1//===- USRGeneration.cpp - Routines for USR generation --------------------===//
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#include "clang/Index/USRGeneration.h"
11#include "clang/AST/ASTContext.h"
12#include "clang/AST/DeclTemplate.h"
13#include "clang/AST/DeclVisitor.h"
14#include "clang/Lex/PreprocessingRecord.h"
15#include "llvm/ADT/SmallString.h"
16#include "llvm/Support/Path.h"
17#include "llvm/Support/raw_ostream.h"
18
19using namespace clang;
20using namespace clang::index;
21
22//===----------------------------------------------------------------------===//
23// USR generation.
24//===----------------------------------------------------------------------===//
25
26/// \returns true on error.
27static bool printLoc(llvm::raw_ostream &OS, SourceLocation Loc,
28                     const SourceManager &SM, bool IncludeOffset) {
29  if (Loc.isInvalid()) {
30    return true;
31  }
32  Loc = SM.getExpansionLoc(Loc);
33  const std::pair<FileID, unsigned> &Decomposed = SM.getDecomposedLoc(Loc);
34  const FileEntry *FE = SM.getFileEntryForID(Decomposed.first);
35  if (FE) {
36    OS << llvm::sys::path::filename(FE->getName());
37  } else {
38    // This case really isn't interesting.
39    return true;
40  }
41  if (IncludeOffset) {
42    // Use the offest into the FileID to represent the location.  Using
43    // a line/column can cause us to look back at the original source file,
44    // which is expensive.
45    OS << '@' << Decomposed.second;
46  }
47  return false;
48}
49
50namespace {
51class USRGenerator : public ConstDeclVisitor<USRGenerator> {
52  SmallVectorImpl<char> &Buf;
53  llvm::raw_svector_ostream Out;
54  bool IgnoreResults;
55  ASTContext *Context;
56  bool generatedLoc;
57
58  llvm::DenseMap<const Type *, unsigned> TypeSubstitutions;
59
60public:
61  explicit USRGenerator(ASTContext *Ctx, SmallVectorImpl<char> &Buf)
62  : Buf(Buf),
63    Out(Buf),
64    IgnoreResults(false),
65    Context(Ctx),
66    generatedLoc(false)
67  {
68    // Add the USR space prefix.
69    Out << getUSRSpacePrefix();
70  }
71
72  bool ignoreResults() const { return IgnoreResults; }
73
74  // Visitation methods from generating USRs from AST elements.
75  void VisitDeclContext(const DeclContext *D);
76  void VisitFieldDecl(const FieldDecl *D);
77  void VisitFunctionDecl(const FunctionDecl *D);
78  void VisitNamedDecl(const NamedDecl *D);
79  void VisitNamespaceDecl(const NamespaceDecl *D);
80  void VisitNamespaceAliasDecl(const NamespaceAliasDecl *D);
81  void VisitFunctionTemplateDecl(const FunctionTemplateDecl *D);
82  void VisitClassTemplateDecl(const ClassTemplateDecl *D);
83  void VisitObjCContainerDecl(const ObjCContainerDecl *CD);
84  void VisitObjCMethodDecl(const ObjCMethodDecl *MD);
85  void VisitObjCPropertyDecl(const ObjCPropertyDecl *D);
86  void VisitObjCPropertyImplDecl(const ObjCPropertyImplDecl *D);
87  void VisitTagDecl(const TagDecl *D);
88  void VisitTypedefDecl(const TypedefDecl *D);
89  void VisitTemplateTypeParmDecl(const TemplateTypeParmDecl *D);
90  void VisitVarDecl(const VarDecl *D);
91  void VisitNonTypeTemplateParmDecl(const NonTypeTemplateParmDecl *D);
92  void VisitTemplateTemplateParmDecl(const TemplateTemplateParmDecl *D);
93  void VisitLinkageSpecDecl(const LinkageSpecDecl *D) {
94    IgnoreResults = true;
95  }
96  void VisitUsingDirectiveDecl(const UsingDirectiveDecl *D) {
97    IgnoreResults = true;
98  }
99  void VisitUsingDecl(const UsingDecl *D) {
100    IgnoreResults = true;
101  }
102  void VisitUnresolvedUsingValueDecl(const UnresolvedUsingValueDecl *D) {
103    IgnoreResults = true;
104  }
105  void VisitUnresolvedUsingTypenameDecl(const UnresolvedUsingTypenameDecl *D) {
106    IgnoreResults = true;
107  }
108
109  bool ShouldGenerateLocation(const NamedDecl *D);
110
111  bool isLocal(const NamedDecl *D) {
112    return D->getParentFunctionOrMethod() != nullptr;
113  }
114
115  /// Generate the string component containing the location of the
116  ///  declaration.
117  bool GenLoc(const Decl *D, bool IncludeOffset);
118
119  /// String generation methods used both by the visitation methods
120  /// and from other clients that want to directly generate USRs.  These
121  /// methods do not construct complete USRs (which incorporate the parents
122  /// of an AST element), but only the fragments concerning the AST element
123  /// itself.
124
125  /// Generate a USR for an Objective-C class.
126  void GenObjCClass(StringRef cls) {
127    generateUSRForObjCClass(cls, Out);
128  }
129  /// Generate a USR for an Objective-C class category.
130  void GenObjCCategory(StringRef cls, StringRef cat) {
131    generateUSRForObjCCategory(cls, cat, Out);
132  }
133  /// Generate a USR fragment for an Objective-C property.
134  void GenObjCProperty(StringRef prop) {
135    generateUSRForObjCProperty(prop, Out);
136  }
137  /// Generate a USR for an Objective-C protocol.
138  void GenObjCProtocol(StringRef prot) {
139    generateUSRForObjCProtocol(prot, Out);
140  }
141
142  void VisitType(QualType T);
143  void VisitTemplateParameterList(const TemplateParameterList *Params);
144  void VisitTemplateName(TemplateName Name);
145  void VisitTemplateArgument(const TemplateArgument &Arg);
146
147  /// Emit a Decl's name using NamedDecl::printName() and return true if
148  ///  the decl had no name.
149  bool EmitDeclName(const NamedDecl *D);
150};
151
152} // end anonymous namespace
153
154//===----------------------------------------------------------------------===//
155// Generating USRs from ASTS.
156//===----------------------------------------------------------------------===//
157
158bool USRGenerator::EmitDeclName(const NamedDecl *D) {
159  Out.flush();
160  const unsigned startSize = Buf.size();
161  D->printName(Out);
162  Out.flush();
163  const unsigned endSize = Buf.size();
164  return startSize == endSize;
165}
166
167bool USRGenerator::ShouldGenerateLocation(const NamedDecl *D) {
168  if (D->isExternallyVisible())
169    return false;
170  if (D->getParentFunctionOrMethod())
171    return true;
172  const SourceManager &SM = Context->getSourceManager();
173  return !SM.isInSystemHeader(D->getLocation());
174}
175
176void USRGenerator::VisitDeclContext(const DeclContext *DC) {
177  if (const NamedDecl *D = dyn_cast<NamedDecl>(DC))
178    Visit(D);
179}
180
181void USRGenerator::VisitFieldDecl(const FieldDecl *D) {
182  // The USR for an ivar declared in a class extension is based on the
183  // ObjCInterfaceDecl, not the ObjCCategoryDecl.
184  if (const ObjCInterfaceDecl *ID = Context->getObjContainingInterface(D))
185    Visit(ID);
186  else
187    VisitDeclContext(D->getDeclContext());
188  Out << (isa<ObjCIvarDecl>(D) ? "@" : "@FI@");
189  if (EmitDeclName(D)) {
190    // Bit fields can be anonymous.
191    IgnoreResults = true;
192    return;
193  }
194}
195
196void USRGenerator::VisitFunctionDecl(const FunctionDecl *D) {
197  if (ShouldGenerateLocation(D) && GenLoc(D, /*IncludeOffset=*/isLocal(D)))
198    return;
199
200  VisitDeclContext(D->getDeclContext());
201  bool IsTemplate = false;
202  if (FunctionTemplateDecl *FunTmpl = D->getDescribedFunctionTemplate()) {
203    IsTemplate = true;
204    Out << "@FT@";
205    VisitTemplateParameterList(FunTmpl->getTemplateParameters());
206  } else
207    Out << "@F@";
208  D->printName(Out);
209
210  ASTContext &Ctx = *Context;
211  if (!Ctx.getLangOpts().CPlusPlus || D->isExternC())
212    return;
213
214  if (const TemplateArgumentList *
215        SpecArgs = D->getTemplateSpecializationArgs()) {
216    Out << '<';
217    for (unsigned I = 0, N = SpecArgs->size(); I != N; ++I) {
218      Out << '#';
219      VisitTemplateArgument(SpecArgs->get(I));
220    }
221    Out << '>';
222  }
223
224  // Mangle in type information for the arguments.
225  for (auto PD : D->params()) {
226    Out << '#';
227    VisitType(PD->getType());
228  }
229  if (D->isVariadic())
230    Out << '.';
231  if (IsTemplate) {
232    // Function templates can be overloaded by return type, for example:
233    // \code
234    //   template <class T> typename T::A foo() {}
235    //   template <class T> typename T::B foo() {}
236    // \endcode
237    Out << '#';
238    VisitType(D->getReturnType());
239  }
240  Out << '#';
241  if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
242    if (MD->isStatic())
243      Out << 'S';
244    if (unsigned quals = MD->getTypeQualifiers())
245      Out << (char)('0' + quals);
246    switch (MD->getRefQualifier()) {
247    case RQ_None: break;
248    case RQ_LValue: Out << '&'; break;
249    case RQ_RValue: Out << "&&"; break;
250    }
251  }
252}
253
254void USRGenerator::VisitNamedDecl(const NamedDecl *D) {
255  VisitDeclContext(D->getDeclContext());
256  Out << "@";
257
258  if (EmitDeclName(D)) {
259    // The string can be empty if the declaration has no name; e.g., it is
260    // the ParmDecl with no name for declaration of a function pointer type,
261    // e.g.: void  (*f)(void *);
262    // In this case, don't generate a USR.
263    IgnoreResults = true;
264  }
265}
266
267void USRGenerator::VisitVarDecl(const VarDecl *D) {
268  // VarDecls can be declared 'extern' within a function or method body,
269  // but their enclosing DeclContext is the function, not the TU.  We need
270  // to check the storage class to correctly generate the USR.
271  if (ShouldGenerateLocation(D) && GenLoc(D, /*IncludeOffset=*/isLocal(D)))
272    return;
273
274  VisitDeclContext(D->getDeclContext());
275
276  // Variables always have simple names.
277  StringRef s = D->getName();
278
279  // The string can be empty if the declaration has no name; e.g., it is
280  // the ParmDecl with no name for declaration of a function pointer type, e.g.:
281  //    void  (*f)(void *);
282  // In this case, don't generate a USR.
283  if (s.empty())
284    IgnoreResults = true;
285  else
286    Out << '@' << s;
287}
288
289void USRGenerator::VisitNonTypeTemplateParmDecl(
290                                        const NonTypeTemplateParmDecl *D) {
291  GenLoc(D, /*IncludeOffset=*/true);
292  return;
293}
294
295void USRGenerator::VisitTemplateTemplateParmDecl(
296                                        const TemplateTemplateParmDecl *D) {
297  GenLoc(D, /*IncludeOffset=*/true);
298  return;
299}
300
301void USRGenerator::VisitNamespaceDecl(const NamespaceDecl *D) {
302  if (D->isAnonymousNamespace()) {
303    Out << "@aN";
304    return;
305  }
306
307  VisitDeclContext(D->getDeclContext());
308  if (!IgnoreResults)
309    Out << "@N@" << D->getName();
310}
311
312void USRGenerator::VisitFunctionTemplateDecl(const FunctionTemplateDecl *D) {
313  VisitFunctionDecl(D->getTemplatedDecl());
314}
315
316void USRGenerator::VisitClassTemplateDecl(const ClassTemplateDecl *D) {
317  VisitTagDecl(D->getTemplatedDecl());
318}
319
320void USRGenerator::VisitNamespaceAliasDecl(const NamespaceAliasDecl *D) {
321  VisitDeclContext(D->getDeclContext());
322  if (!IgnoreResults)
323    Out << "@NA@" << D->getName();
324}
325
326void USRGenerator::VisitObjCMethodDecl(const ObjCMethodDecl *D) {
327  const DeclContext *container = D->getDeclContext();
328  if (const ObjCProtocolDecl *pd = dyn_cast<ObjCProtocolDecl>(container)) {
329    Visit(pd);
330  }
331  else {
332    // The USR for a method declared in a class extension or category is based on
333    // the ObjCInterfaceDecl, not the ObjCCategoryDecl.
334    const ObjCInterfaceDecl *ID = D->getClassInterface();
335    if (!ID) {
336      IgnoreResults = true;
337      return;
338    }
339    Visit(ID);
340  }
341  // Ideally we would use 'GenObjCMethod', but this is such a hot path
342  // for Objective-C code that we don't want to use
343  // DeclarationName::getAsString().
344  Out << (D->isInstanceMethod() ? "(im)" : "(cm)")
345      << DeclarationName(D->getSelector());
346}
347
348void USRGenerator::VisitObjCContainerDecl(const ObjCContainerDecl *D) {
349  switch (D->getKind()) {
350    default:
351      llvm_unreachable("Invalid ObjC container.");
352    case Decl::ObjCInterface:
353    case Decl::ObjCImplementation:
354      GenObjCClass(D->getName());
355      break;
356    case Decl::ObjCCategory: {
357      const ObjCCategoryDecl *CD = cast<ObjCCategoryDecl>(D);
358      const ObjCInterfaceDecl *ID = CD->getClassInterface();
359      if (!ID) {
360        // Handle invalid code where the @interface might not
361        // have been specified.
362        // FIXME: We should be able to generate this USR even if the
363        // @interface isn't available.
364        IgnoreResults = true;
365        return;
366      }
367      // Specially handle class extensions, which are anonymous categories.
368      // We want to mangle in the location to uniquely distinguish them.
369      if (CD->IsClassExtension()) {
370        Out << "objc(ext)" << ID->getName() << '@';
371        GenLoc(CD, /*IncludeOffset=*/true);
372      }
373      else
374        GenObjCCategory(ID->getName(), CD->getName());
375
376      break;
377    }
378    case Decl::ObjCCategoryImpl: {
379      const ObjCCategoryImplDecl *CD = cast<ObjCCategoryImplDecl>(D);
380      const ObjCInterfaceDecl *ID = CD->getClassInterface();
381      if (!ID) {
382        // Handle invalid code where the @interface might not
383        // have been specified.
384        // FIXME: We should be able to generate this USR even if the
385        // @interface isn't available.
386        IgnoreResults = true;
387        return;
388      }
389      GenObjCCategory(ID->getName(), CD->getName());
390      break;
391    }
392    case Decl::ObjCProtocol:
393      GenObjCProtocol(cast<ObjCProtocolDecl>(D)->getName());
394      break;
395  }
396}
397
398void USRGenerator::VisitObjCPropertyDecl(const ObjCPropertyDecl *D) {
399  // The USR for a property declared in a class extension or category is based
400  // on the ObjCInterfaceDecl, not the ObjCCategoryDecl.
401  if (const ObjCInterfaceDecl *ID = Context->getObjContainingInterface(D))
402    Visit(ID);
403  else
404    Visit(cast<Decl>(D->getDeclContext()));
405  GenObjCProperty(D->getName());
406}
407
408void USRGenerator::VisitObjCPropertyImplDecl(const ObjCPropertyImplDecl *D) {
409  if (ObjCPropertyDecl *PD = D->getPropertyDecl()) {
410    VisitObjCPropertyDecl(PD);
411    return;
412  }
413
414  IgnoreResults = true;
415}
416
417void USRGenerator::VisitTagDecl(const TagDecl *D) {
418  // Add the location of the tag decl to handle resolution across
419  // translation units.
420  if (ShouldGenerateLocation(D) && GenLoc(D, /*IncludeOffset=*/isLocal(D)))
421    return;
422
423  D = D->getCanonicalDecl();
424  VisitDeclContext(D->getDeclContext());
425
426  bool AlreadyStarted = false;
427  if (const CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(D)) {
428    if (ClassTemplateDecl *ClassTmpl = CXXRecord->getDescribedClassTemplate()) {
429      AlreadyStarted = true;
430
431      switch (D->getTagKind()) {
432      case TTK_Interface:
433      case TTK_Class:
434      case TTK_Struct: Out << "@ST"; break;
435      case TTK_Union:  Out << "@UT"; break;
436      case TTK_Enum: llvm_unreachable("enum template");
437      }
438      VisitTemplateParameterList(ClassTmpl->getTemplateParameters());
439    } else if (const ClassTemplatePartialSpecializationDecl *PartialSpec
440                = dyn_cast<ClassTemplatePartialSpecializationDecl>(CXXRecord)) {
441      AlreadyStarted = true;
442
443      switch (D->getTagKind()) {
444      case TTK_Interface:
445      case TTK_Class:
446      case TTK_Struct: Out << "@SP"; break;
447      case TTK_Union:  Out << "@UP"; break;
448      case TTK_Enum: llvm_unreachable("enum partial specialization");
449      }
450      VisitTemplateParameterList(PartialSpec->getTemplateParameters());
451    }
452  }
453
454  if (!AlreadyStarted) {
455    switch (D->getTagKind()) {
456      case TTK_Interface:
457      case TTK_Class:
458      case TTK_Struct: Out << "@S"; break;
459      case TTK_Union:  Out << "@U"; break;
460      case TTK_Enum:   Out << "@E"; break;
461    }
462  }
463
464  Out << '@';
465  Out.flush();
466  assert(Buf.size() > 0);
467  const unsigned off = Buf.size() - 1;
468
469  if (EmitDeclName(D)) {
470    if (const TypedefNameDecl *TD = D->getTypedefNameForAnonDecl()) {
471      Buf[off] = 'A';
472      Out << '@' << *TD;
473    }
474  else {
475    if (D->isEmbeddedInDeclarator() && !D->isFreeStanding()) {
476      printLoc(Out, D->getLocation(), Context->getSourceManager(), true);
477    } else
478      Buf[off] = 'a';
479  }
480  }
481
482  // For a class template specialization, mangle the template arguments.
483  if (const ClassTemplateSpecializationDecl *Spec
484                              = dyn_cast<ClassTemplateSpecializationDecl>(D)) {
485    const TemplateArgumentList &Args = Spec->getTemplateInstantiationArgs();
486    Out << '>';
487    for (unsigned I = 0, N = Args.size(); I != N; ++I) {
488      Out << '#';
489      VisitTemplateArgument(Args.get(I));
490    }
491  }
492}
493
494void USRGenerator::VisitTypedefDecl(const TypedefDecl *D) {
495  if (ShouldGenerateLocation(D) && GenLoc(D, /*IncludeOffset=*/isLocal(D)))
496    return;
497  const DeclContext *DC = D->getDeclContext();
498  if (const NamedDecl *DCN = dyn_cast<NamedDecl>(DC))
499    Visit(DCN);
500  Out << "@T@";
501  Out << D->getName();
502}
503
504void USRGenerator::VisitTemplateTypeParmDecl(const TemplateTypeParmDecl *D) {
505  GenLoc(D, /*IncludeOffset=*/true);
506  return;
507}
508
509bool USRGenerator::GenLoc(const Decl *D, bool IncludeOffset) {
510  if (generatedLoc)
511    return IgnoreResults;
512  generatedLoc = true;
513
514  // Guard against null declarations in invalid code.
515  if (!D) {
516    IgnoreResults = true;
517    return true;
518  }
519
520  // Use the location of canonical decl.
521  D = D->getCanonicalDecl();
522
523  IgnoreResults =
524      IgnoreResults || printLoc(Out, D->getLocStart(),
525                                Context->getSourceManager(), IncludeOffset);
526
527  return IgnoreResults;
528}
529
530void USRGenerator::VisitType(QualType T) {
531  // This method mangles in USR information for types.  It can possibly
532  // just reuse the naming-mangling logic used by codegen, although the
533  // requirements for USRs might not be the same.
534  ASTContext &Ctx = *Context;
535
536  do {
537    T = Ctx.getCanonicalType(T);
538    Qualifiers Q = T.getQualifiers();
539    unsigned qVal = 0;
540    if (Q.hasConst())
541      qVal |= 0x1;
542    if (Q.hasVolatile())
543      qVal |= 0x2;
544    if (Q.hasRestrict())
545      qVal |= 0x4;
546    if(qVal)
547      Out << ((char) ('0' + qVal));
548
549    // Mangle in ObjC GC qualifiers?
550
551    if (const PackExpansionType *Expansion = T->getAs<PackExpansionType>()) {
552      Out << 'P';
553      T = Expansion->getPattern();
554    }
555
556    if (const BuiltinType *BT = T->getAs<BuiltinType>()) {
557      unsigned char c = '\0';
558      switch (BT->getKind()) {
559        case BuiltinType::Void:
560          c = 'v'; break;
561        case BuiltinType::Bool:
562          c = 'b'; break;
563        case BuiltinType::UChar:
564          c = 'c'; break;
565        case BuiltinType::Char16:
566          c = 'q'; break;
567        case BuiltinType::Char32:
568          c = 'w'; break;
569        case BuiltinType::UShort:
570          c = 's'; break;
571        case BuiltinType::UInt:
572          c = 'i'; break;
573        case BuiltinType::ULong:
574          c = 'l'; break;
575        case BuiltinType::ULongLong:
576          c = 'k'; break;
577        case BuiltinType::UInt128:
578          c = 'j'; break;
579        case BuiltinType::Char_U:
580        case BuiltinType::Char_S:
581          c = 'C'; break;
582        case BuiltinType::SChar:
583          c = 'r'; break;
584        case BuiltinType::WChar_S:
585        case BuiltinType::WChar_U:
586          c = 'W'; break;
587        case BuiltinType::Short:
588          c = 'S'; break;
589        case BuiltinType::Int:
590          c = 'I'; break;
591        case BuiltinType::Long:
592          c = 'L'; break;
593        case BuiltinType::LongLong:
594          c = 'K'; break;
595        case BuiltinType::Int128:
596          c = 'J'; break;
597        case BuiltinType::Half:
598          c = 'h'; break;
599        case BuiltinType::Float:
600          c = 'f'; break;
601        case BuiltinType::Double:
602          c = 'd'; break;
603        case BuiltinType::LongDouble:
604          c = 'D'; break;
605        case BuiltinType::NullPtr:
606          c = 'n'; break;
607#define BUILTIN_TYPE(Id, SingletonId)
608#define PLACEHOLDER_TYPE(Id, SingletonId) case BuiltinType::Id:
609#include "clang/AST/BuiltinTypes.def"
610        case BuiltinType::Dependent:
611        case BuiltinType::OCLImage1d:
612        case BuiltinType::OCLImage1dArray:
613        case BuiltinType::OCLImage1dBuffer:
614        case BuiltinType::OCLImage2d:
615        case BuiltinType::OCLImage2dArray:
616        case BuiltinType::OCLImage3d:
617        case BuiltinType::OCLEvent:
618        case BuiltinType::OCLSampler:
619          IgnoreResults = true;
620          return;
621        case BuiltinType::ObjCId:
622          c = 'o'; break;
623        case BuiltinType::ObjCClass:
624          c = 'O'; break;
625        case BuiltinType::ObjCSel:
626          c = 'e'; break;
627      }
628      Out << c;
629      return;
630    }
631
632    // If we have already seen this (non-built-in) type, use a substitution
633    // encoding.
634    llvm::DenseMap<const Type *, unsigned>::iterator Substitution
635      = TypeSubstitutions.find(T.getTypePtr());
636    if (Substitution != TypeSubstitutions.end()) {
637      Out << 'S' << Substitution->second << '_';
638      return;
639    } else {
640      // Record this as a substitution.
641      unsigned Number = TypeSubstitutions.size();
642      TypeSubstitutions[T.getTypePtr()] = Number;
643    }
644
645    if (const PointerType *PT = T->getAs<PointerType>()) {
646      Out << '*';
647      T = PT->getPointeeType();
648      continue;
649    }
650    if (const RValueReferenceType *RT = T->getAs<RValueReferenceType>()) {
651      Out << "&&";
652      T = RT->getPointeeType();
653      continue;
654    }
655    if (const ReferenceType *RT = T->getAs<ReferenceType>()) {
656      Out << '&';
657      T = RT->getPointeeType();
658      continue;
659    }
660    if (const FunctionProtoType *FT = T->getAs<FunctionProtoType>()) {
661      Out << 'F';
662      VisitType(FT->getReturnType());
663      for (const auto &I : FT->param_types())
664        VisitType(I);
665      if (FT->isVariadic())
666        Out << '.';
667      return;
668    }
669    if (const BlockPointerType *BT = T->getAs<BlockPointerType>()) {
670      Out << 'B';
671      T = BT->getPointeeType();
672      continue;
673    }
674    if (const ComplexType *CT = T->getAs<ComplexType>()) {
675      Out << '<';
676      T = CT->getElementType();
677      continue;
678    }
679    if (const TagType *TT = T->getAs<TagType>()) {
680      Out << '$';
681      VisitTagDecl(TT->getDecl());
682      return;
683    }
684    if (const TemplateTypeParmType *TTP = T->getAs<TemplateTypeParmType>()) {
685      Out << 't' << TTP->getDepth() << '.' << TTP->getIndex();
686      return;
687    }
688    if (const TemplateSpecializationType *Spec
689                                    = T->getAs<TemplateSpecializationType>()) {
690      Out << '>';
691      VisitTemplateName(Spec->getTemplateName());
692      Out << Spec->getNumArgs();
693      for (unsigned I = 0, N = Spec->getNumArgs(); I != N; ++I)
694        VisitTemplateArgument(Spec->getArg(I));
695      return;
696    }
697    if (const DependentNameType *DNT = T->getAs<DependentNameType>()) {
698      Out << '^';
699      // FIXME: Encode the qualifier, don't just print it.
700      PrintingPolicy PO(Ctx.getLangOpts());
701      PO.SuppressTagKeyword = true;
702      PO.SuppressUnwrittenScope = true;
703      PO.ConstantArraySizeAsWritten = false;
704      PO.AnonymousTagLocations = false;
705      DNT->getQualifier()->print(Out, PO);
706      Out << ':' << DNT->getIdentifier()->getName();
707      return;
708    }
709    if (const InjectedClassNameType *InjT = T->getAs<InjectedClassNameType>()) {
710      T = InjT->getInjectedSpecializationType();
711      continue;
712    }
713
714    // Unhandled type.
715    Out << ' ';
716    break;
717  } while (true);
718}
719
720void USRGenerator::VisitTemplateParameterList(
721                                         const TemplateParameterList *Params) {
722  if (!Params)
723    return;
724  Out << '>' << Params->size();
725  for (TemplateParameterList::const_iterator P = Params->begin(),
726                                          PEnd = Params->end();
727       P != PEnd; ++P) {
728    Out << '#';
729    if (isa<TemplateTypeParmDecl>(*P)) {
730      if (cast<TemplateTypeParmDecl>(*P)->isParameterPack())
731        Out<< 'p';
732      Out << 'T';
733      continue;
734    }
735
736    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
737      if (NTTP->isParameterPack())
738        Out << 'p';
739      Out << 'N';
740      VisitType(NTTP->getType());
741      continue;
742    }
743
744    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
745    if (TTP->isParameterPack())
746      Out << 'p';
747    Out << 't';
748    VisitTemplateParameterList(TTP->getTemplateParameters());
749  }
750}
751
752void USRGenerator::VisitTemplateName(TemplateName Name) {
753  if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
754    if (TemplateTemplateParmDecl *TTP
755                              = dyn_cast<TemplateTemplateParmDecl>(Template)) {
756      Out << 't' << TTP->getDepth() << '.' << TTP->getIndex();
757      return;
758    }
759
760    Visit(Template);
761    return;
762  }
763
764  // FIXME: Visit dependent template names.
765}
766
767void USRGenerator::VisitTemplateArgument(const TemplateArgument &Arg) {
768  switch (Arg.getKind()) {
769  case TemplateArgument::Null:
770    break;
771
772  case TemplateArgument::Declaration:
773    Visit(Arg.getAsDecl());
774    break;
775
776  case TemplateArgument::NullPtr:
777    break;
778
779  case TemplateArgument::TemplateExpansion:
780    Out << 'P'; // pack expansion of...
781    // Fall through
782  case TemplateArgument::Template:
783    VisitTemplateName(Arg.getAsTemplateOrTemplatePattern());
784    break;
785
786  case TemplateArgument::Expression:
787    // FIXME: Visit expressions.
788    break;
789
790  case TemplateArgument::Pack:
791    Out << 'p' << Arg.pack_size();
792    for (const auto &P : Arg.pack_elements())
793      VisitTemplateArgument(P);
794    break;
795
796  case TemplateArgument::Type:
797    VisitType(Arg.getAsType());
798    break;
799
800  case TemplateArgument::Integral:
801    Out << 'V';
802    VisitType(Arg.getIntegralType());
803    Out << Arg.getAsIntegral();
804    break;
805  }
806}
807
808//===----------------------------------------------------------------------===//
809// USR generation functions.
810//===----------------------------------------------------------------------===//
811
812void clang::index::generateUSRForObjCClass(StringRef Cls, raw_ostream &OS) {
813  OS << "objc(cs)" << Cls;
814}
815
816void clang::index::generateUSRForObjCCategory(StringRef Cls, StringRef Cat,
817                                              raw_ostream &OS) {
818  OS << "objc(cy)" << Cls << '@' << Cat;
819}
820
821void clang::index::generateUSRForObjCIvar(StringRef Ivar, raw_ostream &OS) {
822  OS << '@' << Ivar;
823}
824
825void clang::index::generateUSRForObjCMethod(StringRef Sel,
826                                            bool IsInstanceMethod,
827                                            raw_ostream &OS) {
828  OS << (IsInstanceMethod ? "(im)" : "(cm)") << Sel;
829}
830
831void clang::index::generateUSRForObjCProperty(StringRef Prop, raw_ostream &OS) {
832  OS << "(py)" << Prop;
833}
834
835void clang::index::generateUSRForObjCProtocol(StringRef Prot, raw_ostream &OS) {
836  OS << "objc(pl)" << Prot;
837}
838
839bool clang::index::generateUSRForDecl(const Decl *D,
840                                      SmallVectorImpl<char> &Buf) {
841  // Don't generate USRs for things with invalid locations.
842  if (!D || D->getLocStart().isInvalid())
843    return true;
844
845  USRGenerator UG(&D->getASTContext(), Buf);
846  UG.Visit(D);
847  return UG.ignoreResults();
848}
849
850bool clang::index::generateUSRForMacro(const MacroDefinition *MD,
851                                       const SourceManager &SM,
852                                       SmallVectorImpl<char> &Buf) {
853  // Don't generate USRs for things with invalid locations.
854  if (!MD || MD->getLocation().isInvalid())
855    return true;
856
857  llvm::raw_svector_ostream Out(Buf);
858
859  // Assume that system headers are sane.  Don't put source location
860  // information into the USR if the macro comes from a system header.
861  SourceLocation Loc = MD->getLocation();
862  bool ShouldGenerateLocation = !SM.isInSystemHeader(Loc);
863
864  Out << getUSRSpacePrefix();
865  if (ShouldGenerateLocation)
866    printLoc(Out, Loc, SM, /*IncludeOffset=*/true);
867  Out << "@macro@";
868  Out << MD->getName()->getName();
869  return false;
870}
871
872