Refactor and simplify the CodeCompleteConsumer, so that all of the

real work is performed within Sema. Addresses Chris's comments, but
still retains the heavyweight list-of-multimaps data structure.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@82459 91177308-0d34-0410-b5e6-96231b3b80d8

6 files changed, 945 insertions, 1079 deletions

diff --git a/include/clang/Sema/CodeCompleteConsumer.h b/include/clang/Sema/CodeCompleteConsumer.h
index a8facd8fdc..3a7e73706b 100644
--- a/include/clang/Sema/CodeCompleteConsumer.h
+++ b/include/clang/Sema/CodeCompleteConsumer.h
@@ -13,15 +13,9 @@
 #ifndef LLVM_CLANG_SEMA_CODECOMPLETECONSUMER_H
 #define LLVM_CLANG_SEMA_CODECOMPLETECONSUMER_H
 
-#include "clang/AST/DeclarationName.h"
-#include "clang/AST/Type.h"
-#include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallVector.h"
-#include <list>
-#include <map>
 #include <memory>
 #include <string>
-#include <vector>
 
 namespace llvm {
 class raw_ostream;
@@ -29,10 +23,7 @@ class raw_ostream;
 
 namespace clang {
   
-class Decl;
-class DeclContext;
 class NamedDecl;
-class Scope;
 class Sema;
 
 /// \brief A "string" used to describe how code completion can
@@ -90,8 +81,8 @@ public:
 
     /// \brief Create a new placeholder chunk.
     static Chunk CreatePlaceholder(const char *Placeholder);
-
-    /// \brief Destroy this chunk.
+    
+    /// \brief Destroy this chunk, deallocating any memory it owns.
     void Destroy();
   };
   
@@ -135,10 +126,6 @@ public:
 /// \brief Abstract interface for a consumer of code-completion 
 /// information.
 class CodeCompleteConsumer {
-  /// \brief The semantic-analysis object to which this code-completion
-  /// consumer is attached.
-  Sema &SemaRef;
-  
 public:
   /// \brief Captures a result of code completion.
   struct Result {
@@ -176,209 +163,38 @@ public:
     /// \brief Build a result that refers to a keyword or symbol.
     Result(const char *Keyword, unsigned Rank)
       : Kind(RK_Keyword), Keyword(Keyword), Rank(Rank), Hidden(false) { }
-  };
-    
-  /// \brief A container of code-completion results.
-  class ResultSet {
-  public:
-    /// \brief The type of a name-lookup filter, which can be provided to the
-    /// name-lookup routines to specify which declarations should be included in
-    /// the result set (when it returns true) and which declarations should be
-    /// filtered out (returns false).
-    typedef bool (CodeCompleteConsumer::*LookupFilter)(NamedDecl *) const;
-    
-  private:
-    /// \brief The actual results we have found.
-    std::vector<Result> Results;
-
-    /// \brief A record of all of the declarations we have found and placed
-    /// into the result set, used to ensure that no declaration ever gets into
-    /// the result set twice.
-    llvm::SmallPtrSet<Decl*, 16> AllDeclsFound;
-    
-    /// \brief A mapping from declaration names to the declarations that have
-    /// this name within a particular scope and their index within the list of
-    /// results.
-    typedef std::multimap<DeclarationName, 
-                          std::pair<NamedDecl *, unsigned> > ShadowMap;
-    
-    /// \brief The code-completion consumer that is producing these results.
-    CodeCompleteConsumer &Completer;
     
-    /// \brief If non-NULL, a filter function used to remove any code-completion
-    /// results that are not desirable.
-    LookupFilter Filter;
-    
-    /// \brief A list of shadow maps, which is used to model name hiding at
-    /// different levels of, e.g., the inheritance hierarchy.
-    std::list<ShadowMap> ShadowMaps;
-        
-  public:
-    explicit ResultSet(CodeCompleteConsumer &Completer,
-                       LookupFilter Filter = 0)
-      : Completer(Completer), Filter(Filter) { }
-    
-    /// \brief Set the filter used for code-completion results.
-    void setFilter(LookupFilter Filter) {
-      this->Filter = Filter;
-    }
-    
-    typedef std::vector<Result>::iterator iterator;
-    iterator begin() { return Results.begin(); }
-    iterator end() { return Results.end(); }
-    
-    Result *data() { return Results.empty()? 0 : &Results.front(); }
-    unsigned size() const { return Results.size(); }
-    bool empty() const { return Results.empty(); }
-        
-    /// \brief Add a new result to this result set (if it isn't already in one
-    /// of the shadow maps), or replace an existing result (for, e.g., a 
-    /// redeclaration).
-    void MaybeAddResult(Result R);
-    
-    /// \brief Enter into a new scope.
-    void EnterNewScope();
-    
-    /// \brief Exit from the current scope.
-    void ExitScope();
+    /// \brief Create a new code-completion string that describes how to insert
+    /// this result into a program.
+    CodeCompletionString *CreateCodeCompletionString(Sema &S);
   };
-  
-  /// \brief Create a new code-completion consumer and registers it with
-  /// the given semantic-analysis object.
-  explicit CodeCompleteConsumer(Sema &S);
-  
+    
   /// \brief Deregisters and destroys this code-completion consumer.
   virtual ~CodeCompleteConsumer();
-  
-  /// \brief Retrieve the semantic-analysis object to which this code-completion
-  /// consumer is attached.
-  Sema &getSema() const { return SemaRef; }
-  
+    
   /// \name Code-completion callbacks
   //@{
-  
   /// \brief Process the finalized code-completion results.
   virtual void ProcessCodeCompleteResults(Result *Results, 
                                           unsigned NumResults) { }
-  
-  /// \brief Code completion for a member access expression, e.g., "x->" or
-  /// "x.".
-  ///
-  /// \param S is the scope in which code-completion occurs.
-  ///
-  /// \param BaseType is the type whose members are being accessed.
-  ///
-  /// \param IsArrow whether this member referenced was written with an
-  /// arrow ("->") or a period (".").
-  virtual void CodeCompleteMemberReferenceExpr(Scope *S, QualType BaseType,
-                                               bool IsArrow);
-  
-  /// \brief Code completion for a tag name following an enum, class, struct,
-  /// or union keyword.
-  virtual void CodeCompleteTag(Scope *S, ElaboratedType::TagKind TK);
-  
-  /// \brief Code completion for a qualified-id, e.g., "std::"
-  ///
-  /// \param S the scope in which the nested-name-specifier occurs.
-  ///
-  /// \param NNS the nested-name-specifier before the code-completion location.
-  ///
-  /// \param EnteringContext whether the parser will be entering the scope of
-  /// the qualified-id.
-  virtual void CodeCompleteQualifiedId(Scope *S, NestedNameSpecifier *NNS,
-                                       bool EnteringContext);
-  
-  /// \brief Code completion for a C++ "using" declaration or directive.
-  ///
-  /// This code completion action is invoked when the code-completion token is
-  /// found after the "using" keyword.
-  ///
-  /// \param S the scope in which the "using" occurs.
-  virtual void CodeCompleteUsing(Scope *S);
-  
-  /// \brief Code completion for a C++ using directive.
-  ///
-  /// This code completion action is invoked when the code-completion token is
-  /// found after "using namespace".
-  ///
-  /// \param S the scope in which the "using namespace" occurs.
-  virtual void CodeCompleteUsingDirective(Scope *S);
-  
-  /// \brief Code completion for a C++ namespace declaration or namespace
-  /// alias declaration.
-  ///
-  /// This code completion action is invoked when the code-completion token is
-  /// found after "namespace".
-  ///
-  /// \param S the scope in which the "namespace" token occurs.
-  virtual void CodeCompleteNamespaceDecl(Scope *S);
-  
-  /// \brief Code completion for a C++ namespace alias declaration.
-  ///
-  /// This code completion action is invoked when the code-completion token is
-  /// found after "namespace identifier = ".
-  ///
-  /// \param S the scope in which the namespace alias declaration occurs.
-  virtual void CodeCompleteNamespaceAliasDecl(Scope *S);
-  
-  /// \brief Code completion for an operator name.
-  ///
-  /// This code completion action is invoked when the code-completion token is
-  /// found after the keyword "operator".
-  ///
-  /// \param S the scope in which the operator keyword occurs.
-  virtual void CodeCompleteOperatorName(Scope *S);
-  //@}
-  
-  /// \name Name lookup functions
-  ///
-  /// The name lookup functions in this group collect code-completion results
-  /// by performing a form of name looking into a scope or declaration context.
-  //@{
-  unsigned CollectLookupResults(Scope *S, unsigned InitialRank,
-                                ResultSet &Results);
-  unsigned CollectMemberLookupResults(DeclContext *Ctx, unsigned InitialRank, 
-                                      ResultSet &Results);
-  unsigned CollectMemberLookupResults(DeclContext *Ctx, unsigned InitialRank, 
-                               llvm::SmallPtrSet<DeclContext *, 16> &Visited,
-                                      ResultSet &Results);
-  //@}
-  
-  /// \name Name lookup predicates
-  ///
-  /// These predicates can be passed to the name lookup functions to filter the
-  /// results of name lookup. All of the predicates have the same type, so that
-  /// 
-  //@{
-  bool IsNestedNameSpecifier(NamedDecl *ND) const;
-  bool IsEnum(NamedDecl *ND) const;
-  bool IsClassOrStruct(NamedDecl *ND) const;
-  bool IsUnion(NamedDecl *ND) const;
-  bool IsNamespace(NamedDecl *ND) const;
-  bool IsNamespaceOrAlias(NamedDecl *ND) const;
-  bool IsType(NamedDecl *ND) const;
-  //@}
-  
-  /// \name Utility functions
-  ///
-  //@{  
-  bool canHiddenResultBeFound(NamedDecl *Hidden, NamedDecl *Visible);
-  void AddTypeSpecifierResults(unsigned Rank, ResultSet &Results);
-  CodeCompletionString *CreateCodeCompletionString(Result R);
   //@}
 };
   
 /// \brief A simple code-completion consumer that prints the results it 
 /// receives in a simple format.
 class PrintingCodeCompleteConsumer : public CodeCompleteConsumer {
+  /// \brief The semantic-analysis object to which this code-completion
+  /// consumer is attached.
+  Sema &SemaRef;
+  
   /// \brief The raw output stream.
   llvm::raw_ostream &OS;
-  
+    
 public:
   /// \brief Create a new printing code-completion consumer that prints its
   /// results to the given raw output stream.
   PrintingCodeCompleteConsumer(Sema &S, llvm::raw_ostream &OS)
-    : CodeCompleteConsumer(S), OS(OS) { }
+    : SemaRef(S), OS(OS) { }
   
   /// \brief Prints the finalized code-completion results.
   virtual void ProcessCodeCompleteResults(Result *Results, 
diff --git a/lib/Lex/Lexer.cpp b/lib/Lex/Lexer.cpp
index 351b63f6bb..74ac55cf2e 100644
--- a/lib/Lex/Lexer.cpp
+++ b/lib/Lex/Lexer.cpp
@@ -1309,6 +1309,18 @@ bool Lexer::LexEndOfFile(Token &Result, const char *CurPtr) {
     SetCommentRetentionState(PP->getCommentRetentionState());
     return true;  // Have a token.
   }
+ 
+  // If we are in raw mode, return this event as an EOF token.  Let the caller
+  // that put us in raw mode handle the event.
+  if (isLexingRawMode()) {
+    Result.startToken();
+    BufferPtr = BufferEnd;
+    FormTokenWithChars(Result, BufferEnd, tok::eof);
+    return true;
+  }
+
+  // Otherwise, check if we are code-completing, then issue diagnostics for 
+  // unterminated #if and missing newline.
 
   if (IsEofCodeCompletion) {
     // We're at the end of the file, but we've been asked to conside the
@@ -1316,23 +1328,12 @@ bool Lexer::LexEndOfFile(Token &Result, const char *CurPtr) {
     // code-completion token.
     Result.startToken();
     FormTokenWithChars(Result, CurPtr, tok::code_completion);
-
+    
     // Only do the eof -> code_completion translation once.
     IsEofCodeCompletion = false;
     return true;
   }
   
-  // If we are in raw mode, return this event as an EOF token.  Let the caller
-  // that put us in raw mode handle the event.
-  if (isLexingRawMode()) {
-    Result.startToken();
-    BufferPtr = BufferEnd;
-    FormTokenWithChars(Result, BufferEnd, tok::eof);
-    return true;
-  }
-
-  // Otherwise, issue diagnostics for unterminated #if and missing newline.
-
   // If we are in a #if directive, emit an error.
   while (!ConditionalStack.empty()) {
     PP->Diag(ConditionalStack.back().IfLoc,
diff --git a/lib/Sema/CodeCompleteConsumer.cpp b/lib/Sema/CodeCompleteConsumer.cpp
index 2e3d5cd88e..1e505090fb 100644
--- a/lib/Sema/CodeCompleteConsumer.cpp
+++ b/lib/Sema/CodeCompleteConsumer.cpp
@@ -1,4 +1,4 @@
-//===---- CodeCompleteConsumer.h - Code Completion Interface ----*- C++ -*-===//
+//===--- CodeCompleteConsumer.cpp - Code Completion Interface ---*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -88,853 +88,11 @@ std::string CodeCompletionString::getAsString() const {
 // Code completion consumer implementation
 //===----------------------------------------------------------------------===//
 
-CodeCompleteConsumer::CodeCompleteConsumer(Sema &S) : SemaRef(S) {
-  SemaRef.setCodeCompleteConsumer(this);
-}
-
-CodeCompleteConsumer::~CodeCompleteConsumer() {
-  SemaRef.setCodeCompleteConsumer(0);
-}
-
-void 
-CodeCompleteConsumer::CodeCompleteMemberReferenceExpr(Scope *S, 
-                                                      QualType BaseType,
-                                                      bool IsArrow) {
-  if (IsArrow) {
-    if (const PointerType *Ptr = BaseType->getAs<PointerType>())
-      BaseType = Ptr->getPointeeType();
-    else if (BaseType->isObjCObjectPointerType())
-    /*Do nothing*/ ;
-    else
-      return;
-  }
-  
-  ResultSet Results(*this);
-  unsigned NextRank = 0;
-  
-  if (const RecordType *Record = BaseType->getAs<RecordType>()) {
-    NextRank = CollectMemberLookupResults(Record->getDecl(), NextRank, Results);
-
-    if (getSema().getLangOptions().CPlusPlus) {
-      if (!Results.empty()) {
-        // The "template" keyword can follow "->" or "." in the grammar.
-        // However, we only want to suggest the template keyword if something
-        // is dependent.
-        bool IsDependent = BaseType->isDependentType();
-        if (!IsDependent) {
-          for (Scope *DepScope = S; DepScope; DepScope = DepScope->getParent())
-            if (DeclContext *Ctx = (DeclContext *)DepScope->getEntity()) {
-              IsDependent = Ctx->isDependentContext();
-              break;
-            }
-        }
-        
-        if (IsDependent)
-          Results.MaybeAddResult(Result("template", NextRank++));
-      }
-
-      // We could have the start of a nested-name-specifier. Add those
-      // results as well.
-      Results.setFilter(&CodeCompleteConsumer::IsNestedNameSpecifier);
-      CollectLookupResults(S, NextRank, Results);
-    }
-
-    // Hand off the results found for code completion.
-    ProcessCodeCompleteResults(Results.data(), Results.size());
-    
-    // We're done!
-    return;
-  }
-}
-
-void CodeCompleteConsumer::CodeCompleteTag(Scope *S, ElaboratedType::TagKind TK) {
-  ResultSet::LookupFilter Filter = 0;
-  switch (TK) {
-  case ElaboratedType::TK_enum:
-    Filter = &CodeCompleteConsumer::IsEnum;
-    break;
-    
-  case ElaboratedType::TK_class:
-  case ElaboratedType::TK_struct:
-    Filter = &CodeCompleteConsumer::IsClassOrStruct;
-    break;
-    
-  case ElaboratedType::TK_union:
-    Filter = &CodeCompleteConsumer::IsUnion;
-    break;
-  }
-  
-  ResultSet Results(*this, Filter);
-  unsigned NextRank = CollectLookupResults(S, 0, Results);
-  
-  if (getSema().getLangOptions().CPlusPlus) {
-    // We could have the start of a nested-name-specifier. Add those
-    // results as well.
-    Results.setFilter(&CodeCompleteConsumer::IsNestedNameSpecifier);
-    CollectLookupResults(S, NextRank, Results);
-  }
-  
-  ProcessCodeCompleteResults(Results.data(), Results.size());
-}
-
-void 
-CodeCompleteConsumer::CodeCompleteQualifiedId(Scope *S, 
-                                              NestedNameSpecifier *NNS,
-                                              bool EnteringContext) {
-  CXXScopeSpec SS;
-  SS.setScopeRep(NNS);
-  DeclContext *Ctx = getSema().computeDeclContext(SS, EnteringContext);
-  if (!Ctx)
-    return;
-  
-  ResultSet Results(*this);
-  unsigned NextRank = CollectMemberLookupResults(Ctx, 0, Results);
-  
-  // The "template" keyword can follow "::" in the grammar, but only
-  // put it into the grammar if the nested-name-specifier is dependent.
-  if (!Results.empty() && NNS->isDependent())
-    Results.MaybeAddResult(Result("template", NextRank));
-  
-  ProcessCodeCompleteResults(Results.data(), Results.size());
-}
-
-void CodeCompleteConsumer::CodeCompleteUsing(Scope *S) { 
-  ResultSet Results(*this, &CodeCompleteConsumer::IsNestedNameSpecifier);
-  
-  // If we aren't in class scope, we could see the "namespace" keyword.
-  if (!S->isClassScope())
-    Results.MaybeAddResult(Result("namespace", 0));
-    
-  // After "using", we can see anything that would start a 
-  // nested-name-specifier.
-  CollectLookupResults(S, 0, Results);
-  
-  ProcessCodeCompleteResults(Results.data(), Results.size());
-}
-
-void CodeCompleteConsumer::CodeCompleteUsingDirective(Scope *S) { 
-  // After "using namespace", we expect to see a namespace name or namespace
-  // alias.
-  ResultSet Results(*this, &CodeCompleteConsumer::IsNamespaceOrAlias);
-  CollectLookupResults(S, 0, Results);
-  ProcessCodeCompleteResults(Results.data(), Results.size());  
-}
-
-void CodeCompleteConsumer::CodeCompleteNamespaceDecl(Scope *S) { 
-  ResultSet Results(*this, &CodeCompleteConsumer::IsNamespace);
-  DeclContext *Ctx = (DeclContext *)S->getEntity();
-  if (!S->getParent())
-    Ctx = getSema().Context.getTranslationUnitDecl();
-
-  if (Ctx && Ctx->isFileContext()) {
-    // We only want to see those namespaces that have already been defined
-    // within this scope, because its likely that the user is creating an
-    // extended namespace declaration. Keep track of the most recent 
-    // definition of each namespace.
-    std::map<NamespaceDecl *, NamespaceDecl *> OrigToLatest;
-    for (DeclContext::specific_decl_iterator<NamespaceDecl> 
-           NS(Ctx->decls_begin()), NSEnd(Ctx->decls_end());
-         NS != NSEnd; ++NS)
-      OrigToLatest[NS->getOriginalNamespace()] = *NS;
-
-    // Add the most recent definition (or extended definition) of each 
-    // namespace to the list of results.
-    for (std::map<NamespaceDecl *, NamespaceDecl *>::iterator 
-          NS = OrigToLatest.begin(), NSEnd = OrigToLatest.end();
-         NS != NSEnd; ++NS)
-      Results.MaybeAddResult(Result(NS->second, 0));
-  }
-  
-  ProcessCodeCompleteResults(Results.data(), Results.size());  
-}
-
-void CodeCompleteConsumer::CodeCompleteNamespaceAliasDecl(Scope *S) { 
-  // After "namespace", we expect to see a namespace  or alias.
-  ResultSet Results(*this, &CodeCompleteConsumer::IsNamespaceOrAlias);
-  CollectLookupResults(S, 0, Results);
-  ProcessCodeCompleteResults(Results.data(), Results.size());  
-}
-
-void CodeCompleteConsumer::CodeCompleteOperatorName(Scope *S) {
-  ResultSet Results(*this, &CodeCompleteConsumer::IsType);
-  
-  // Add the names of overloadable operators.
-#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly)      \
-  if (std::strcmp(Spelling, "?"))                                                  \
-    Results.MaybeAddResult(Result(Spelling, 0));
-#include "clang/Basic/OperatorKinds.def"
-  
-  // Add any type names visible from the current scope
-  unsigned NextRank = CollectLookupResults(S, 0, Results);
-  
-  // Add any type specifiers
-  AddTypeSpecifierResults(0, Results);
-  
-  // Add any nested-name-specifiers
-  Results.setFilter(&CodeCompleteConsumer::IsNestedNameSpecifier);
-  CollectLookupResults(S, NextRank + 1, Results);
-
-  ProcessCodeCompleteResults(Results.data(), Results.size());  
-}
-
-void CodeCompleteConsumer::ResultSet::MaybeAddResult(Result R) {
-  if (R.Kind != Result::RK_Declaration) {
-    // For non-declaration results, just add the result.
-    Results.push_back(R);
-    return;
-  }
-
-  // Look through using declarations.
-  if (UsingDecl *Using = dyn_cast<UsingDecl>(R.Declaration))
-    return MaybeAddResult(Result(Using->getTargetDecl(), R.Rank));
-  
-  // Handle each declaration in an overload set separately.
-  if (OverloadedFunctionDecl *Ovl 
-        = dyn_cast<OverloadedFunctionDecl>(R.Declaration)) {
-    for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(),
-                                                FEnd = Ovl->function_end();
-         F != FEnd; ++F)
-      MaybeAddResult(Result(*F, R.Rank));
-    
-    return;
-  }
-  
-  Decl *CanonDecl = R.Declaration->getCanonicalDecl();
-  unsigned IDNS = CanonDecl->getIdentifierNamespace();
-
-  // Friend declarations and declarations introduced due to friends are never
-  // added as results.
-  if (isa<FriendDecl>(CanonDecl) || 
-      (IDNS & (Decl::IDNS_OrdinaryFriend | Decl::IDNS_TagFriend)))
-    return;
-
-  if (const IdentifierInfo *Id = R.Declaration->getIdentifier()) {
-    // __va_list_tag is a freak of nature. Find it and skip it.
-    if (Id->isStr("__va_list_tag") || Id->isStr("__builtin_va_list"))
-      return;
-
-    // FIXME: Should we filter out other names in the implementation's
-    // namespace, e.g., those containing a __ or that start with _[A-Z]?
-  }
-
-  // C++ constructors are never found by name lookup.
-  if (isa<CXXConstructorDecl>(CanonDecl))
-    return;
-  
-  // Filter out any unwanted results.
-  if (Filter && !(Completer.*Filter)(R.Declaration))
-    return;
-  
-  ShadowMap &SMap = ShadowMaps.back();
-  ShadowMap::iterator I, IEnd;
-  for (llvm::tie(I, IEnd) = SMap.equal_range(R.Declaration->getDeclName());
-       I != IEnd; ++I) {
-    NamedDecl *ND = I->second.first;
-    unsigned Index = I->second.second;
-    if (ND->getCanonicalDecl() == CanonDecl) {
-      // This is a redeclaration. Always pick the newer declaration.
-      I->second.first = R.Declaration;
-      Results[Index].Declaration = R.Declaration;
-      
-      // Pick the best rank of the two.
-      Results[Index].Rank = std::min(Results[Index].Rank, R.Rank);
-      
-      // We're done.
-      return;
-    }
-  }
-  
-  // This is a new declaration in this scope. However, check whether this
-  // declaration name is hidden by a similarly-named declaration in an outer
-  // scope.
-  std::list<ShadowMap>::iterator SM, SMEnd = ShadowMaps.end();
-  --SMEnd;
-  for (SM = ShadowMaps.begin(); SM != SMEnd; ++SM) {
-    for (llvm::tie(I, IEnd) = SM->equal_range(R.Declaration->getDeclName());
-         I != IEnd; ++I) {
-      // A tag declaration does not hide a non-tag declaration.
-      if (I->second.first->getIdentifierNamespace() == Decl::IDNS_Tag &&
-          (IDNS & (Decl::IDNS_Member | Decl::IDNS_Ordinary | 
-                   Decl::IDNS_ObjCProtocol)))
-        continue;
-      
-      // Protocols are in distinct namespaces from everything else.
-      if (((I->second.first->getIdentifierNamespace() & Decl::IDNS_ObjCProtocol)
-           || (IDNS & Decl::IDNS_ObjCProtocol)) &&
-          I->second.first->getIdentifierNamespace() != IDNS)
-        continue;
-      
-      // The newly-added result is hidden by an entry in the shadow map.
-      if (Completer.canHiddenResultBeFound(R.Declaration, I->second.first)) {
-        // Note that this result was hidden.
-        R.Hidden = true;
-      } else {
-        // This result was hidden and cannot be found; don't bother adding
-        // it.
-        return;
-      }
-      
-      break;
-    }
-  }
-  
-  // Make sure that any given declaration only shows up in the result set once.
-  if (!AllDeclsFound.insert(CanonDecl))
-    return;
-  
-  // Insert this result into the set of results and into the current shadow
-  // map.
-  SMap.insert(std::make_pair(R.Declaration->getDeclName(),
-                             std::make_pair(R.Declaration, Results.size())));
-  Results.push_back(R);
-}
-
-/// \brief Enter into a new scope.
-void CodeCompleteConsumer::ResultSet::EnterNewScope() {
-  ShadowMaps.push_back(ShadowMap());
-}
-
-/// \brief Exit from the current scope.
-void CodeCompleteConsumer::ResultSet::ExitScope() {
-  ShadowMaps.pop_back();
-}
-
-// Find the next outer declaration context corresponding to this scope.
-static DeclContext *findOuterContext(Scope *S) {
-  for (S = S->getParent(); S; S = S->getParent())
-    if (S->getEntity())
-      return static_cast<DeclContext *>(S->getEntity())->getPrimaryContext();
-  
-  return 0;
-}
-
-/// \brief Collect the results of searching for declarations within the given
-/// scope and its parent scopes.
-///
-/// \param S the scope in which we will start looking for declarations.
-///
-/// \param InitialRank the initial rank given to results in this scope.
-/// Larger rank values will be used for results found in parent scopes.
-unsigned CodeCompleteConsumer::CollectLookupResults(Scope *S, 
-                                                    unsigned InitialRank,
-                                                    ResultSet &Results) {
-  if (!S)
-    return InitialRank;
-  
-  // FIXME: Using directives!
-  
-  unsigned NextRank = InitialRank;
-  Results.EnterNewScope();
-  if (S->getEntity() && 
-      !((DeclContext *)S->getEntity())->isFunctionOrMethod()) {
-    // Look into this scope's declaration context, along with any of its
-    // parent lookup contexts (e.g., enclosing classes), up to the point
-    // where we hit the context stored in the next outer scope.
-    DeclContext *Ctx = (DeclContext *)S->getEntity();
-    DeclContext *OuterCtx = findOuterContext(S);
-    
-    for (; Ctx && Ctx->getPrimaryContext() != OuterCtx;
-         Ctx = Ctx->getLookupParent()) {
-      if (Ctx->isFunctionOrMethod())
-        continue;
-      
-      NextRank = CollectMemberLookupResults(Ctx, NextRank + 1, Results);
-    }
-  } else if (!S->getParent()) {
-    // Look into the translation unit scope. We walk through the translation
-    // unit's declaration context, because the Scope itself won't have all of
-    // the declarations if 
-    NextRank = CollectMemberLookupResults(
-                                    getSema().Context.getTranslationUnitDecl(), 
-                                          NextRank + 1, Results);
-  } else {
-    // Walk through the declarations in this Scope.
-    for (Scope::decl_iterator D = S->decl_begin(), DEnd = S->decl_end();
-         D != DEnd; ++D) {
-      if (NamedDecl *ND = dyn_cast<NamedDecl>((Decl *)((*D).get())))
-        Results.MaybeAddResult(Result(ND, NextRank));        
-    }
-    
-    NextRank = NextRank + 1;
-  }
-  
-  // Lookup names in the parent scope.
-  NextRank = CollectLookupResults(S->getParent(), NextRank, Results);
-  Results.ExitScope();
-  
-  return NextRank;
-}
-
-/// \brief Collect the results of searching for members within the given
-/// declaration context.
-///
-/// \param Ctx the declaration context from which we will gather results.
-///
-/// \param InitialRank the initial rank given to results in this declaration
-/// context. Larger rank values will be used for, e.g., members found in
-/// base classes.
-///
-/// \param Results the result set that will be extended with any results
-/// found within this declaration context (and, for a C++ class, its bases).
-///
-/// \returns the next higher rank value, after considering all of the
-/// names within this declaration context.
-unsigned CodeCompleteConsumer::CollectMemberLookupResults(DeclContext *Ctx, 
-                                                          unsigned InitialRank, 
-                                                          ResultSet &Results) {
-  llvm::SmallPtrSet<DeclContext *, 16> Visited;
-  return CollectMemberLookupResults(Ctx, InitialRank, Visited, Results);
-}
-
-/// \brief Collect the results of searching for members within the given
-/// declaration context.
-///
-/// \param Ctx the declaration context from which we will gather results.
-///
-/// \param InitialRank the initial rank given to results in this declaration
-/// context. Larger rank values will be used for, e.g., members found in
-/// base classes.
-///
-/// \param Visited the set of declaration contexts that have already been
-/// visited. Declaration contexts will only be visited once.
-///
-/// \param Results the result set that will be extended with any results
-/// found within this declaration context (and, for a C++ class, its bases).
-///
-/// \returns the next higher rank value, after considering all of the
-/// names within this declaration context.
-unsigned CodeCompleteConsumer::CollectMemberLookupResults(DeclContext *Ctx, 
-                                                          unsigned InitialRank,
-                                 llvm::SmallPtrSet<DeclContext *, 16> &Visited,
-                                                          ResultSet &Results) {
-  // Make sure we don't visit the same context twice.
-  if (!Visited.insert(Ctx->getPrimaryContext()))
-    return InitialRank;
-  
-  // Enumerate all of the results in this context.
-  Results.EnterNewScope();
-  for (DeclContext *CurCtx = Ctx->getPrimaryContext(); CurCtx; 
-       CurCtx = CurCtx->getNextContext()) {
-    for (DeclContext::decl_iterator D = CurCtx->decls_begin(), 
-                                 DEnd = CurCtx->decls_end();
-         D != DEnd; ++D) {
-      if (NamedDecl *ND = dyn_cast<NamedDecl>(*D))
-        Results.MaybeAddResult(Result(ND, InitialRank));
-    }
-  }
-  
-  // Traverse the contexts of inherited classes.
-  unsigned NextRank = InitialRank;
-  if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) {
-    for (CXXRecordDecl::base_class_iterator B = Record->bases_begin(),
-                                         BEnd = Record->bases_end();
-         B != BEnd; ++B) {
-      QualType BaseType = B->getType();
-      
-      // Don't look into dependent bases, because name lookup can't look
-      // there anyway.
-      if (BaseType->isDependentType())
-        continue;
-      
-      const RecordType *Record = BaseType->getAs<RecordType>();
-      if (!Record)
-        continue;
-      
-      // FIXME: It would be nice to be able to determine whether referencing
-      // a particular member would be ambiguous. For example, given
-      //
-      //   struct A { int member; };
-      //   struct B { int member; };
-      //   struct C : A, B { };
-      //
-      //   void f(C *c) { c->### }
-      // accessing 'member' would result in an ambiguity. However, code
-      // completion could be smart enough to qualify the member with the
-      // base class, e.g.,
-      //
-      //   c->B::member
-      //
-      // or
-      //
-      //   c->A::member
-      
-      // Collect results from this base class (and its bases).
-      NextRank = std::max(NextRank, 
-                          CollectMemberLookupResults(Record->getDecl(), 
-                                                     InitialRank + 1,
-                                                     Visited,
-                                                     Results));
-    }
-  }
-  
-  // FIXME: Look into base classes in Objective-C!
-
-  Results.ExitScope();
-  return NextRank;
-}
-
-/// \brief Determines whether the given declaration is suitable as the 
-/// start of a C++ nested-name-specifier, e.g., a class or namespace.
-bool CodeCompleteConsumer::IsNestedNameSpecifier(NamedDecl *ND) const {
-  // Allow us to find class templates, too.
-  if (ClassTemplateDecl *ClassTemplate = dyn_cast<ClassTemplateDecl>(ND))
-    ND = ClassTemplate->getTemplatedDecl();
-  
-  return getSema().isAcceptableNestedNameSpecifier(ND);
-}
-
-/// \brief Determines whether the given declaration is an enumeration.
-bool CodeCompleteConsumer::IsEnum(NamedDecl *ND) const {
-  return isa<EnumDecl>(ND);
-}
-
-/// \brief Determines whether the given declaration is a class or struct.
-bool CodeCompleteConsumer::IsClassOrStruct(NamedDecl *ND) const {
-  // Allow us to find class templates, too.
-  if (ClassTemplateDecl *ClassTemplate = dyn_cast<ClassTemplateDecl>(ND))
-    ND = ClassTemplate->getTemplatedDecl();
-  
-  if (RecordDecl *RD = dyn_cast<RecordDecl>(ND))
-    return RD->getTagKind() == TagDecl::TK_class ||
-           RD->getTagKind() == TagDecl::TK_struct;
-  
-  return false;
-}
-
-/// \brief Determines whether the given declaration is a union.
-bool CodeCompleteConsumer::IsUnion(NamedDecl *ND) const {
-  // Allow us to find class templates, too.
-  if (ClassTemplateDecl *ClassTemplate = dyn_cast<ClassTemplateDecl>(ND))
-    ND = ClassTemplate->getTemplatedDecl();
-
-  if (RecordDecl *RD = dyn_cast<RecordDecl>(ND))
-    return RD->getTagKind() == TagDecl::TK_union;
-  
-  return false;
-}
-
-/// \brief Determines whether the given declaration is a namespace.
-bool CodeCompleteConsumer::IsNamespace(NamedDecl *ND) const {
-  return isa<NamespaceDecl>(ND);
-}
-
-/// \brief Determines whether the given declaration is a namespace or 
-/// namespace alias.
-bool CodeCompleteConsumer::IsNamespaceOrAlias(NamedDecl *ND) const {
-  return isa<NamespaceDecl>(ND) || isa<NamespaceAliasDecl>(ND);
-}
-
-/// \brief Brief determines whether the given declaration is a namespace or
-/// namespace alias.
-bool CodeCompleteConsumer::IsType(NamedDecl *ND) const {
-  return isa<TypeDecl>(ND);
-}
-
-namespace {
-  struct VISIBILITY_HIDDEN SortCodeCompleteResult {
-    typedef CodeCompleteConsumer::Result Result;
-    
-    bool operator()(const Result &X, const Result &Y) const {
-      // Sort first by rank.
-      if (X.Rank < Y.Rank)
-        return true;
-      else if (X.Rank > Y.Rank)
-        return false;
-      
-      // Result kinds are ordered by decreasing importance.
-      if (X.Kind < Y.Kind)
-        return true;
-      else if (X.Kind > Y.Kind)
-        return false;
-
-      // Non-hidden names precede hidden names.
-      if (X.Hidden != Y.Hidden)
-        return !X.Hidden;
-      
-      // Ordering depends on the kind of result.
-      switch (X.Kind) {
-      case Result::RK_Declaration:
-        // Order based on the declaration names.
-        return X.Declaration->getDeclName() < Y.Declaration->getDeclName();
-          
-      case Result::RK_Keyword:
-        return strcmp(X.Keyword, Y.Keyword) == -1;
-      }
-      
-      // If only our C++ compiler did control-flow warnings properly.
-      return false;
-    }
-  };
-}
-
-/// \brief Determines whether the given hidden result could be found with
-/// some extra work, e.g., by qualifying the name.
-///
-/// \param Hidden the declaration that is hidden by the currenly \p Visible
-/// declaration.
-///
-/// \param Visible the declaration with the same name that is already visible.
-///
-/// \returns true if the hidden result can be found by some mechanism,
-/// false otherwise.
-bool CodeCompleteConsumer::canHiddenResultBeFound(NamedDecl *Hidden, 
-                                                  NamedDecl *Visible) {
-  // In C, there is no way to refer to a hidden name.
-  if (!getSema().getLangOptions().CPlusPlus)
-    return false;
-  
-  DeclContext *HiddenCtx = Hidden->getDeclContext()->getLookupContext();
-  
-  // There is no way to qualify a name declared in a function or method.
-  if (HiddenCtx->isFunctionOrMethod())
-    return false;
-
-  // If the hidden and visible declarations are in