vendor/clang/clang-release_34-r197841

1 files changed, 34 insertions, 814 deletions

diff --git a/tools/libclang/CIndexUSRs.cpp b/tools/libclang/CIndexUSRs.cpp
index a911ce5e952a..2b43c5b375f5 100644
--- a/tools/libclang/CIndexUSRs.cpp
+++ b/tools/libclang/CIndexUSRs.cpp
@@ -14,787 +14,13 @@
 #include "CIndexer.h"
 #include "CXCursor.h"
 #include "CXString.h"
-#include "clang/AST/DeclTemplate.h"
-#include "clang/AST/DeclVisitor.h"
-#include "clang/Frontend/ASTUnit.h"
+#include "clang/Index/USRGeneration.h"
 #include "clang/Lex/PreprocessingRecord.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/Support/raw_ostream.h"
 
 using namespace clang;
-
-//===----------------------------------------------------------------------===//
-// USR generation.
-//===----------------------------------------------------------------------===//
-
-namespace {
-class USRGenerator : public ConstDeclVisitor<USRGenerator> {
-  OwningPtr<SmallString<128> > OwnedBuf;
-  SmallVectorImpl<char> &Buf;
-  llvm::raw_svector_ostream Out;
-  bool IgnoreResults;
-  ASTContext *Context;
-  bool generatedLoc;
-  
-  llvm::DenseMap<const Type *, unsigned> TypeSubstitutions;
-  
-public:
-  explicit USRGenerator(ASTContext *Ctx = 0, SmallVectorImpl<char> *extBuf = 0)
-  : OwnedBuf(extBuf ? 0 : new SmallString<128>()),
-    Buf(extBuf ? *extBuf : *OwnedBuf.get()),
-    Out(Buf),
-    IgnoreResults(false),
-    Context(Ctx),
-    generatedLoc(false)
-  {
-    // Add the USR space prefix.
-    Out << "c:";
-  }
-
-  StringRef str() {
-    return Out.str();
-  }
-
-  USRGenerator* operator->() { return this; }
-
-  template <typename T>
-  llvm::raw_svector_ostream &operator<<(const T &x) {
-    Out << x;
-    return Out;
-  }
-
-  bool ignoreResults() const { return IgnoreResults; }
-
-  // Visitation methods from generating USRs from AST elements.
-  void VisitDeclContext(const DeclContext *D);
-  void VisitFieldDecl(const FieldDecl *D);
-  void VisitFunctionDecl(const FunctionDecl *D);
-  void VisitNamedDecl(const NamedDecl *D);
-  void VisitNamespaceDecl(const NamespaceDecl *D);
-  void VisitNamespaceAliasDecl(const NamespaceAliasDecl *D);
-  void VisitFunctionTemplateDecl(const FunctionTemplateDecl *D);
-  void VisitClassTemplateDecl(const ClassTemplateDecl *D);
-  void VisitObjCContainerDecl(const ObjCContainerDecl *CD);
-  void VisitObjCMethodDecl(const ObjCMethodDecl *MD);
-  void VisitObjCPropertyDecl(const ObjCPropertyDecl *D);
-  void VisitObjCPropertyImplDecl(const ObjCPropertyImplDecl *D);
-  void VisitTagDecl(const TagDecl *D);
-  void VisitTypedefDecl(const TypedefDecl *D);
-  void VisitTemplateTypeParmDecl(const TemplateTypeParmDecl *D);
-  void VisitVarDecl(const VarDecl *D);
-  void VisitNonTypeTemplateParmDecl(const NonTypeTemplateParmDecl *D);
-  void VisitTemplateTemplateParmDecl(const TemplateTemplateParmDecl *D);
-  void VisitLinkageSpecDecl(const LinkageSpecDecl *D) {
-    IgnoreResults = true;
-  }
-  void VisitUsingDirectiveDecl(const UsingDirectiveDecl *D) {
-    IgnoreResults = true;
-  }
-  void VisitUsingDecl(const UsingDecl *D) {
-    IgnoreResults = true;
-  }
-  void VisitUnresolvedUsingValueDecl(const UnresolvedUsingValueDecl *D) {
-    IgnoreResults = true;
-  }
-  void VisitUnresolvedUsingTypenameDecl(const UnresolvedUsingTypenameDecl *D) {
-    IgnoreResults = true;
-  }
-  
-  /// Generate the string component containing the location of the
-  ///  declaration.
-  bool GenLoc(const Decl *D);
-
-  /// String generation methods used both by the visitation methods
-  /// and from other clients that want to directly generate USRs.  These
-  /// methods do not construct complete USRs (which incorporate the parents
-  /// of an AST element), but only the fragments concerning the AST element
-  /// itself.
-
-  /// Generate a USR for an Objective-C class.
-  void GenObjCClass(StringRef cls);
-  /// Generate a USR for an Objective-C class category.
-  void GenObjCCategory(StringRef cls, StringRef cat);
-  /// Generate a USR fragment for an Objective-C instance variable.  The
-  /// complete USR can be created by concatenating the USR for the
-  /// encompassing class with this USR fragment.
-  void GenObjCIvar(StringRef ivar);
-  /// Generate a USR fragment for an Objective-C method.
-  void GenObjCMethod(StringRef sel, bool isInstanceMethod);
-  /// Generate a USR fragment for an Objective-C property.
-  void GenObjCProperty(StringRef prop);
-  /// Generate a USR for an Objective-C protocol.
-  void GenObjCProtocol(StringRef prot);
-
-  void VisitType(QualType T);
-  void VisitTemplateParameterList(const TemplateParameterList *Params);
-  void VisitTemplateName(TemplateName Name);
-  void VisitTemplateArgument(const TemplateArgument &Arg);
-  
-  /// Emit a Decl's name using NamedDecl::printName() and return true if
-  ///  the decl had no name.
-  bool EmitDeclName(const NamedDecl *D);
-};
-
-} // end anonymous namespace
-
-//===----------------------------------------------------------------------===//
-// Generating USRs from ASTS.
-//===----------------------------------------------------------------------===//
-
-bool USRGenerator::EmitDeclName(const NamedDecl *D) {
-  Out.flush();
-  const unsigned startSize = Buf.size();
-  D->printName(Out);
-  Out.flush();
-  const unsigned endSize = Buf.size();
-  return startSize == endSize;
-}
-
-static inline bool ShouldGenerateLocation(const NamedDecl *D) {
-  return D->getLinkage() != ExternalLinkage;
-}
-
-void USRGenerator::VisitDeclContext(const DeclContext *DC) {
-  if (const NamedDecl *D = dyn_cast<NamedDecl>(DC))
-    Visit(D);
-}
-
-void USRGenerator::VisitFieldDecl(const FieldDecl *D) {
-  // The USR for an ivar declared in a class extension is based on the
-  // ObjCInterfaceDecl, not the ObjCCategoryDecl.
-  if (const ObjCInterfaceDecl *ID = Context->getObjContainingInterface(D))
-    Visit(ID);
-  else
-    VisitDeclContext(D->getDeclContext());
-  Out << (isa<ObjCIvarDecl>(D) ? "@" : "@FI@");
-  if (EmitDeclName(D)) {
-    // Bit fields can be anonymous.
-    IgnoreResults = true;
-    return;
-  }
-}
-
-void USRGenerator::VisitFunctionDecl(const FunctionDecl *D) {
-  if (ShouldGenerateLocation(D) && GenLoc(D))
-    return;
-
-  VisitDeclContext(D->getDeclContext());
-  if (FunctionTemplateDecl *FunTmpl = D->getDescribedFunctionTemplate()) {
-    Out << "@FT@";
-    VisitTemplateParameterList(FunTmpl->getTemplateParameters());
-  } else
-    Out << "@F@";
-  D->printName(Out);
-
-  ASTContext &Ctx = *Context;
-  if (!Ctx.getLangOpts().CPlusPlus || D->isExternC())
-    return;
-
-  if (const TemplateArgumentList *
-        SpecArgs = D->getTemplateSpecializationArgs()) {
-    Out << '<';
-    for (unsigned I = 0, N = SpecArgs->size(); I != N; ++I) {
-      Out << '#';
-      VisitTemplateArgument(SpecArgs->get(I));
-    }
-    Out << '>';
-  }
-
-  // Mangle in type information for the arguments.
-  for (FunctionDecl::param_const_iterator I = D->param_begin(),
-                                          E = D->param_end();
-       I != E; ++I) {
-    Out << '#';
-    if (ParmVarDecl *PD = *I)
-      VisitType(PD->getType());
-  }
-  if (D->isVariadic())
-    Out << '.';
-  Out << '#';
-  if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
-    if (MD->isStatic())
-      Out << 'S';
-    if (unsigned quals = MD->getTypeQualifiers())
-      Out << (char)('0' + quals);
-  }
-}
-
-void USRGenerator::VisitNamedDecl(const NamedDecl *D) {
-  VisitDeclContext(D->getDeclContext());
-  Out << "@";
-
-  if (EmitDeclName(D)) {
-    // The string can be empty if the declaration has no name; e.g., it is
-    // the ParmDecl with no name for declaration of a function pointer type,
-    // e.g.: void  (*f)(void *);
-    // In this case, don't generate a USR.
-    IgnoreResults = true;
-  }
-}
-
-void USRGenerator::VisitVarDecl(const VarDecl *D) {
-  // VarDecls can be declared 'extern' within a function or method body,
-  // but their enclosing DeclContext is the function, not the TU.  We need
-  // to check the storage class to correctly generate the USR.
-  if (ShouldGenerateLocation(D) && GenLoc(D))
-    return;
-
-  VisitDeclContext(D->getDeclContext());
-
-  // Variables always have simple names.
-  StringRef s = D->getName();
-
-  // The string can be empty if the declaration has no name; e.g., it is
-  // the ParmDecl with no name for declaration of a function pointer type, e.g.:
-  //    void  (*f)(void *);
-  // In this case, don't generate a USR.
-  if (s.empty())
-    IgnoreResults = true;
-  else
-    Out << '@' << s;
-}
-
-void USRGenerator::VisitNonTypeTemplateParmDecl(
-                                        const NonTypeTemplateParmDecl *D) {
-  GenLoc(D);
-  return;
-}
-
-void USRGenerator::VisitTemplateTemplateParmDecl(
-                                        const TemplateTemplateParmDecl *D) {
-  GenLoc(D);
-  return;
-}
-
-void USRGenerator::VisitNamespaceDecl(const NamespaceDecl *D) {
-  if (D->isAnonymousNamespace()) {
-    Out << "@aN";
-    return;
-  }
-
-  VisitDeclContext(D->getDeclContext());
-  if (!IgnoreResults)
-    Out << "@N@" << D->getName();
-}
-
-void USRGenerator::VisitFunctionTemplateDecl(const FunctionTemplateDecl *D) {
-  VisitFunctionDecl(D->getTemplatedDecl());
-}
-
-void USRGenerator::VisitClassTemplateDecl(const ClassTemplateDecl *D) {
-  VisitTagDecl(D->getTemplatedDecl());
-}
-
-void USRGenerator::VisitNamespaceAliasDecl(const NamespaceAliasDecl *D) {
-  VisitDeclContext(D->getDeclContext());
-  if (!IgnoreResults)
-    Out << "@NA@" << D->getName();  
-}
-
-void USRGenerator::VisitObjCMethodDecl(const ObjCMethodDecl *D) {
-  const DeclContext *container = D->getDeclContext();
-  if (const ObjCProtocolDecl *pd = dyn_cast<ObjCProtocolDecl>(container)) {
-    Visit(pd);
-  }
-  else {
-    // The USR for a method declared in a class extension or category is based on
-    // the ObjCInterfaceDecl, not the ObjCCategoryDecl.
-    const ObjCInterfaceDecl *ID = D->getClassInterface();
-    if (!ID) {
-      IgnoreResults = true;
-      return;
-    }
-    Visit(ID);
-  }
-  // Ideally we would use 'GenObjCMethod', but this is such a hot path
-  // for Objective-C code that we don't want to use
-  // DeclarationName::getAsString().
-  Out << (D->isInstanceMethod() ? "(im)" : "(cm)");
-  DeclarationName N(D->getSelector());
-  N.printName(Out);
-}
-
-void USRGenerator::VisitObjCContainerDecl(const ObjCContainerDecl *D) {
-  switch (D->getKind()) {
-    default:
-      llvm_unreachable("Invalid ObjC container.");
-    case Decl::ObjCInterface:
-    case Decl::ObjCImplementation:
-      GenObjCClass(D->getName());
-      break;
-    case Decl::ObjCCategory: {
-      const ObjCCategoryDecl *CD = cast<ObjCCategoryDecl>(D);
-      const ObjCInterfaceDecl *ID = CD->getClassInterface();
-      if (!ID) {
-        // Handle invalid code where the @interface might not
-        // have been specified.
-        // FIXME: We should be able to generate this USR even if the
-        // @interface isn't available.
-        IgnoreResults = true;
-        return;
-      }
-      // Specially handle class extensions, which are anonymous categories.
-      // We want to mangle in the location to uniquely distinguish them.
-      if (CD->IsClassExtension()) {
-        Out << "objc(ext)" << ID->getName() << '@';
-        GenLoc(CD);
-      }
-      else
-        GenObjCCategory(ID->getName(), CD->getName());
-
-      break;
-    }
-    case Decl::ObjCCategoryImpl: {
-      const ObjCCategoryImplDecl *CD = cast<ObjCCategoryImplDecl>(D);
-      const ObjCInterfaceDecl *ID = CD->getClassInterface();
-      if (!ID) {
-        // Handle invalid code where the @interface might not
-        // have been specified.
-        // FIXME: We should be able to generate this USR even if the
-        // @interface isn't available.
-        IgnoreResults = true;
-        return;
-      }
-      GenObjCCategory(ID->getName(), CD->getName());
-      break;
-    }
-    case Decl::ObjCProtocol:
-      GenObjCProtocol(cast<ObjCProtocolDecl>(D)->getName());
-      break;
-  }
-}
-
-void USRGenerator::VisitObjCPropertyDecl(const ObjCPropertyDecl *D) {
-  // The USR for a property declared in a class extension or category is based
-  // on the ObjCInterfaceDecl, not the ObjCCategoryDecl.
-  if (const ObjCInterfaceDecl *ID = Context->getObjContainingInterface(D))
-    Visit(ID);
-  else
-    Visit(cast<Decl>(D->getDeclContext()));
-  GenObjCProperty(D->getName());
-}
-
-void USRGenerator::VisitObjCPropertyImplDecl(const ObjCPropertyImplDecl *D) {
-  if (ObjCPropertyDecl *PD = D->getPropertyDecl()) {
-    VisitObjCPropertyDecl(PD);
-    return;
-  }
-
-  IgnoreResults = true;
-}
-
-void USRGenerator::VisitTagDecl(const TagDecl *D) {
-  // Add the location of the tag decl to handle resolution across
-  // translation units.
-  if (ShouldGenerateLocation(D) && GenLoc(D))
-    return;
-
-  D = D->getCanonicalDecl();
-  VisitDeclContext(D->getDeclContext());
-
-  bool AlreadyStarted = false;
-  if (const CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(D)) {
-    if (ClassTemplateDecl *ClassTmpl = CXXRecord->getDescribedClassTemplate()) {
-      AlreadyStarted = true;
-      
-      switch (D->getTagKind()) {
-      case TTK_Interface:
-      case TTK_Struct: Out << "@ST"; break;
-      case TTK_Class:  Out << "@CT"; break;
-      case TTK_Union:  Out << "@UT"; break;
-      case TTK_Enum: llvm_unreachable("enum template");
-      }
-      VisitTemplateParameterList(ClassTmpl->getTemplateParameters());
-    } else if (const ClassTemplatePartialSpecializationDecl *PartialSpec
-                = dyn_cast<ClassTemplatePartialSpecializationDecl>(CXXRecord)) {
-      AlreadyStarted = true;
-      
-      switch (D->getTagKind()) {
-      case TTK_Interface:
-      case TTK_Struct: Out << "@SP"; break;
-      case TTK_Class:  Out << "@CP"; break;
-      case TTK_Union:  Out << "@UP"; break;
-      case TTK_Enum: llvm_unreachable("enum partial specialization");
-      }      
-      VisitTemplateParameterList(PartialSpec->getTemplateParameters());
-    }
-  }
-  
-  if (!AlreadyStarted) {
-    switch (D->getTagKind()) {
-      case TTK_Interface:
-      case TTK_Struct: Out << "@S"; break;
-      case TTK_Class:  Out << "@C"; break;
-      case TTK_Union:  Out << "@U"; break;
-      case TTK_Enum:   Out << "@E"; break;
-    }
-  }
-  
-  Out << '@';
-  Out.flush();
-  assert(Buf.size() > 0);
-  const unsigned off = Buf.size() - 1;
-
-  if (EmitDeclName(D)) {
-    if (const TypedefNameDecl *TD = D->getTypedefNameForAnonDecl()) {
-      Buf[off] = 'A';
-      Out << '@' << *TD;
-    }
-    else
-      Buf[off] = 'a';
-  }
-  
-  // For a class template specialization, mangle the template arguments.
-  if (const ClassTemplateSpecializationDecl *Spec
-                              = dyn_cast<ClassTemplateSpecializationDecl>(D)) {
-    const TemplateArgumentList &Args = Spec->getTemplateInstantiationArgs();
-    Out << '>';
-    for (unsigned I = 0, N = Args.size(); I != N; ++I) {
-      Out << '#';
-      VisitTemplateArgument(Args.get(I));
-    }
-  }
-}
-
-void USRGenerator::VisitTypedefDecl(const TypedefDecl *D) {
-  if (ShouldGenerateLocation(D) && GenLoc(D))
-    return;
-  const DeclContext *DC = D->getDeclContext();
-  if (const NamedDecl *DCN = dyn_cast<NamedDecl>(DC))
-    Visit(DCN);
-  Out << "@T@";
-  Out << D->getName();
-}
-
-void USRGenerator::VisitTemplateTypeParmDecl(const TemplateTypeParmDecl *D) {
-  GenLoc(D);
-  return;
-}
-
-bool USRGenerator::GenLoc(const Decl *D) {
-  if (generatedLoc)
-    return IgnoreResults;
-  generatedLoc = true;
-  
-  // Guard against null declarations in invalid code.
-  if (!D) {
-    IgnoreResults = true;
-    return true;
-  }
-
-  // Use the location of canonical decl.
-  D = D->getCanonicalDecl();
-
-  const SourceManager &SM = Context->getSourceManager();
-  SourceLocation L = D->getLocStart();
-  if (L.isInvalid()) {
-    IgnoreResults = true;
-    return true;
-  }
-  L = SM.getExpansionLoc(L);
-  const std::pair<FileID, unsigned> &Decomposed = SM.getDecomposedLoc(L);
-  const FileEntry *FE = SM.getFileEntryForID(Decomposed.first);
-  if (FE) {
-    Out << llvm::sys::path::filename(FE->getName());
-  }
-  else {
-    // This case really isn't interesting.
-    IgnoreResults = true;
-    return true;
-  }
-  // Use the offest into the FileID to represent the location.  Using
-  // a line/column can cause us to look back at the original source file,
-  // which is expensive.
-  Out << '@' << Decomposed.second;
-  return IgnoreResults;
-}
-
-void USRGenerator::VisitType(QualType T) {
-  // This method mangles in USR information for types.  It can possibly
-  // just reuse the naming-mangling logic used by codegen, although the
-  // requirements for USRs might not be the same.
-  ASTContext &Ctx = *Context;
-
-  do {
-    T = Ctx.getCanonicalType(T);
-    Qualifiers Q = T.getQualifiers();
-    unsigned qVal = 0;
-    if (Q.hasConst())
-      qVal |= 0x1;
-    if (Q.hasVolatile())
-      qVal |= 0x2;
-    if (Q.hasRestrict())
-      qVal |= 0x4;
-    if(qVal)
-      Out << ((char) ('0' + qVal));
-
-    // Mangle in ObjC GC qualifiers?
-
-    if (const PackExpansionType *Expansion = T->getAs<PackExpansionType>()) {
-      Out << 'P';
-      T = Expansion->getPattern();
-    }
-    
-    if (const BuiltinType *BT = T->getAs<BuiltinType>()) {
-      unsigned char c = '\0';
-      switch (BT->getKind()) {
-        case BuiltinType::Void:
-          c = 'v'; break;
-        case BuiltinType::Bool:
-          c = 'b'; break;
-        case BuiltinType::Char_U:
-        case BuiltinType::UChar:
-          c = 'c'; break;
-        case BuiltinType::Char16:
-          c = 'q'; break;
-        case BuiltinType::Char32:
-          c = 'w'; break;
-        case BuiltinType::UShort:
-          c = 's'; break;
-        case BuiltinType::UInt:
-          c = 'i'; break;
-        case BuiltinType::ULong:
-          c = 'l'; break;
-        case BuiltinType::ULongLong:
-          c = 'k'; break;
-        case BuiltinType::UInt128:
-          c = 'j'; break;
-        case BuiltinType::Char_S:
-        case BuiltinType::SChar:
-          c = 'C'; break;
-        case BuiltinType::WChar_S:
-        case BuiltinType::WChar_U:
-          c = 'W'; break;
-        case BuiltinType::Short:
-          c = 'S'; break;
-        case BuiltinType::Int:
-          c = 'I'; break;
-        case BuiltinType::Long:
-          c = 'L'; break;
-        case BuiltinType::LongLong:
-          c = 'K'; break;
-        case BuiltinType::Int128:
-          c = 'J'; break;
-        case BuiltinType::Half:
-          c = 'h'; break;
-        case BuiltinType::Float:
-          c = 'f'; break;
-        case BuiltinType::Double:
-          c = 'd'; break;
-        case BuiltinType::LongDouble:
-          c = 'D'; break;
-        case BuiltinType::NullPtr:
-          c = 'n'; break;
-#define BUILTIN_TYPE(Id, SingletonId)
-#define PLACEHOLDER_TYPE(Id, SingletonId) case BuiltinType::Id:
-#include "clang/AST/BuiltinTypes.def"
-        case BuiltinType::Dependent:
-        case BuiltinType::OCLImage1d:
-        case BuiltinType::OCLImage1dArray:
-        case BuiltinType::OCLImage1dBuffer:
-        case BuiltinType::OCLImage2d:
-        case BuiltinType::OCLImage2dArray:
-        case BuiltinType::OCLImage3d:
-        case BuiltinType::OCLEvent:
-        case BuiltinType::OCLSampler:
-          IgnoreResults = true;
-          return;
-        case BuiltinType::ObjCId:
-          c = 'o'; break;
-        case BuiltinType::ObjCClass:
-          c = 'O'; break;
-        case BuiltinType::ObjCSel:
-          c = 'e'; break;
-      }
-      Out << c;
-      return;
-    }
-
-    // If we have already seen this (non-built-in) type, use a substitution
-    // encoding.
-    llvm::DenseMap<const Type *, unsigned>::iterator Substitution
-      = TypeSubstitutions.find(T.getTypePtr());
-    if (Substitution != TypeSubstitutions.end()) {
-      Out << 'S' << Substitution->second << '_';
-      return;
-    } else {
-      // Record this as a substitution.
-      unsigned Number = TypeSubstitutions.size();
-      TypeSubstitutions[T.getTypePtr()] = Number;
-    }
-    
-    if (const PointerType *PT = T->getAs<PointerType>()) {
-      Out << '*';
-      T = PT->getPointeeType();
-      continue;
-    }
-    if (const ReferenceType *RT = T->getAs<ReferenceType>()) {
-      Out << '&';
-      T = RT->getPointeeType();
-      continue;
-    }
-    if (const FunctionProtoType *FT = T->getAs<FunctionProtoType>()) {
-      Out << 'F';
-      VisitType(FT->getResultType());
-      for (FunctionProtoType::arg_type_iterator
-            I = FT->arg_type_begin(), E = FT->arg_type_end(); I!=E; ++I) {
-        VisitType(*I);
-      }
-      if (FT->isVariadic())
-        Out << '.';
-      return;
-    }
-    if (const BlockPointerType *BT = T->getAs<BlockPointerType>()) {
-      Out << 'B';
-      T = BT->getPointeeType();
-      continue;
-    }
-    if (const ComplexType *CT = T->getAs<ComplexType>()) {
-      Out << '<';
-      T = CT->getElementType();
-      continue;
-    }
-    if (const TagType *TT = T->getAs<TagType>()) {
-      Out << '$';
-      VisitTagDecl(TT->getDecl());
-      return;
-    }
-    if (const TemplateTypeParmType *TTP = T->getAs<TemplateTypeParmType>()) {
-      Out << 't' << TTP->getDepth() << '.' << TTP->getIndex();
-      return;
-    }
-    if (const TemplateSpecializationType *Spec
-                                    = T->getAs<TemplateSpecializationType>()) {
-      Out << '>';
-      VisitTemplateName(Spec->getTemplateName());
-      Out << Spec->getNumArgs();
-      for (unsigned I = 0, N = Spec->getNumArgs(); I != N; ++I)
-        VisitTemplateArgument(Spec->getArg(I));
-      return;
-    }
-    
-    // Unhandled type.
-    Out << ' ';
-    break;
-  } while (true);
-}
-
-void USRGenerator::VisitTemplateParameterList(
-                                         const TemplateParameterList *Params) {
-  if (!Params)
-    return;
-  Out << '>' << Params->size();
-  for (TemplateParameterList::const_iterator P = Params->begin(),
-                                          PEnd = Params->end();
-       P != PEnd; ++P) {
-    Out << '#';
-    if (isa<TemplateTypeParmDecl>(*P)) {
-      if (cast<TemplateTypeParmDecl>(*P)->isParameterPack())
-        Out<< 'p';
-      Out << 'T';
-      continue;
-    }
-    
-    if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(*P)) {
-      if (NTTP->isParameterPack())
-        Out << 'p';
-      Out << 'N';
-      VisitType(NTTP->getType());
-      continue;
-    }
-    
-    TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(*P);
-    if (TTP->isParameterPack())
-      Out << 'p';
-    Out << 't';
-    VisitTemplateParameterList(TTP->getTemplateParameters());
-  }
-}
-
-void USRGenerator::VisitTemplateName(TemplateName Name) {
-  if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
-    if (TemplateTemplateParmDecl *TTP
-                              = dyn_cast<TemplateTemplateParmDecl>(Template)) {
-      Out << 't' << TTP->getDepth() << '.' << TTP->getIndex();
-      return;
-    }
-    
-    Visit(Template);
-    return;
-  }
-  
-  // FIXME: Visit dependent template names.
-}
-
-void USRGenerator::VisitTemplateArgument(const TemplateArgument &Arg) {
-  switch (Arg.getKind()) {
-  case TemplateArgument::Null:
-    break;
-
-  case TemplateArgument::Declaration:
-    Visit(Arg.getAsDecl());
-    break;
-
-  case TemplateArgument::NullPtr:
-    break;
-
-  case TemplateArgument::TemplateExpansion:
-    Out << 'P'; // pack expansion of...
-    // Fall through
-  case TemplateArgument::Template:
-    VisitTemplateName(Arg.getAsTemplateOrTemplatePattern());
-    break;
-      
-  case TemplateArgument::Expression:
-    // FIXME: Visit expressions.
-    break;
-      
-  case TemplateArgument::Pack:
-    Out << 'p' << Arg.pack_size();
-    for (TemplateArgument::pack_iterator P = Arg.pack_begin(), PEnd = Arg.pack_end();
-         P != PEnd; ++P)
-      VisitTemplateArgument(*P);
-    break;
-      
-  case TemplateArgument::Type:
-    VisitType(Arg.getAsType());
-    break;
-      
-  case TemplateArgument::Integral:
-    Out << 'V';
-    VisitType(Arg.getIntegralType());
-    Out << Arg.getAsIntegral();
-    break;
-  }
-}
-
-//===----------------------------------------------------------------------===//
-// General purpose USR generation methods.
-//===----------------------------------------------------------------------===//
-
-void USRGenerator::GenObjCClass(StringRef cls) {
-  Out << "objc(cs)" << cls;
-}
-
-void USRGenerator::GenObjCCategory(StringRef cls, StringRef cat) {
-  Out << "objc(cy)" << cls << '@' << cat;
-}
-
-void USRGenerator::GenObjCIvar(StringRef ivar) {
-  Out << '@' << ivar;
-}
-
-void USRGenerator::GenObjCMethod(StringRef meth, bool isInstanceMethod) {
-  Out << (isInstanceMethod ? "(im)" : "(cm)") << meth;
-}
-
-void USRGenerator::GenObjCProperty(StringRef prop) {
-  Out << "(py)" << prop;
-}
-
-void USRGenerator::GenObjCProtocol(StringRef prot) {
-  Out << "objc(pl)" << prot;
-}
+using namespace clang::index;
 
 //===----------------------------------------------------------------------===//
 // API hooks.
@@ -805,17 +31,7 @@ static inline StringRef extractUSRSuffix(StringRef s) {
 }
 
 bool cxcursor::getDeclCursorUSR(const Decl *D, SmallVectorImpl<char> &Buf) {
-  // Don't generate USRs for things with invalid locations.
-  if (!D || D->getLocStart().isInvalid())
-    return true;
-
-  USRGenerator UG(&D->getASTContext(), &Buf);
-  UG->Visit(D);
-
-  if (UG->ignoreResults())
-    return true;
-
-  return false;
+  return generateUSRForDecl(D, Buf);
 }
 
 extern "C" {
@@ -857,12 +73,10 @@ CXString clang_getCursorUSR(CXCursor C) {
     if (!buf)
       return cxstring::createEmpty();
 
-    {
-      USRGenerator UG(&cxcursor::getCursorASTUnit(C)->getASTContext(),
-                      &buf->Data);
-      UG << "macro@"
-        << cxcursor::getCursorMacroDefinition(C)->getName()->getNameStart();
-    }
+    buf->Data += getUSRSpacePrefix();
+    buf->Data += "macro@";
+    buf->Data +=
+        cxcursor::getCursorMacroDefinition(C)->getName()->getNameStart();
     buf->Data.push_back('\0');
     return createCXString(buf);
   }
@@ -871,46 +85,52 @@ CXString clang_getCursorUSR(CXCursor C) {
 }
 
 CXString clang_constructUSR_ObjCIvar(const char *name, CXString classUSR) {
-  USRGenerator UG;
-  UG << extractUSRSuffix(clang_getCString(classUSR));
-  UG->GenObjCIvar(name);
-  return cxstring::createDup(UG.str());
+  SmallString<128> Buf(getUSRSpacePrefix());
+  llvm::raw_svector_ostream OS(Buf);
+  OS << extractUSRSuffix(clang_getCString(classUSR));
+  generateUSRForObjCIvar(name, OS);
+  return cxstring::createDup(OS.str());
 }
 
 CXString clang_constructUSR_ObjCMethod(const char *name,
                                        unsigned isInstanceMethod,
                                        CXString classUSR) {
-  USRGenerator UG;
-  UG << extractUSRSuffix(clang_getCString(classUSR));
-  UG->GenObjCMethod(name, isInstanceMethod);
-  return cxstring::createDup(UG.str());
+  SmallString<128> Buf(getUSRSpacePrefix());
+  llvm::raw_svector_ostream OS(Buf);
+  OS << extractUSRSuffix(clang_getCString(classUSR));
+  generateUSRForObjCMethod(name, isInstanceMethod, OS);
+  return cxstring::createDup(OS.str());
 }
 
 CXString clang_constructUSR_ObjCClass(const char *name) {
-  USRGenerator UG;
-  UG->GenObjCClass(name);
-  return cxstring::createDup(UG.str());
+  SmallString<128> Buf(getUSRSpacePrefix());
+  llvm::raw_svector_ostream OS(Buf);
+  generateUSRForObjCClass(name, OS);
+  return cxstring::createDup(OS.str());
 }
 
 CXString clang_constructUSR_ObjCProtocol(const char *name) {
-  USRGenerator UG;
-  UG->GenObjCProtocol(name);
-  return cxstring::createDup(UG.str());
+  SmallString<128> Buf(getUSRSpacePrefix());
+  llvm::raw_svector_ostream OS(Buf);
+  generateUSRForObjCProtocol(name, OS);
+  return cxstring::createDup(OS.str());
 }
 
 CXString clang_constructUSR_ObjCCategory(const char *class_name,
                                          const char *category_name) {
-  USRGenerator UG;
-  UG->GenObjCCategory(class_name, category_name);
-  return cxstring::createDup(UG.str());
+  SmallString<128> Buf(getUSRSpacePrefix());
+  llvm::raw_svector_ostream OS(Buf);
+  generateUSRForObjCCategory(class_name, category_name, OS);
+  return cxstring::createDup(OS.str());
 }
 
 CXString clang_constructUSR_ObjCProperty(const char *property,
                                          CXString classUSR) {
-  USRGenerator UG;
-  UG << extractUSRSuffix(clang_getCString(classUSR));
-  UG->GenObjCProperty(property);
-  return cxstring::createDup(UG.str());
+  SmallString<128> Buf(getUSRSpacePrefix());
+  llvm::raw_svector_ostream OS(Buf);
+  OS << extractUSRSuffix(clang_getCString(classUSR));
+  generateUSRForObjCProperty(property, OS);
+  return cxstring::createDup(OS.str());
 }
 
 } // end extern "C"