext is the function, not the TU.  We need
227  // to check the storage class to correctly generate the USR.
228  if (ShouldGenerateLocation(D) && GenLoc(D))
229    return;
230
231  VisitDeclContext(D->getDeclContext());
232
233  // Variables always have simple names.
234  llvm::StringRef s = D->getName();
235
236  // The string can be empty if the declaration has no name; e.g., it is
237  // the ParmDecl with no name for declaration of a function pointer type, e.g.:
238  //    void  (*f)(void *);
239  // In this case, don't generate a USR.
240  if (s.empty())
241    IgnoreResults = true;
242  else
243    Out << '@' << s;
244}
245
246void USRGenerator::VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D) {
247  GenLoc(D);
248  return;
249}
250
251void USRGenerator::VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D) {
252  GenLoc(D);
253  return;
254}
255
256void USRGenerator::VisitNamespaceDecl(NamespaceDecl *D) {
257  if (D->isAnonymousNamespace()) {
258    Out << "@aN";
259    return;
260  }
261
262  VisitDeclContext(D->getDeclContext());
263  if (!IgnoreResults)
264    Out << "@N@" << D->getName();
265}
266
267void USRGenerator::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
268  VisitFunctionDecl(D->getTemplatedDecl());
269}
270
271void USRGenerator::VisitClassTemplateDecl(ClassTemplateDecl *D) {
272  VisitTagDecl(D->getTemplatedDecl());
273}
274
275void USRGenerator::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
276  VisitDeclContext(D->getDeclContext());
277  if (!IgnoreResults)
278    Out << "@NA@" << D->getName();
279}
280
281void USRGenerator::VisitObjCMethodDecl(ObjCMethodDecl *D) {
282  Decl *container = cast<Decl>(D->getDeclContext());
283
284  // The USR for a method declared in a class extension is based on
285  // the ObjCInterfaceDecl, not the ObjCCategoryDecl.
286  do {
287    if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(container))
288      if (CD->IsClassExtension()) {
289        // ID can be null with invalid code.
290        if (ObjCInterfaceDecl *ID = CD->getClassInterface()) {
291          Visit(ID);
292          break;
293        }
294        // Invalid code.  Can't generate USR.
295        IgnoreResults = true;
296        return;
297      }
298
299    Visit(container);
300  }
301  while (false);
302
303  // Ideally we would use 'GenObjCMethod', but this is such a hot path
304  // for Objective-C code that we don't want to use
305  // DeclarationName::getAsString().
306  Out << (D->isInstanceMethod() ? "(im)" : "(cm)");
307  DeclarationName N(D->getSelector());
308  N.printName(Out);
309}
310
311void USRGenerator::VisitObjCClassDecl(ObjCClassDecl *D) {
312  // FIXME: @class declarations can refer to multiple classes.  We need
313  //  to be able to traverse these.
314  IgnoreResults = true;
315}
316
317void USRGenerator::VisitObjCForwardProtocolDecl(ObjCForwardProtocolDecl *D) {
318  // FIXME: @protocol declarations can refer to multiple protocols.  We need
319  //  to be able to traverse these.
320  IgnoreResults = true;
321}
322
323void USRGenerator::VisitObjCContainerDecl(ObjCContainerDecl *D) {
324  switch (D->getKind()) {
325    default:
326      assert(false && "Invalid ObjC container.");
327    case Decl::ObjCInterface:
328    case Decl::ObjCImplementation:
329      GenObjCClass(D->getName());
330      break;
331    case Decl::ObjCCategory: {
332      ObjCCategoryDecl *CD = cast<ObjCCategoryDecl>(D);
333      ObjCInterfaceDecl *ID = CD->getClassInterface();
334      if (!ID) {
335        // Handle invalid code where the @interface might not
336        // have been specified.
337        // FIXME: We should be able to generate this USR even if the
338        // @interface isn't available.
339        IgnoreResults = true;
340        return;
341      }
342      // Specially handle class extensions, which are anonymous categories.
343      // We want to mangle in the location to uniquely distinguish them.
344      if (CD->IsClassExtension()) {
345        Out << "objc(ext)" << ID->getName() << '@';
346        GenLoc(CD);
347      }
348      else
349        GenObjCCategory(ID->getName(), CD->getName());
350
351      break;
352    }
353    case Decl::ObjCCategoryImpl: {
354      ObjCCategoryImplDecl *CD = cast<ObjCCategoryImplDecl>(D);
355      ObjCInterfaceDecl *ID = CD->getClassInterface();
356      if (!ID) {
357        // Handle invalid code where the @interface might not
358        // have been specified.
359        // FIXME: We should be able to generate this USR even if the
360        // @interface isn't available.
361        IgnoreResults = true;
362        return;
363      }
364      GenObjCCategory(ID->getName(), CD->getName());
365      break;
366    }
367    case Decl::ObjCProtocol:
368      GenObjCProtocol(cast<ObjCProtocolDecl>(D)->getName());
369      break;
370  }
371}
372
373void USRGenerator::VisitObjCPropertyDecl(ObjCPropertyDecl *D) {
374  Visit(cast<Decl>(D->getDeclContext()));
375  GenObjCProperty(D->getName());
376}
377
378void USRGenerator::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
379  if (ObjCPropertyDecl *PD = D->getPropertyDecl()) {
380    VisitObjCPropertyDecl(PD);
381    return;
382  }
383
384  IgnoreResults = true;
385}
386
387void USRGenerator::VisitTagDecl(TagDecl *D) {
388  // Add the location of the tag decl to handle resolution across
389  // translation units.
390  if (ShouldGenerateLocation(D) && GenLoc(D))
391    return;
392
393  D = D->getCanonicalDecl();
394  VisitDeclContext(D->getDeclContext());
395
396  bool AlreadyStarted = false;
397  if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(D)) {
398    if (ClassTemplateDecl *ClassTmpl = CXXRecord->getDescribedClassTemplate()) {
399      AlreadyStarted = true;
400
401      switch (D->getTagKind()) {
402      case TTK_Struct: Out << "@ST"; break;
403      case TTK_Class:  Out << "@CT"; break;
404      case TTK_Union:  Out << "@UT"; break;
405      case TTK_Enum: llvm_unreachable("enum template"); break;
406      }
407      VisitTemplateParameterList(ClassTmpl->getTemplateParameters());
408    } else if (ClassTemplatePartialSpecializationDecl *PartialSpec
409                = dyn_cast<ClassTemplatePartialSpecializationDecl>(CXXRecord)) {
410      AlreadyStarted = true;
411
412      switch (D->getTagKind()) {
413      case TTK_Struct: Out << "@SP"; break;
414      case TTK_Class:  Out << "@CP"; break;
415      case TTK_Union:  Out << "@UP"; break;
416      case TTK_Enum: llvm_unreachable("enum partial specialization"); break;
417      }
418      VisitTemplateParameterList(PartialSpec->getTemplateParameters());
419    }
420  }
421
422  if (!AlreadyStarted) {
423    switch (D->getTagKind()) {
424      case TTK_Struct: Out << "@S"; break;
425      case TTK_Class:  Out << "@C"; break;
426      case TTK_Union:  Out << "@U"; break;
427      case TTK_Enum:   Out << "@E"; break;
428    }
429  }
430
431  Out << '@';
432  Out.flush();
433  assert(Buf.size() > 0);
434  const unsigned off = Buf.size() - 1;
435
436  if (EmitDeclName(D)) {
437    if (const TypedefDecl *TD = D->getTypedefForAnonDecl()) {
438      Buf[off] = 'A';
439      Out << '@' << TD;
440    }
441    else
442      Buf[off] = 'a';
443  }
444
445  // For a class template specialization, mangle the template arguments.
446  if (ClassTemplateSpecializationDecl *Spec
447                              = dyn_cast<ClassTemplateSpecializationDecl>(D)) {
448    const TemplateArgumentList &Args = Spec->getTemplateInstantiationArgs();
449    Out << '>';
450    for (unsigned I = 0, N = Args.size(); I != N; ++I) {
451      Out << '#';
452      VisitTemplateArgument(Args.get(I));
453    }
454  }
455}
456
457void USRGenerator::VisitTypedefDecl(TypedefDecl *D) {
458  if (ShouldGenerateLocation(D) && GenLoc(D))
459    return;
460  DeclContext *DC = D->getDeclContext();
461  if (NamedDecl *DCN = dyn_cast<NamedDecl>(DC))
462    Visit(DCN);
463  Out << "@T@";
464  Out << D->getName();
465}
466
467void USRGenerator::VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D) {
468  GenLoc(D);
469  return;
470}
471
472bool USRGenerator::GenLoc(const Decl *D) {
473  if (generatedLoc)
474    return IgnoreResults;
475  generatedLoc = true;
476
477  const SourceManager &SM = AU->getSourceManager();
478  SourceLocation L = D->getLocStart();
479  if (L.isInvalid()) {
480    IgnoreResults = true;
481    return true;
482  }
483  L = SM.getInstantiationLoc(L);
484  const std::pair<FileID, unsigned> &Decomposed = SM.getDecomposedLoc(L);
485  const FileEntry *FE = SM.getFileEntryForID(Decomposed.first);
486  if (FE) {
487    llvm::sys::Path P(FE->getName());
488    Out << P.getLast();
489  }
490  else {
491    // This case really isn't interesting.
492    IgnoreResults = true;
493    return true;
494  }
495  // Use the offest into the FileID to represent the location.  Using
496  // a line/column can cause us to look back at the original source file,
497  // which is expensive.
498  Out << '@' << Decomposed.second;
499  return IgnoreResults;
500}
501
502void USRGenerator::VisitType(QualType T) {
503  // This method mangles in USR information for types.  It can possibly
504  // just reuse the naming-mangling logic used by codegen, although the
505  // requirements for USRs might not be the same.
506  ASTContext &Ctx = AU->getASTContext();
507
508  do {
509    T = Ctx.getCanonicalType(T);
510    Qualifiers Q = T.getQualifiers();
511    unsigned qVal = 0;
512    if (Q.hasConst())
513      qVal |= 0x1;
514    if (Q.hasVolatile())
515      qVal |= 0x2;
516    if (Q.hasRestrict())
517      qVal |= 0x4;
518    if(qVal)
519      Out << ((char) ('0' + qVal));
520
521    // Mangle in ObjC GC qualifiers?
522
523    if (const BuiltinType *BT = T->getAs<BuiltinType>()) {
524      unsigned char c = '\0';
525      switch (BT->getKind()) {
526        case BuiltinType::Void:
527          c = 'v'; break;
528        case BuiltinType::Bool:
529          c = 'b'; break;
530        case BuiltinType::Char_U:
531        case BuiltinType::UChar:
532          c = 'c'; break;
533        case BuiltinType::Char16:
534          c = 'q'; break;
535        case BuiltinType::Char32:
536          c = 'w'; break;
537        case BuiltinType::UShort:
538          c = 's'; break;
539        case BuiltinType::UInt:
540          c = 'i'; break;
541        case BuiltinType::ULong:
542          c = 'l'; break;
543        case BuiltinType::ULongLong:
544          c = 'k'; break;
545        case BuiltinType::UInt128:
546          c = 'j'; break;
547        case BuiltinType::Char_S:
548        case BuiltinType::SChar:
549          c = 'C'; break;
550        case BuiltinType::WChar:
551          c = 'W'; break;
552        case BuiltinType::Short:
553          c = 'S'; break;
554        case BuiltinType::Int:
555          c = 'I'; break;
556        case BuiltinType::Long:
557          c = 'L'; break;
558        case BuiltinType::LongLong:
559          c = 'K'; break;
560        case BuiltinType::Int128:
561          c = 'J'; break;
562        case BuiltinType::Float:
563          c = 'f'; break;
564        case BuiltinType::Double:
565          c = 'd'; break;
566        case BuiltinType::LongDouble:
567          c = 'D'; break;
568        case BuiltinType::NullPtr:
569          c = 'n'; break;
570        case BuiltinType::Overload:
571        case BuiltinType::Dependent:
572        case BuiltinType::UndeducedAuto:
573          IgnoreResults = true;
574          return;
575        case BuiltinType::ObjCId:
576          c = 'o'; break;
577        case BuiltinType::ObjCClass:
578          c = 'O'; break;
579        case BuiltinType::ObjCSel:
580          c = 'e'; break;
581      }
582      Out << c;
583      return;
584    }
585
586    // If we have already seen this (non-built-in) type, use a substitution
587    // encoding.
588    llvm::DenseMap<const Type *, unsigned>::iterator Substitution
589      = TypeSubstitutions.find(T.getTypePtr());
590    if (Substitution != TypeSubstitutions.end()) {
591      Out << 'S' << Substitution->second << '_';
592      return;
593    } else {
594      // Record this as a substitution.
595      unsigned Number = TypeSubstitutions.size();
596      TypeSubstitutions[T.getTypePtr()] = Number;
597    }
598
599    if (const PointerType *PT = T->getAs<PointerType>()) {
600      Out << '*';
601      T = PT->getPointeeType();
602      continue;
603    }
604    if (const ReferenceType *RT = T->getAs<ReferenceType>()) {
605      Out << '&';
606      T = RT->getPointeeType();
607      continue;
608    }
609    if (const FunctionProtoType *FT = T->getAs<FunctionProtoType>()) {
610      Out << 'F';
611      VisitType(FT->getResultType());
612      for (FunctionProtoType::arg_type_iterator
613            I = FT->arg_type_begin(), E = FT->arg_type_end(); I!=E; ++I) {
614        VisitType(*I);
615      }
616      if (FT->isVariadic())
617        Out << '.';
618      return;
619    }
620    if (const BlockPointerType *BT = T->getAs<BlockPointerType>()) {
621      Out << 'B';
622      T = BT->getPointeeType();
623      continue;
624    }
625    if (const ComplexType *CT = T->getAs<ComplexType>()) {
626      Out << '<';
627      T = CT->getElementType();
628      continue;
629    }
630    if (const TagType *TT = T->getAs<TagType>()) {
631      Out << '$';
632      VisitTagDecl(TT->getDecl());
633      return;
634    }
635    if (const TemplateTypeParmType *TTP = T->getAs<TemplateTypeParmType>()) {
636      Out << 't' << TTP->getDepth() << '.' << TTP->getIndex();
637      return;
638    }
639    if (const TemplateSpecializationType *Spec
640                                    = T->getAs<TemplateSpecializationType>()) {
641      Out << '>';
642      VisitTemplateName(Spec->getTemplateName());
643      Out << Spec->getNumArgs();
644      for (unsigned I = 0, N = Spec->getNumArgs(); I != N; ++I)
645        VisitTemplateArgument(Spec->getArg(I));
646      return;
647    }
648
649    // Unhandled type.
650    Out << ' ';
651    break;
652  } while (true);
653}
654
655void USRGenerator::VisitTemplateParameterList(
656                                         const TemplateParameterList *Params) {
657  if (!Params)
658    return;
659  Out << '>' << Params->size();
660  for (TemplateParameterList::const_iterator P = Params->begin(),
661                                          PEnd = Params->end();
662       P != PEnd; ++P) {
663    Out << '#';
664    if (isa<TemplateTypeParmDecl>(*P)) {
665      Out << 'T';
666      continue;
667    }
668
669    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
670      Out << 'N';
671      VisitType(NTTP->getType());
672      continue;
673    }
674
675    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
676    Out << 't';
677    VisitTemplateParameterList(TTP->getTemplateParameters());
678  }
679}
680
681void USRGenerator::VisitTemplateName(TemplateName Name) {
682  if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
683    if (TemplateTemplateParmDecl *TTP
684                              = dyn_cast<TemplateTemplateParmDecl>(Template)) {
685      Out << 't' << TTP->getDepth() << '.' << TTP->getIndex();
686      return;
687    }
688
689    Visit(Template);
690    return;
691  }
692
693  // FIXME: Visit dependent template names.
694}
695
696void USRGenerator::VisitTemplateArgument(const TemplateArgument &Arg) {
697  switch (Arg.getKind()) {
698  case TemplateArgument::Null:
699    break;
700
701  case TemplateArgument::Declaration:
702    if (Decl *D = Arg.getAsDecl())
703      Visit(D);
704    break;
705
706  case TemplateArgument::Template:
707    VisitTemplateName(Arg.getAsTemplate());
708    break;
709
710  case TemplateArgument::Expression:
711    // FIXME: Visit expressions.
712    break;
713
714  case TemplateArgument::Pack:
715    // FIXME: Variadic templates
716    break;
717
718  case TemplateArgument::Type:
719    VisitType(Arg.getAsType());
720    break;
721
722  case TemplateArgument::Integral:
723    Out << 'V';
724    VisitType(Arg.getIntegralType());
725    Out << *Arg.getAsIntegral();
726    break;
727  }
728}
729
730//===----------------------------------------------------------------------===//
731// General purpose USR generation methods.
732//===----------------------------------------------------------------------===//
733
734void USRGenerator::GenObjCClass(llvm::StringRef cls) {
735  Out << "objc(cs)" << cls;
736}
737
738void USRGenerator::GenObjCCategory(llvm::StringRef cls, llvm::StringRef cat) {
739  Out << "objc(cy)" << cls << '@' << cat;
740}
741
742void USRGenerator::GenObjCIvar(llvm::StringRef ivar) {
743  Out << '@' << ivar;
744}
745
746void USRGenerator::GenObjCMethod(llvm::StringRef meth, bool isInstanceMethod) {
747  Out << (isInstanceMethod ? "(im)" : "(cm)") << meth;
748}
749
750void USRGenerator::GenObjCProperty(llvm::StringRef prop) {
751  Out << "(py)" << prop;
752}
753
754void USRGenerator::GenObjCProtocol(llvm::StringRef prot) {
755  Out << "objc(pl)" << prot;
756}
757
758//===----------------------------------------------------------------------===//
759// API hooks.
760//===----------------------------------------------------------------------===//
761
762static inline llvm::StringRef extractUSRSuffix(llvm::StringRef s) {
763  return s.startswith("c:") ? s.substr(2) : "";
764}
765
766static CXString getDeclCursorUSR(const CXCursor &C) {
767  Decl *D = cxcursor::getCursorDecl(C);
768
769  // Don't generate USRs for things with invalid locations.
770  if (!D || D->getLocStart().isInvalid())
771    return createCXString("");
772
773  // Check if the cursor has 'NoLinkage'.
774  if (const NamedDecl *ND = dyn_cast<NamedDecl>(D))
775    switch (ND->getLinkage()) {
776      case ExternalLinkage:
777        // Generate USRs for all entities with external linkage.
778        break;
779      case NoLinkage:
780      case UniqueExternalLinkage:
781        // We allow enums, typedefs, and structs that have no linkage to
782        // have USRs that are anchored to the file they were defined in
783        // (e.g., the header).  This is a little gross, but in principal
784        // enums/anonymous structs/etc. defined in a common header file
785        // are referred to across multiple translation units.
786        if (isa<TagDecl>(ND) || isa<TypedefDecl>(ND) ||
787            isa<EnumConstantDecl>(ND) || isa<FieldDecl>(ND) ||
788            isa<VarDecl>(ND) || isa<NamespaceDecl>(ND))
789          break;
790        // Fall-through.
791      case InternalLinkage:
792        if (isa<FunctionDecl>(ND))
793          break;
794    }
795
796  USRGenerator UG(&C);
797  UG->Visit(D);
798
799  if (UG->ignoreResults())
800    return createCXString("");
801
802#if 0
803  // For development testing.
804  assert(UG.str().size() > 2);
805#endif
806
807    // Return a copy of the string that must be disposed by the caller.
808  return createCXString(UG.str(), true);
809}
810
811extern "C" {
812
813CXString clang_getCursorUSR(CXCursor C) {
814  const CXCursorKind &K = clang_getCursorKind(C);
815
816  if (clang_isDeclaration(K))
817      return getDeclCursorUSR(C);
818
819  if (K == CXCursor_MacroDefinition) {
820    USRGenerator UG(&C);
821    UG << "macro@"
822       << cxcursor::getCursorMacroDefinition(C)->getName()->getNameStart();
823    return createCXString(UG.str(), true);
824  }
825
826  return createCXString("");
827}
828
829CXString clang_constructUSR_ObjCIvar(const char *name, CXString classUSR) {
830  USRGenerator UG;
831  UG << extractUSRSuffix(clang_getCString(classUSR));
832  UG->GenObjCIvar(name);
833  return createCXString(UG.str(), true);
834}
835
836CXString clang_constructUSR_ObjCMethod(const char *name,
837                                       unsigned isInstanceMethod,
838                                       CXString classUSR) {
839  USRGenerator UG;
840  UG << extractUSRSuffix(clang_getCString(classUSR));
841  UG->GenObjCMethod(name, isInstanceMethod);
842  return createCXString(UG.str(), true);
843}
844
845CXString clang_constructUSR_ObjCClass(const char *name) {
846  USRGenerator UG;
847  UG->GenObjCClass(name);
848  return createCXString(UG.str(), true);
849}
850
851CXString clang_constructUSR_ObjCProtocol(const char *name) {
852  USRGenerator UG;
853  UG->GenObjCProtocol(name);
854  return createCXString(UG.str(), true);
855}
856
857CXString clang_constructUSR_ObjCCategory(const char *class_name,
858                                         const char *category_name) {
859  USRGenerator UG;
860  UG->GenObjCCategory(class_name, category_name);
861  return createCXString(UG.str(), true);
862}
863
864CXString clang_constructUSR_ObjCProperty(const char *property,
865                                         CXString classUSR) {
866  USRGenerator UG;
867  UG << extractUSRSuffix(clang_getCString(classUSR));
868  UG->GenObjCProperty(property);
869  return createCXString(UG.str(), true);
870}
871
872} // end extern "C"
873