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  if (FunctionTemplateDecl *FunTmpl = D->getDescribedFunctionTemplate()) {
202    Out << "@FT@";
203    VisitTemplateParameterList(FunTmpl->getTemplateParameters());
204  } else
205    Out << "@F@";
206  D->printName(Out);
207
208  ASTContext &Ctx = *Context;
209  if (!Ctx.getLangOpts().CPlusPlus || D->isExternC())
210    return;
211
212  if (const TemplateArgumentList *
213        SpecArgs = D->getTemplateSpecializationArgs()) {
214    Out << '<';
215    for (unsigned I = 0, N = SpecArgs->size(); I != N; ++I) {
216      Out << '#';
217      VisitTemplateArgument(SpecArgs->get(I));
218    }
219    Out << '>';
220  }
221
222  // Mangle in type information for the arguments.
223  for (auto PD : D->params()) {
224    Out << '#';
225    VisitType(PD->getType());
226  }
227  if (D->isVariadic())
228    Out << '.';
229  Out << '#';
230  if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
231    if (MD->isStatic())
232      Out << 'S';
233    if (unsigned quals = MD->getTypeQualifiers())
234      Out << (char)('0' + quals);
235  }
236}
237
238void USRGenerator::VisitNamedDecl(const NamedDecl *D) {
239  VisitDeclContext(D->getDeclContext());
240  Out << "@";
241
242  if (EmitDeclName(D)) {
243    // The string can be empty if the declaration has no name; e.g., it is
244    // the ParmDecl with no name for declaration of a function pointer type,
245    // e.g.: void  (*f)(void *);
246    // In this case, don't generate a USR.
247    IgnoreResults = true;
248  }
249}
250
251void USRGenerator::VisitVarDecl(const VarDecl *D) {
252  // VarDecls can be declared 'extern' within a function or method body,
253  // but their enclosing DeclContext is the function, not the TU.  We need
254  // to check the storage class to correctly generate the USR.
255  if (ShouldGenerateLocation(D) && GenLoc(D, /*IncludeOffset=*/isLocal(D)))
256    return;
257
258  VisitDeclContext(D->getDeclContext());
259
260  // Variables always have simple names.
261  StringRef s = D->getName();
262
263  // The string can be empty if the declaration has no name; e.g., it is
264  // the ParmDecl with no name for declaration of a function pointer type, e.g.:
265  //    void  (*f)(void *);
266  // In this case, don't generate a USR.
267  if (s.empty())
268    IgnoreResults = true;
269  else
270    Out << '@' << s;
271}
272
273void USRGenerator::VisitNonTypeTemplateParmDecl(
274                                        const NonTypeTemplateParmDecl *D) {
275  GenLoc(D, /*IncludeOffset=*/true);
276  return;
277}
278
279void USRGenerator::VisitTemplateTemplateParmDecl(
280                                        const TemplateTemplateParmDecl *D) {
281  GenLoc(D, /*IncludeOffset=*/true);
282  return;
283}
284
285void USRGenerator::VisitNamespaceDecl(const NamespaceDecl *D) {
286  if (D->isAnonymousNamespace()) {
287    Out << "@aN";
288    return;
289  }
290
291  VisitDeclContext(D->getDeclContext());
292  if (!IgnoreResults)
293    Out << "@N@" << D->getName();
294}
295
296void USRGenerator::VisitFunctionTemplateDecl(const FunctionTemplateDecl *D) {
297  VisitFunctionDecl(D->getTemplatedDecl());
298}
299
300void USRGenerator::VisitClassTemplateDecl(const ClassTemplateDecl *D) {
301  VisitTagDecl(D->getTemplatedDecl());
302}
303
304void USRGenerator::VisitNamespaceAliasDecl(const NamespaceAliasDecl *D) {
305  VisitDeclContext(D->getDeclContext());
306  if (!IgnoreResults)
307    Out << "@NA@" << D->getName();
308}
309
310void USRGenerator::VisitObjCMethodDecl(const ObjCMethodDecl *D) {
311  const DeclContext *container = D->getDeclContext();
312  if (const ObjCProtocolDecl *pd = dyn_cast<ObjCProtocolDecl>(container)) {
313    Visit(pd);
314  }
315  else {
316    // The USR for a method declared in a class extension or category is based on
317    // the ObjCInterfaceDecl, not the ObjCCategoryDecl.
318    const ObjCInterfaceDecl *ID = D->getClassInterface();
319    if (!ID) {
320      IgnoreResults = true;
321      return;
322    }
323    Visit(ID);
324  }
325  // Ideally we would use 'GenObjCMethod', but this is such a hot path
326  // for Objective-C code that we don't want to use
327  // DeclarationName::getAsString().
328  Out << (D->isInstanceMethod() ? "(im)" : "(cm)")
329      << DeclarationName(D->getSelector());
330}
331
332void USRGenerator::VisitObjCContainerDecl(const ObjCContainerDecl *D) {
333  switch (D->getKind()) {
334    default:
335      llvm_unreachable("Invalid ObjC container.");
336    case Decl::ObjCInterface:
337    case Decl::ObjCImplementation:
338      GenObjCClass(D->getName());
339      break;
340    case Decl::ObjCCategory: {
341      const ObjCCategoryDecl *CD = cast<ObjCCategoryDecl>(D);
342      const ObjCInterfaceDecl *ID = CD->getClassInterface();
343      if (!ID) {
344        // Handle invalid code where the @interface might not
345        // have been specified.
346        // FIXME: We should be able to generate this USR even if the
347        // @interface isn't available.
348        IgnoreResults = true;
349        return;
350      }
351      // Specially handle class extensions, which are anonymous categories.
352      // We want to mangle in the location to uniquely distinguish them.
353      if (CD->IsClassExtension()) {
354        Out << "objc(ext)" << ID->getName() << '@';
355        GenLoc(CD, /*IncludeOffset=*/true);
356      }
357      else
358        GenObjCCategory(ID->getName(), CD->getName());
359
360      break;
361    }
362    case Decl::ObjCCategoryImpl: {
363      const ObjCCategoryImplDecl *CD = cast<ObjCCategoryImplDecl>(D);
364      const ObjCInterfaceDecl *ID = CD->getClassInterface();
365      if (!ID) {
366        // Handle invalid code where the @interface might not
367        // have been specified.
368        // FIXME: We should be able to generate this USR even if the
369        // @interface isn't available.
370        IgnoreResults = true;
371        return;
372      }
373      GenObjCCategory(ID->getName(), CD->getName());
374      break;
375    }
376    case Decl::ObjCProtocol:
377      GenObjCProtocol(cast<ObjCProtocolDecl>(D)->getName());
378      break;
379  }
380}
381
382void USRGenerator::VisitObjCPropertyDecl(const ObjCPropertyDecl *D) {
383  // The USR for a property declared in a class extension or category is based
384  // on the ObjCInterfaceDecl, not the ObjCCategoryDecl.
385  if (const ObjCInterfaceDecl *ID = Context->getObjContainingInterface(D))
386    Visit(ID);
387  else
388    Visit(cast<Decl>(D->getDeclContext()));
389  GenObjCProperty(D->getName());
390}
391
392void USRGenerator::VisitObjCPropertyImplDecl(const ObjCPropertyImplDecl *D) {
393  if (ObjCPropertyDecl *PD = D->getPropertyDecl()) {
394    VisitObjCPropertyDecl(PD);
395    return;
396  }
397
398  IgnoreResults = true;
399}
400
401void USRGenerator::VisitTagDecl(const TagDecl *D) {
402  // Add the location of the tag decl to handle resolution across
403  // translation units.
404  if (ShouldGenerateLocation(D) && GenLoc(D, /*IncludeOffset=*/isLocal(D)))
405    return;
406
407  D = D->getCanonicalDecl();
408  VisitDeclContext(D->getDeclContext());
409
410  bool AlreadyStarted = false;
411  if (const CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(D)) {
412    if (ClassTemplateDecl *ClassTmpl = CXXRecord->getDescribedClassTemplate()) {
413      AlreadyStarted = true;
414
415      switch (D->getTagKind()) {
416      case TTK_Interface:
417      case TTK_Struct: Out << "@ST"; break;
418      case TTK_Class:  Out << "@CT"; break;
419      case TTK_Union:  Out << "@UT"; break;
420      case TTK_Enum: llvm_unreachable("enum template");
421      }
422      VisitTemplateParameterList(ClassTmpl->getTemplateParameters());
423    } else if (const ClassTemplatePartialSpecializationDecl *PartialSpec
424                = dyn_cast<ClassTemplatePartialSpecializationDecl>(CXXRecord)) {
425      AlreadyStarted = true;
426
427      switch (D->getTagKind()) {
428      case TTK_Interface:
429      case TTK_Struct: Out << "@SP"; break;
430      case TTK_Class:  Out << "@CP"; break;
431      case TTK_Union:  Out << "@UP"; break;
432      case TTK_Enum: llvm_unreachable("enum partial specialization");
433      }
434      VisitTemplateParameterList(PartialSpec->getTemplateParameters());
435    }
436  }
437
438  if (!AlreadyStarted) {
439    switch (D->getTagKind()) {
440      case TTK_Interface:
441      case TTK_Struct: Out << "@S"; break;
442      case TTK_Class:  Out << "@C"; break;
443      case TTK_Union:  Out << "@U"; break;
444      case TTK_Enum:   Out << "@E"; break;
445    }
446  }
447
448  Out << '@';
449  Out.flush();
450  assert(Buf.size() > 0);
451  const unsigned off = Buf.size() - 1;
452
453  if (EmitDeclName(D)) {
454    if (const TypedefNameDecl *TD = D->getTypedefNameForAnonDecl()) {
455      Buf[off] = 'A';
456      Out << '@' << *TD;
457    }
458    else
459      Buf[off] = 'a';
460  }
461
462  // For a class template specialization, mangle the template arguments.
463  if (const ClassTemplateSpecializationDecl *Spec
464                              = dyn_cast<ClassTemplateSpecializationDecl>(D)) {
465    const TemplateArgumentList &Args = Spec->getTemplateInstantiationArgs();
466    Out << '>';
467    for (unsigned I = 0, N = Args.size(); I != N; ++I) {
468      Out << '#';
469      VisitTemplateArgument(Args.get(I));
470    }
471  }
472}
473
474void USRGenerator::VisitTypedefDecl(const TypedefDecl *D) {
475  if (ShouldGenerateLocation(D) && GenLoc(D, /*IncludeOffset=*/isLocal(D)))
476    return;
477  const DeclContext *DC = D->getDeclContext();
478  if (const NamedDecl *DCN = dyn_cast<NamedDecl>(DC))
479    Visit(DCN);
480  Out << "@T@";
481  Out << D->getName();
482}
483
484void USRGenerator::VisitTemplateTypeParmDecl(const TemplateTypeParmDecl *D) {
485  GenLoc(D, /*IncludeOffset=*/true);
486  return;
487}
488
489bool USRGenerator::GenLoc(const Decl *D, bool IncludeOffset) {
490  if (generatedLoc)
491    return IgnoreResults;
492  generatedLoc = true;
493
494  // Guard against null declarations in invalid code.
495  if (!D) {
496    IgnoreResults = true;
497    return true;
498  }
499
500  // Use the location of canonical decl.
501  D = D->getCanonicalDecl();
502
503  IgnoreResults =
504      IgnoreResults || printLoc(Out, D->getLocStart(),
505                                Context->getSourceManager(), IncludeOffset);
506
507  return IgnoreResults;
508}
509
510void USRGenerator::VisitType(QualType T) {
511  // This method mangles in USR information for types.  It can possibly
512  // just reuse the naming-mangling logic used by codegen, although the
513  // requirements for USRs might not be the same.
514  ASTContext &Ctx = *Context;
515
516  do {
517    T = Ctx.getCanonicalType(T);
518    Qualifiers Q = T.getQualifiers();
519    unsigned qVal = 0;
520    if (Q.hasConst())
521      qVal |= 0x1;
522    if (Q.hasVolatile())
523      qVal |= 0x2;
524    if (Q.hasRestrict())
525      qVal |= 0x4;
526    if(qVal)
527      Out << ((char) ('0' + qVal));
528
529    // Mangle in ObjC GC qualifiers?
530
531    if (const PackExpansionType *Expansion = T->getAs<PackExpansionType>()) {
532      Out << 'P';
533      T = Expansion->getPattern();
534    }
535
536    if (const BuiltinType *BT = T->getAs<BuiltinType>()) {
537      unsigned char c = '\0';
538      switch (BT->getKind()) {
539        case BuiltinType::Void:
540          c = 'v'; break;
541        case BuiltinType::Bool:
542          c = 'b'; break;
543        case BuiltinType::Char_U:
544        case BuiltinType::UChar:
545          c = 'c'; break;
546        case BuiltinType::Char16:
547          c = 'q'; break;
548        case BuiltinType::Char32:
549          c = 'w'; break;
550        case BuiltinType::UShort:
551          c = 's'; break;
552        case BuiltinType::UInt:
553          c = 'i'; break;
554        case BuiltinType::ULong:
555          c = 'l'; break;
556        case BuiltinType::ULongLong:
557          c = 'k'; break;
558        case BuiltinType::UInt128:
559          c = 'j'; break;
560        case BuiltinType::Char_S:
561        case BuiltinType::SChar:
562          c = 'C'; break;
563        case BuiltinType::WChar_S:
564        case BuiltinType::WChar_U:
565          c = 'W'; break;
566        case BuiltinType::Short:
567          c = 'S'; break;
568        case BuiltinType::Int:
569          c = 'I'; break;
570        case BuiltinType::Long:
571          c = 'L'; break;
572        case BuiltinType::LongLong:
573          c = 'K'; break;
574        case BuiltinType::Int128:
575          c = 'J'; break;
576        case BuiltinType::Half:
577          c = 'h'; break;
578        case BuiltinType::Float:
579          c = 'f'; break;
580        case BuiltinType::Double:
581          c = 'd'; break;
582        case BuiltinType::LongDouble:
583          c = 'D'; break;
584        case BuiltinType::NullPtr:
585          c = 'n'; break;
586#define BUILTIN_TYPE(Id, SingletonId)
587#define PLACEHOLDER_TYPE(Id, SingletonId) case BuiltinType::Id:
588#include "clang/AST/BuiltinTypes.def"
589        case BuiltinType::Dependent:
590        case BuiltinType::OCLImage1d:
591        case BuiltinType::OCLImage1dArray:
592        case BuiltinType::OCLImage1dBuffer:
593        case BuiltinType::OCLImage2d:
594        case BuiltinType::OCLImage2dArray:
595        case BuiltinType::OCLImage3d:
596        case BuiltinType::OCLEvent:
597        case BuiltinType::OCLSampler:
598          IgnoreResults = true;
599          return;
600        case BuiltinType::ObjCId:
601          c = 'o'; break;
602        case BuiltinType::ObjCClass:
603          c = 'O'; break;
604        case BuiltinType::ObjCSel:
605          c = 'e'; break;
606      }
607      Out << c;
608      return;
609    }
610
611    // If we have already seen this (non-built-in) type, use a substitution
612    // encoding.
613    llvm::DenseMap<const Type *, unsigned>::iterator Substitution
614      = TypeSubstitutions.find(T.getTypePtr());
615    if (Substitution != TypeSubstitutions.end()) {
616      Out << 'S' << Substitution->second << '_';
617      return;
618    } else {
619      // Record this as a substitution.
620      unsigned Number = TypeSubstitutions.size();
621      TypeSubstitutions[T.getTypePtr()] = Number;
622    }
623
624    if (const PointerType *PT = T->getAs<PointerType>()) {
625      Out << '*';
626      T = PT->getPointeeType();
627      continue;
628    }
629    if (const ReferenceType *RT = T->getAs<ReferenceType>()) {
630      Out << '&';
631      T = RT->getPointeeType();
632      continue;
633    }
634    if (const FunctionProtoType *FT = T->getAs<FunctionProtoType>()) {
635      Out << 'F';
636      VisitType(FT->getReturnType());
637      for (const auto &I : FT->param_types())
638        VisitType(I);
639      if (FT->isVariadic())
640        Out << '.';
641      return;
642    }
643    if (const BlockPointerType *BT = T->getAs<BlockPointerType>()) {
644      Out << 'B';
645      T = BT->getPointeeType();
646      continue;
647    }
648    if (const ComplexType *CT = T->getAs<ComplexType>()) {
649      Out << '<';
650      T = CT->getElementType();
651      continue;
652    }
653    if (const TagType *TT = T->getAs<TagType>()) {
654      Out << '$';
655      VisitTagDecl(TT->getDecl());
656      return;
657    }
658    if (const TemplateTypeParmType *TTP = T->getAs<TemplateTypeParmType>()) {
659      Out << 't' << TTP->getDepth() << '.' << TTP->getIndex();
660      return;
661    }
662    if (const TemplateSpecializationType *Spec
663                                    = T->getAs<TemplateSpecializationType>()) {
664      Out << '>';
665      VisitTemplateName(Spec->getTemplateName());
666      Out << Spec->getNumArgs();
667      for (unsigned I = 0, N = Spec->getNumArgs(); I != N; ++I)
668        VisitTemplateArgument(Spec->getArg(I));
669      return;
670    }
671
672    // Unhandled type.
673    Out << ' ';
674    break;
675  } while (true);
676}
677
678void USRGenerator::VisitTemplateParameterList(
679                                         const TemplateParameterList *Params) {
680  if (!Params)
681    return;
682  Out << '>' << Params->size();
683  for (TemplateParameterList::const_iterator P = Params->begin(),
684                                          PEnd = Params->end();
685       P != PEnd; ++P) {
686    Out << '#';
687    if (isa<TemplateTypeParmDecl>(*P)) {
688      if (cast<TemplateTypeParmDecl>(*P)->isParameterPack())
689        Out<< 'p';
690      Out << 'T';
691      continue;
692    }
693
694    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
695      if (NTTP->isParameterPack())
696        Out << 'p';
697      Out << 'N';
698      VisitType(NTTP->getType());
699      continue;
700    }
701
702    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
703    if (TTP->isParameterPack())
704      Out << 'p';
705    Out << 't';
706    VisitTemplateParameterList(TTP->getTemplateParameters());
707  }
708}
709
710void USRGenerator::VisitTemplateName(TemplateName Name) {
711  if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
712    if (TemplateTemplateParmDecl *TTP
713                              = dyn_cast<TemplateTemplateParmDecl>(Template)) {
714      Out << 't' << TTP->getDepth() << '.' << TTP->getIndex();
715      return;
716    }
717
718    Visit(Template);
719    return;
720  }
721
722  // FIXME: Visit dependent template names.
723}
724
725void USRGenerator::VisitTemplateArgument(const TemplateArgument &Arg) {
726  switch (Arg.getKind()) {
727  case TemplateArgument::Null:
728    break;
729
730  case TemplateArgument::Declaration:
731    Visit(Arg.getAsDecl());
732    break;
733
734  case TemplateArgument::NullPtr:
735    break;
736
737  case TemplateArgument::TemplateExpansion:
738    Out << 'P'; // pack expansion of...
739    // Fall through
740  case TemplateArgument::Template:
741    VisitTemplateName(Arg.getAsTemplateOrTemplatePattern());
742    break;
743
744  case TemplateArgument::Expression:
745    // FIXME: Visit expressions.
746    break;
747
748  case TemplateArgument::Pack:
749    Out << 'p' << Arg.pack_size();
750    for (TemplateArgument::pack_iterator P = Arg.pack_begin(), PEnd = Arg.pack_end();
751         P != PEnd; ++P)
752      VisitTemplateArgument(*P);
753    break;
754
755  case TemplateArgument::Type:
756    VisitType(Arg.getAsType());
757    break;
758
759  case TemplateArgument::Integral:
760    Out << 'V';
761    VisitType(Arg.getIntegralType());
762    Out << Arg.getAsIntegral();
763    break;
764  }
765}
766
767//===----------------------------------------------------------------------===//
768// USR generation functions.
769//===----------------------------------------------------------------------===//
770
771void clang::index::generateUSRForObjCClass(StringRef Cls, raw_ostream &OS) {
772  OS << "objc(cs)" << Cls;
773}
774
775void clang::index::generateUSRForObjCCategory(StringRef Cls, StringRef Cat,
776                                              raw_ostream &OS) {
777  OS << "objc(cy)" << Cls << '@' << Cat;
778}
779
780void clang::index::generateUSRForObjCIvar(StringRef Ivar, raw_ostream &OS) {
781  OS << '@' << Ivar;
782}
783
784void clang::index::generateUSRForObjCMethod(StringRef Sel,
785                                            bool IsInstanceMethod,
786                                            raw_ostream &OS) {
787  OS << (IsInstanceMethod ? "(im)" : "(cm)") << Sel;
788}
789
790void clang::index::generateUSRForObjCProperty(StringRef Prop, raw_ostream &OS) {
791  OS << "(py)" << Prop;
792}
793
794void clang::index::generateUSRForObjCProtocol(StringRef Prot, raw_ostream &OS) {
795  OS << "objc(pl)" << Prot;
796}
797
798bool clang::index::generateUSRForDecl(const Decl *D,
799                                      SmallVectorImpl<char> &Buf) {
800  // Don't generate USRs for things with invalid locations.
801  if (!D || D->getLocStart().isInvalid())
802    return true;
803
804  USRGenerator UG(&D->getASTContext(), Buf);
805  UG.Visit(D);
806  return UG.ignoreResults();
807}
808
809bool clang::index::generateUSRForMacro(const MacroDefinition *MD,
810                                       const SourceManager &SM,
811                                       SmallVectorImpl<char> &Buf) {
812  // Don't generate USRs for things with invalid locations.
813  if (!MD || MD->getLocation().isInvalid())
814    return true;
815
816  llvm::raw_svector_ostream Out(Buf);
817
818  // Assume that system headers are sane.  Don't put source location
819  // information into the USR if the macro comes from a system header.
820  SourceLocation Loc = MD->getLocation();
821  bool ShouldGenerateLocation = !SM.isInSystemHeader(Loc);
822
823  Out << getUSRSpacePrefix();
824  if (ShouldGenerateLocation)
825    printLoc(Out, Loc, SM, /*IncludeOffset=*/true);
826  Out << "@macro@";
827  Out << MD->getName()->getName();
828  return false;
829}
830
831