Allocate CodeCompletionString and all of its components in a

BumpPtrAllocator, rather than manually new/delete'ing them. This
optimization also allows us to avoid allocating memory for and copying
constant strings (e.g., "return", "class").

This also required embedding the priority and availability of results
within the code completion string, to avoid extra memory allocation
within libclang.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@124673 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 838 insertions, 884 deletions

diff --git a/lib/Frontend/ASTUnit.cpp b/lib/Frontend/ASTUnit.cpp
index 9116d0ed17..5617df6881 100644
--- a/lib/Frontend/ASTUnit.cpp
+++ b/lib/Frontend/ASTUnit.cpp
@@ -222,7 +222,7 @@ void ASTUnit::CacheCodeCompletionResults() {
   // Gather the set of global code completions.
   typedef CodeCompletionResult Result;
   llvm::SmallVector<Result, 8> Results;
-  TheSema->GatherGlobalCodeCompletions(Results);
+  TheSema->GatherGlobalCodeCompletions(CachedCompletionAllocator, Results);
   
   // Translate global code completions into cached completions.
   llvm::DenseMap<CanQualType, unsigned> CompletionTypes;
@@ -232,7 +232,8 @@ void ASTUnit::CacheCodeCompletionResults() {
     case Result::RK_Declaration: {
       bool IsNestedNameSpecifier = false;
       CachedCodeCompletionResult CachedResult;
-      CachedResult.Completion = Results[I].CreateCodeCompletionString(*TheSema);
+      CachedResult.Completion = Results[I].CreateCodeCompletionString(*TheSema,
+                                                     CachedCompletionAllocator);
       CachedResult.ShowInContexts = getDeclShowContexts(Results[I].Declaration,
                                                         Ctx->getLangOptions(),
                                                         IsNestedNameSpecifier);
@@ -294,7 +295,9 @@ void ASTUnit::CacheCodeCompletionResults() {
           // nested-name-specifier but isn't already an option, create a 
           // nested-name-specifier completion.
           Results[I].StartsNestedNameSpecifier = true;
-          CachedResult.Completion = Results[I].CreateCodeCompletionString(*TheSema);
+          CachedResult.Completion 
+            = Results[I].CreateCodeCompletionString(*TheSema,
+                                                    CachedCompletionAllocator);
           CachedResult.ShowInContexts = RemainingContexts;
           CachedResult.Priority = CCP_NestedNameSpecifier;
           CachedResult.TypeClass = STC_Void;
@@ -313,7 +316,9 @@ void ASTUnit::CacheCodeCompletionResults() {
       
     case Result::RK_Macro: {
       CachedCodeCompletionResult CachedResult;
-      CachedResult.Completion = Results[I].CreateCodeCompletionString(*TheSema);
+      CachedResult.Completion 
+        = Results[I].CreateCodeCompletionString(*TheSema,
+                                                CachedCompletionAllocator);
       CachedResult.ShowInContexts
         = (1 << (CodeCompletionContext::CCC_TopLevel - 1))
         | (1 << (CodeCompletionContext::CCC_ObjCInterface - 1))
@@ -337,7 +342,6 @@ void ASTUnit::CacheCodeCompletionResults() {
       break;
     }
     }
-    Results[I].Destroy();
   }
 
   // Make a note of the state when we performed this caching.
@@ -345,10 +349,9 @@ void ASTUnit::CacheCodeCompletionResults() {
 }
 
 void ASTUnit::ClearCachedCompletionResults() {
-  for (unsigned I = 0, N = CachedCompletionResults.size(); I != N; ++I)
-    delete CachedCompletionResults[I].Completion;
   CachedCompletionResults.clear();
   CachedCompletionTypes.clear();
+  CachedCompletionAllocator.Reset();
 }
 
 namespace {
@@ -1657,6 +1660,10 @@ namespace {
                                            unsigned NumCandidates) { 
       Next.ProcessOverloadCandidates(S, CurrentArg, Candidates, NumCandidates);
     }
+    
+    virtual llvm::BumpPtrAllocator &getAllocator() {
+      return Next.getAllocator();
+    }
   };
 }
 
@@ -1750,7 +1757,6 @@ void AugmentedCodeCompleteConsumer::ProcessCodeCompleteResults(Sema &S,
 
   // Contains the set of names that are hidden by "local" completion results.
   llvm::StringSet<llvm::BumpPtrAllocator> HiddenNames;
-  llvm::SmallVector<CodeCompletionString *, 4> StringsToDestroy;
   typedef CodeCompletionResult Result;
   llvm::SmallVector<Result, 8> AllResults;
   for (ASTUnit::cached_completion_iterator 
@@ -1809,11 +1815,12 @@ void AugmentedCodeCompleteConsumer::ProcessCodeCompleteResults(Sema &S,
         Context.getKind() == CodeCompletionContext::CCC_MacroNameUse) {
       // Create a new code-completion string that just contains the
       // macro name, without its arguments.
-      Completion = new CodeCompletionString;
-      Completion->AddTypedTextChunk(C->Completion->getTypedText());
-      StringsToDestroy.push_back(Completion);
+      CodeCompletionBuilder Builder(getAllocator(), CCP_CodePattern,
+                                    C->Availability);
+      Builder.AddTypedTextChunk(C->Completion->getTypedText());
       CursorKind = CXCursor_NotImplemented;
       Priority = CCP_CodePattern;
+      Completion = Builder.TakeString();
     }
     
     AllResults.push_back(Result(Completion, Priority, CursorKind, 
@@ -1829,9 +1836,6 @@ void AugmentedCodeCompleteConsumer::ProcessCodeCompleteResults(Sema &S,
   
   Next.ProcessCodeCompleteResults(S, Context, AllResults.data(),
                                   AllResults.size());
-  
-  for (unsigned I = 0, N = StringsToDestroy.size(); I != N; ++I)
-    delete StringsToDestroy[I];
 }
 
 
diff --git a/lib/Sema/CodeCompleteConsumer.cpp b/lib/Sema/CodeCompleteConsumer.cpp
index ee6fb3bf0e..ddfe8b0b17 100644
--- a/lib/Sema/CodeCompleteConsumer.cpp
+++ b/lib/Sema/CodeCompleteConsumer.cpp
@@ -71,7 +71,7 @@ bool CodeCompletionContext::wantConstructorResults() const {
 //===----------------------------------------------------------------------===//
 // Code completion string implementation
 //===----------------------------------------------------------------------===//
-CodeCompletionString::Chunk::Chunk(ChunkKind Kind, llvm::StringRef Text) 
+CodeCompletionString::Chunk::Chunk(ChunkKind Kind, const char *Text) 
   : Kind(Kind), Text("")
 {
   switch (Kind) {
@@ -80,13 +80,9 @@ CodeCompletionString::Chunk::Chunk(ChunkKind Kind, llvm::StringRef Text)
   case CK_Placeholder:
   case CK_Informative:
   case CK_ResultType:
-  case CK_CurrentParameter: {
-    char *New = new char [Text.size() + 1];
-    std::memcpy(New, Text.data(), Text.size());
-    New[Text.size()] = '\0';
-    this->Text = New;
+  case CK_CurrentParameter:
+    this->Text = Text;
     break;
-  }
 
   case CK_Optional:
     llvm_unreachable("Optional strings cannot be created from text");
@@ -151,112 +147,48 @@ CodeCompletionString::Chunk::Chunk(ChunkKind Kind, llvm::StringRef Text)
 }
 
 CodeCompletionString::Chunk
-CodeCompletionString::Chunk::CreateText(StringRef Text) {
+CodeCompletionString::Chunk::CreateText(const char *Text) {
   return Chunk(CK_Text, Text);
 }
 
 CodeCompletionString::Chunk 
-CodeCompletionString::Chunk::CreateOptional(
-                                 std::auto_ptr<CodeCompletionString> Optional) {
+CodeCompletionString::Chunk::CreateOptional(CodeCompletionString *Optional) {
   Chunk Result;
   Result.Kind = CK_Optional;
-  Result.Optional = Optional.release();
+  Result.Optional = Optional;
   return Result;
 }
 
 CodeCompletionString::Chunk 
-CodeCompletionString::Chunk::CreatePlaceholder(StringRef Placeholder) {
+CodeCompletionString::Chunk::CreatePlaceholder(const char *Placeholder) {
   return Chunk(CK_Placeholder, Placeholder);
 }
 
 CodeCompletionString::Chunk 
-CodeCompletionString::Chunk::CreateInformative(StringRef Informative) {
+CodeCompletionString::Chunk::CreateInformative(const char *Informative) {
   return Chunk(CK_Informative, Informative);
 }
 
 CodeCompletionString::Chunk 
-CodeCompletionString::Chunk::CreateResultType(StringRef ResultType) {
+CodeCompletionString::Chunk::CreateResultType(const char *ResultType) {
   return Chunk(CK_ResultType, ResultType);
 }
 
 CodeCompletionString::Chunk 
 CodeCompletionString::Chunk::CreateCurrentParameter(
-                                                StringRef CurrentParameter) {
+                                                const char *CurrentParameter) {
   return Chunk(CK_CurrentParameter, CurrentParameter);
 }
 
-CodeCompletionString::Chunk CodeCompletionString::Chunk::Clone() const {
-  switch (Kind) {
-  case CK_TypedText:
-  case CK_Text:
-  case CK_Placeholder:
-  case CK_Informative:
-  case CK_ResultType:
-  case CK_CurrentParameter:
-  case CK_LeftParen:
-  case CK_RightParen:
-  case CK_LeftBracket:
-  case CK_RightBracket:
-  case CK_LeftBrace:
-  case CK_RightBrace:
-  case CK_LeftAngle:
-  case CK_RightAngle:
-  case CK_Comma:
-  case CK_Colon:
-  case CK_SemiColon:
-  case CK_Equal:
-  case CK_HorizontalSpace:
-  case CK_VerticalSpace:
-    return Chunk(Kind, Text);
-      
-  case CK_Optional: {
-    std::auto_ptr<CodeCompletionString> Opt(Optional->Clone());
-    return CreateOptional(Opt);
-  }
-  }
-
-  // Silence GCC warning.
-  return Chunk();
-}
-
-void
-CodeCompletionString::Chunk::Destroy() {
-  switch (Kind) {
-  case CK_Optional: 
-    delete Optional; 
-    break;
-      
-  case CK_TypedText:
-  case CK_Text: 
-  case CK_Placeholder:
-  case CK_Informative:
-  case CK_ResultType:
-  case CK_CurrentParameter:
-    delete [] Text;
-    break;
-
-  case CK_LeftParen:
-  case CK_RightParen:
-  case CK_LeftBracket:
-  case CK_RightBracket:
-  case CK_LeftBrace:
-  case CK_RightBrace:
-  case CK_LeftAngle:
-  case CK_RightAngle:
-  case CK_Comma:
-  case CK_Colon:
-  case CK_SemiColon:
-  case CK_Equal:
-  case CK_HorizontalSpace:
-  case CK_VerticalSpace:
-    break;
-  }
-}
-
-void CodeCompletionString::clear() {
-  std::for_each(Chunks.begin(), Chunks.end(), 
-                std::mem_fun_ref(&Chunk::Destroy));
-  Chunks.clear();
+CodeCompletionString::CodeCompletionString(const Chunk *Chunks, 
+                                           unsigned NumChunks,
+                                           unsigned Priority, 
+                                           CXAvailabilityKind Availability) 
+  : NumChunks(NumChunks), Priority(Priority), Availability(Availability) 
+{ 
+  Chunk *StoredChunks = reinterpret_cast<Chunk *>(this + 1);
+  for (unsigned I = 0; I != NumChunks; ++I)
+    StoredChunks[I] = Chunks[I];
 }
 
 std::string CodeCompletionString::getAsString() const {
@@ -288,22 +220,17 @@ const char *CodeCompletionString::getTypedText() const {
   return 0;
 }
 
-CodeCompletionString *
-CodeCompletionString::Clone(CodeCompletionString *Result) const {
-  if (!Result)
-    Result = new CodeCompletionString;
-  for (iterator C = begin(), CEnd = end(); C != CEnd; ++C)
-    Result->AddChunk(C->Clone());
+CodeCompletionString *CodeCompletionBuilder::TakeString() {
+  void *Mem = Allocator.Allocate(
+                  sizeof(CodeCompletionString) + sizeof(Chunk) * Chunks.size(), 
+                                 llvm::alignOf<CodeCompletionString>());
+  CodeCompletionString *Result 
+    = new (Mem) CodeCompletionString(Chunks.data(), Chunks.size(),
+                               Priority, Availability);
+  Chunks.clear();
   return Result;
 }
 
-void CodeCompletionResult::Destroy() {
-  if (Kind == RK_Pattern) {
-    delete Pattern;
-    Pattern = 0;
-  }
-}
-
 unsigned CodeCompletionResult::getPriorityFromDecl(NamedDecl *ND) {
   if (!ND)
     return CCP_Unlikely;
@@ -383,9 +310,8 @@ PrintingCodeCompleteConsumer::ProcessCodeCompleteResults(Sema &SemaRef,
       if (Results[I].Hidden)
         OS << " (Hidden)";
       if (CodeCompletionString *CCS 
-            = Results[I].CreateCodeCompletionString(SemaRef)) {
+            = Results[I].CreateCodeCompletionString(SemaRef, Allocator)) {
         OS << " : " << CCS->getAsString();
-        delete CCS;
       }
         
       OS << '\n';
@@ -398,9 +324,8 @@ PrintingCodeCompleteConsumer::ProcessCodeCompleteResults(Sema &SemaRef,
     case CodeCompletionResult::RK_Macro: {
       OS << Results[I].Macro->getName();
       if (CodeCompletionString *CCS 
-            = Results[I].CreateCodeCompletionString(SemaRef)) {
+            = Results[I].CreateCodeCompletionString(SemaRef, Allocator)) {
         OS << " : " << CCS->getAsString();
-        delete CCS;
       }
       OS << '\n';
       break;
@@ -422,9 +347,9 @@ PrintingCodeCompleteConsumer::ProcessOverloadCandidates(Sema &SemaRef,
                                                      unsigned NumCandidates) {
   for (unsigned I = 0; I != NumCandidates; ++I) {
     if (CodeCompletionString *CCS
-          = Candidates[I].CreateSignatureString(CurrentArg, SemaRef)) {
+          = Candidates[I].CreateSignatureString(CurrentArg, SemaRef,
+                                                Allocator)) {
       OS << "OVERLOAD: " << CCS->getAsString() << "\n";
-      delete CCS;
     }
   }
 }
diff --git a/lib/Sema/SemaCodeComplete.cpp b/lib/Sema/SemaCodeComplete.cpp
index 50ea6cb0b5..051603ce6d 100644
--- a/lib/Sema/SemaCodeComplete.cpp
+++ b/lib/Sema/SemaCodeComplete.cpp
@@ -117,6 +117,9 @@ namespace {
     /// \brief The semantic analysis object for which results are being 
     /// produced.
     Sema &SemaRef;
+
+    /// \brief The allocator used to allocate new code-completion strings.
+    llvm::BumpPtrAllocator &Allocator;
     
     /// \brief If non-NULL, a filter function used to remove any code-completion
     /// results that are not desirable.
@@ -159,11 +162,11 @@ namespace {
     void MaybeAddConstructorResults(Result R);
     
   public:
-    explicit ResultBuilder(Sema &SemaRef, 
+    explicit ResultBuilder(Sema &SemaRef, llvm::BumpPtrAllocator &Allocator,
                            const CodeCompletionContext &CompletionContext,
                            LookupFilter Filter = 0)
-      : SemaRef(SemaRef), Filter(Filter), AllowNestedNameSpecifiers(false),
-        HasObjectTypeQualifiers(false), 
+      : SemaRef(SemaRef), Allocator(Allocator), Filter(Filter), 
+        AllowNestedNameSpecifiers(false), HasObjectTypeQualifiers(false), 
         CompletionContext(CompletionContext),
         ObjCImplementation(0) 
     { 
@@ -243,6 +246,9 @@ namespace {
     /// code completion results.
     Sema &getSema() const { return SemaRef; }
     
+    /// \brief Retrieve the allocator used to allocate code completion strings.
+    llvm::BumpPtrAllocator &getAllocator() const { return Allocator; }
+    
     /// \brief Determine whether the given declaration is at all interesting
     /// as a code-completion result.
     ///
@@ -1189,6 +1195,7 @@ static void AddTypeSpecifierResults(const LangOptions &LangOpts,
     Results.AddResult(Result("restrict", CCP_Type));
   }
   
+  CodeCompletionBuilder Builder(Results.getAllocator());
   if (LangOpts.CPlusPlus) {
     // C++-specific
     Results.AddResult(Result("bool", CCP_Type + 
@@ -1197,25 +1204,23 @@ static void AddTypeSpecifierResults(const LangOptions &LangOpts,
     Results.AddResult(Result("wchar_t", CCP_Type));
     
     // typename qualified-id
-    CodeCompletionString *Pattern = new CodeCompletionString;
-    Pattern->AddTypedTextChunk("typename");
-    Pattern->AddChunk(CodeCompletionString::CK_HorizontalSpace);
-    Pattern->AddPlaceholderChunk("qualifier");
-    Pattern->AddTextChunk("::");
-    Pattern->AddPlaceholderChunk("name");
-    Results.AddResult(Result(Pattern));
+    Builder.AddTypedTextChunk("typename");
+    Builder.AddChunk(CodeCompletionString::CK_HorizontalSpace);
+    Builder.AddPlaceholderChunk("qualifier");
+    Builder.AddTextChunk("::");
+    Builder.AddPlaceholderChunk("name");
+    Results.AddResult(Result(Builder.TakeString()));
     
     if (LangOpts.CPlusPlus0x) {
       Results.AddResult(Result("auto", CCP_Type));
       Results.AddResult(Result("char16_t", CCP_Type));
       Results.AddResult(Result("char32_t", CCP_Type));
       
-      CodeCompletionString *Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("decltype");
-      Pattern->AddChunk(CodeCompletionString::CK_LeftParen);
-      Pattern->AddPlaceholderChunk("expression");
-      Pattern->AddChunk(CodeCompletionString::CK_RightParen);
-      Results.AddResult(Result(Pattern));
+      Builder.AddTypedTextChunk("decltype");
+      Builder.AddChunk(CodeCompletionString::CK_LeftParen);
+      Builder.AddPlaceholderChunk("expression");
+      Builder.AddChunk(CodeCompletionString::CK_RightParen);
+      Results.AddResult(Result(Builder.TakeString()));
     }
   }
   
@@ -1226,18 +1231,16 @@ static void AddTypeSpecifierResults(const LangOptions &LangOpts,
     //    Results.AddResult(Result("_Decimal64"));
     //    Results.AddResult(Result("_Decimal128"));
     
-    CodeCompletionString *Pattern = new CodeCompletionString;
-    Pattern->AddTypedTextChunk("typeof");
-    Pattern->AddChunk(CodeCompletionString::CK_HorizontalSpace);
-    Pattern->AddPlaceholderChunk("expression");
-    Results.AddResult(Result(Pattern));
+    Builder.AddTypedTextChunk("typeof");
+    Builder.AddChunk(CodeCompletionString::CK_HorizontalSpace);
+    Builder.AddPlaceholderChunk("expression");
+    Results.AddResult(Result(Builder.TakeString()));
 
-    Pattern = new CodeCompletionString;
-    Pattern->AddTypedTextChunk("typeof");
-    Pattern->AddChunk(CodeCompletionString::CK_LeftParen);
-    Pattern->AddPlaceholderChunk("type");
-    Pattern->AddChunk(CodeCompletionString::CK_RightParen);
-    Results.AddResult(Result(Pattern));
+    Builder.AddTypedTextChunk("typeof");
+    Builder.AddChunk(CodeCompletionString::CK_LeftParen);
+    Builder.AddPlaceholderChunk("type");
+    Builder.AddChunk(CodeCompletionString::CK_RightParen);
+    Results.AddResult(Result(Builder.TakeString()));
   }
 }
 
@@ -1301,13 +1304,13 @@ static void AddObjCInterfaceResults(const LangOptions &LangOpts,
 static void AddObjCTopLevelResults(ResultBuilder &Results, bool NeedAt);
 
 static void AddTypedefResult(ResultBuilder &Results) {
-  CodeCompletionString *Pattern = new CodeCompletionString;
-  Pattern->AddTypedTextChunk("typedef");
-  Pattern->AddChunk(CodeCompletionString::CK_HorizontalSpace);
-  Pattern->AddPlaceholderChunk("type");
-  Pattern->AddChunk(CodeCompletionString::CK_HorizontalSpace);
-  Pattern->AddPlaceholderChunk("name");
-  Results.AddResult(CodeCompletionResult(Pattern));        
+  CodeCompletionBuilder Builder(Results.getAllocator());
+  Builder.AddTypedTextChunk("typedef");
+  Builder.AddChunk(CodeCompletionString::CK_HorizontalSpace);
+  Builder.AddPlaceholderChunk("type");
+  Builder.AddChunk(CodeCompletionString::CK_HorizontalSpace);
+  Builder.AddPlaceholderChunk("name");
+  Results.AddResult(CodeCompletionResult(Builder.TakeString()));        
 }
 
 static bool WantTypesInContext(Sema::ParserCompletionContext CCC,
@@ -1344,58 +1347,53 @@ static void AddOrdinaryNameResults(Sema::ParserCompletionContext CCC,
                                    Scope *S,
                                    Sema &SemaRef,
                                    ResultBuilder &Results) {
+  CodeCompletionBuilder Builder(Results.getAllocator());
+  
   typedef CodeCompletionResult Result;
   switch (CCC) {
   case Sema::PCC_Namespace:
     if (SemaRef.getLangOptions().CPlusPlus) {
-      CodeCompletionString *Pattern = 0;
-      
       if (Results.includeCodePatterns()) {
         // namespace <identifier> { declarations }
-        CodeCompletionString *Pattern = new CodeCompletionString;
-        Pattern->AddTypedTextChunk("namespace");
-        Pattern->AddChunk(CodeCompletionString::CK_HorizontalSpace);
-        Pattern->AddPlaceholderChunk("identifier");
-        Pattern->AddChunk(CodeCompletionString::CK_LeftBrace);
-        Pattern->AddPlaceholderChunk("declarations");
-        Pattern->AddChunk(CodeCompletionString::CK_VerticalSpace);
-        Pattern->AddChunk(CodeCompletionString::CK_RightBrace);
-        Results.AddResult(Result(Pattern));
+        Builder.AddTypedTextChunk("namespace");
+        Builder.AddChunk(CodeCompletionString::CK_HorizontalSpace);
+        Builder.AddPlaceholderChunk("identifier");
+        Builder.AddChunk(CodeCompletionString::CK_LeftBrace);
+        Builder.AddPlaceholderChunk("declarations");
+        Builder.AddChunk(CodeCompletionString::CK_VerticalSpace);
+        Builder.AddChunk(CodeCompletionString::CK_RightBrace);
+        Results.AddResult(Result(Builder.TakeString()));
       }
       
       // namespace identifier = identifier ;
-      Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("namespace");
-      Pattern->AddChunk(CodeCompletionString::CK_HorizontalSpace);
-      Pattern->AddPlaceholderChunk("name");
-      Pattern->AddChunk(CodeCompletionString::CK_Equal);
-      Pattern->AddPlaceholderChunk("namespace");
-      Results.AddResult(Result(Pattern));
+      Builder.AddTypedTextChunk("namespace");
+      Builder.AddChunk(CodeCompletionString::CK_HorizontalSpace);
+      Builder.AddPlaceholderChunk("name");
+      Builder.AddChunk(CodeCompletionString::CK_Equal);
+      Builder.AddPlaceholderChunk("namespace");
+      Results.AddResult(Result(Builder.TakeString()));
 
       // Using directives
-      Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("using");
-      Pattern->AddChunk(CodeCompletionString::CK_HorizontalSpace);
-      Pattern->AddTextChunk("namespace");
-      Pattern->AddChunk(CodeCompletionString::CK_HorizontalSpace);
-      Pattern->AddPlaceholderChunk("identifier");
-      Results.AddResult(Result(Pattern));
+      Builder.AddTypedTextChunk("using");
+      Builder.AddChunk(CodeCompletionString::CK_HorizontalSpace);
+      Builder.AddTextChunk("namespace");
+      Builder.AddChunk(CodeCompletionString::CK_HorizontalSpace);
+      Builder.AddPlaceholderChunk("identifier");
+      Results.AddResult(Result(Builder.TakeString()));
 
       // asm(string-literal)      
-      Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("asm");
-      Pattern->AddChunk(CodeCompletionString::CK_LeftParen);
-      Pattern->AddPlaceholderChunk("string-literal");
-      Pattern->AddChunk(CodeCompletionString::CK_RightParen);
-      Results.AddResult(Result(Pattern));
+      Builder.AddTypedTextChunk("asm");
+      Builder.AddChunk(CodeCompletionString::CK_LeftParen);
+      Builder.AddPlaceholderChunk("string-literal");
+      Builder.AddChunk(CodeCompletionString::CK_RightParen);
+      Results.AddResult(Result(Builder.TakeString()));
 
       if (Results.includeCodePatterns()) {
         // Explicit template instantiation
-        Pattern = new CodeCompletionString;
-        Pattern->AddTypedTextChunk("template");
-        Pattern->AddChunk(CodeCompletionString::CK_HorizontalSpace);
-        Pattern->AddPlaceholderChunk("declaration");
-        Results.AddResult(Result(Pattern));
+        Builder.AddTypedTextChunk("template");
+        Builder.AddChunk(CodeCompletionString::CK_HorizontalSpace);
+        Builder.AddPlaceholderChunk("declaration");
+        Results.AddResult(Result(Builder.TakeString()));
       }
     }
       
@@ -1408,47 +1406,42 @@ static void AddOrdinaryNameResults(Sema::ParserCompletionContext CCC,
   case Sema::PCC_Class:
     if (SemaRef.getLangOptions().CPlusPlus) {
       // Using declaration
-      CodeCompletionString *Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("using");
-      Pattern->AddChunk(CodeCompletionString::CK_HorizontalSpace);
-      Pattern->AddPlaceholderChunk("qualifier");
-      Pattern->AddTextChunk("::");
-      Pattern->AddPlaceholderChunk("name");
-      Results.AddResult(Result(Pattern));
+      Builder.AddTypedTextChunk("using");
+      Builder.AddChunk(CodeCompletionString::CK_HorizontalSpace);
+      Builder.AddPlaceholderChunk("qualifier");
+      Builder.AddTextChunk("::");
+      Builder.AddPlaceholderChunk("name");
+      Results.AddResult(Result(Builder.TakeString()));
       
       // using typename qualifier::name (only in a dependent context)
       if (SemaRef.CurContext->isDependentContext()) {
-        Pattern = new CodeCompletionString;
-        Pattern->AddTypedTextChunk("using");
-        Pattern->AddChunk(CodeCompletionString::CK_HorizontalSpace);
-        Pattern->AddTextChunk("typename");
-        Pattern->AddChunk(CodeCompletionString::CK_HorizontalSpace);
-        Pattern->AddPlaceholderChunk("qualifier");
-        Pattern->AddTextChunk("::");
-        Pattern->AddPlaceholderChunk("name");
-        Results.AddResult(Result(Pattern));
+        Builder.AddTypedTextChunk("using");
+        Builder.AddChunk(CodeCompletionString::CK_HorizontalSpace);
+        Builder.AddTextChunk("typename");
+        Builder.AddChunk(CodeCompletionString::CK_HorizontalSpace);
+        Builder.AddPlaceholderChunk("qualifier");
+        Builder.AddTextChunk("::");
+        Builder.AddPlaceholderChunk("name");
+        Results.AddResult(Result(Builder.TakeString()));
       }
 
       if (CCC == Sema::PCC_Class) {
         AddTypedefResult(Results);
 
         // public:
-        Pattern = new CodeCompletionString;
-        Pattern->AddTypedTextChunk("public");
-        Pattern->AddChunk(CodeCompletionString::CK_Colon);
-        Results.AddResult(Result(Pattern));
+        Builder.AddTypedTextChunk("public");
+        Builder.AddChunk(CodeCompletionString::CK_Colon);
+        Results.AddResult(Result(Builder.TakeString()));
 
         // protected:
-        Pattern = new CodeCompletionString;
-        Pattern->AddTypedTextChunk("protected");
-        Pattern->AddChunk(CodeCompletionString::CK_Colon);
-        Results.AddResult(Result(Pattern));
+        Builder.AddTypedTextChunk("protected");
+        Builder.AddChunk(CodeCompletionString::CK_Colon);
+        Results.AddResult(Result(Builder.TakeString()));
 
         // private:
-        Pattern = new CodeCompletionString;
-        Pattern->AddTypedTextChunk("private");
-        Pattern->AddChunk(CodeCompletionString::CK_Colon);
-        Results.AddResult(Result(Pattern));
+        Builder.AddTypedTextChunk("private");
+        Builder.AddChunk(CodeCompletionString::CK_Colon);
+        Results.AddResult(Result(Builder.TakeString()));
       }
     }
     // Fall through
@@ -1457,12 +1450,11 @@ static void AddOrdinaryNameResults(Sema::ParserCompletionContext CCC,
   case Sema::PCC_MemberTemplate:
     if (SemaRef.getLangOptions().CPlusPlus && Results.includeCodePatterns()) {
       // template < parameters >
-      CodeCompletionString *Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("template");
-      Pattern->AddChunk(CodeCompletionString::CK_LeftAngle);
-      Pattern->AddPlaceholderChunk("parameters");
-      Pattern->AddChunk(CodeCompletionString::CK_RightAngle);
-      Results.AddResult(Result(Pattern));
+      Builder.AddTypedTextChunk("template");
+      Builder.AddChunk(CodeCompletionString::CK_LeftAngle);
+      Builder.AddPlaceholderChunk("parameters");
+      Builder.AddChunk(CodeCompletionString::CK_RightAngle);
+      Results.AddResult(Result(Builder.TakeString()));
     }
 
     AddStorageSpecifiers(CCC, SemaRef.getLangOptions(), Results);
@@ -1489,137 +1481,126 @@ static void AddOrdinaryNameResults(Sema::ParserCompletionContext CCC,
   case Sema::PCC_Statement: {
     AddTypedefResult(Results);
 
-    CodeCompletionString *Pattern = 0;
     if (SemaRef.getLangOptions().CPlusPlus && Results.includeCodePatterns()) {
-      Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("try");
-      Pattern->AddChunk(CodeCompletionString::CK_LeftBrace);
-      Pattern->AddPlaceholderChunk("statements");
-      Pattern->AddChunk(CodeCompletionString::CK_VerticalSpace);
-      Pattern->AddChunk(CodeCompletionString::CK_RightBrace);
-      Pattern->AddTextChunk("catch");
-      Pattern->AddChunk(CodeCompletionString::CK_LeftParen);
-      Pattern->AddPlaceholderChunk("declaration");
-      Pattern->AddChunk(CodeCompletionString::CK_RightParen);
-      Pattern->AddChunk(CodeCompletionString::CK_LeftBrace);
-      Pattern->AddPlaceholderChunk("statements");
-      Pattern->AddChunk(CodeCompletionString::CK_VerticalSpace);
-      Pattern->AddChunk(CodeCompletionString::CK_RightBrace);
-      Results.AddResult(Result(Pattern));
+      Builder.AddTypedTextChunk("try");
+      Builder.AddChunk(CodeCompletionString::CK_LeftBrace);
+      Builder.AddPlaceholderChunk("statements");
+      Builder.AddChunk(CodeCompletionString::CK_VerticalSpace);
+      Builder.AddChunk(CodeCompletionString::CK_RightBrace);
+      Builder.AddTextChunk("catch");
+      Builder.AddChunk(CodeCompletionString::CK_LeftParen);
+      Builder.AddPlaceholderChunk("declaration");
+      Builder.AddChunk(CodeCompletionString::CK_RightParen);
+      Builder.AddChunk(CodeCompletionString::CK_LeftBrace);
+      Builder.AddPlaceholderChunk("statements");
+      Builder.AddChunk(CodeCompletionString::CK_VerticalSpace);
+      Builder.AddChunk(CodeCompletionString::CK_RightBrace);
+      Results.AddResult(Result(Builder.TakeString()));
     }
     if (SemaRef.getLangOptions().ObjC1)
       AddObjCStatementResults(Results, true);
     
     if (Results.includeCodePatterns()) {
       // if (condition) { statements }
-      Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("if");
-      Pattern->AddChunk(CodeCompletionString::CK_LeftParen);
+      Builder.AddTypedTextChunk("if");
+      Builder.AddChunk(CodeCompletionString::CK_LeftParen);
       if (SemaRef.getLangOptions().CPlusPlus)
-        Pattern->AddPlaceholderChunk("condition");
+        Builder.AddPlaceholderChunk("condition");
       else
-        Pattern->AddPlaceholderChunk("expression");
-      Pattern->AddChunk(CodeCompletionString::CK_RightParen);
-      Pattern->AddChunk(CodeCompletionString::CK_LeftBrace);
-      Pattern->AddPlaceholderChunk("statements");
-      Pattern->AddChunk(CodeCompletionString::CK_VerticalSpace);
-      Pattern->AddChunk(CodeCompletionString::CK_RightBrace);
-      Results.AddResult(Result(Pattern));
+        Builder.AddPlaceholderChunk("expression");
+      Builder.AddChunk(CodeCompletionString::CK_RightParen);
+      Builder.AddChunk(CodeCompletionString::CK_LeftBrace);
+      Builder.AddPlaceholderChunk("statements");
+      Builder.AddChunk(CodeCompletionString::CK_VerticalSpace);
+      Builder.AddChunk(CodeCompletionString::CK_RightBrace);
+      Results.AddResult(Result(Builder.TakeString()));
 
       // switch (condition) { }
-      Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("switch");
-      Pattern->AddChunk(CodeCompletionString::CK_LeftParen);
+      Builder.AddTypedTextChunk("switch");
+      Builder.AddChunk(CodeCompletionString::CK_LeftParen);
       if (SemaRef.getLangOptions().CPlusPlus)
-        Pattern->AddPlaceholderChunk("condition");
+        Builder.AddPlaceholderChunk("condition");
       else
-        Pattern->AddPlaceholderChunk("expression");
-      Pattern->AddChunk(CodeCompletionString::CK_RightParen);
-      Pattern->AddChunk(CodeCompletionString::CK_LeftBrace);
-      Pattern->AddChunk(CodeCompletionString::CK_VerticalSpace);
-      Pattern->AddChunk(CodeCompletionString::CK_RightBrace);
-      Results.AddResult(Result(Pattern));
+        Builder.AddPlaceholderChunk("expression");
+      Builder.AddChunk(CodeCompletionString::CK_RightParen);
+      Builder.AddChunk(CodeCompletionString::CK_LeftBrace);
+      Builder.AddChunk(CodeCompletionString::CK_VerticalSpace);
+      Builder.AddChunk(CodeCompletionString::CK_RightBrace);
+      Results.AddResult(Result(Builder.TakeString()));
     }
     
     // Switch-specific statements.
     if (!SemaRef.getCurFunction()->SwitchStack.empty()) {
       // case expression:
-      Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("case");
-      Pattern->AddChunk(CodeCompletionString::CK_HorizontalSpace);
-      Pattern->AddPlaceholderChunk("expression");
-      Pattern->AddChunk(CodeCompletionString::CK_Colon);
-      Results.AddResult(Result(Pattern));
+      Builder.AddTypedTextChunk("case");
+      Builder.AddChunk(CodeCompletionString::CK_HorizontalSpace);
+      Builder.AddPlaceholderChunk("expression");
+      Builder.AddChunk(CodeCompletionString::CK_Colon);
+      Results.AddResult(Result(Builder.TakeString()));
 
       // default:
-      Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("default");
-      Pattern->AddChunk(CodeCompletionString::CK_Colon);
-      Results.AddResult(Result(Pattern));
+      Builder.AddTypedTextChunk("default");
+      Builder.AddChunk(CodeCompletionString::CK_Colon);
+      Results.AddResult(Result(Builder.TakeString()));
     }
 
     if (Results.includeCodePatterns()) {
       /// while (condition) { statements }
-      Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("while");
-      Pattern->AddChunk(CodeCompletionString::CK_LeftParen);
+      Builder.AddTypedTextChunk("while");
+      Builder.AddChunk(CodeCompletionString::CK_LeftParen);
       if (SemaRef.getLangOptions().CPlusPlus)
-        Pattern->AddPlaceholderChunk("condition");
+        Builder.AddPlaceholderChunk("condition");
       else
-        Pattern->AddPlaceholderChunk("expression");
-      Pattern->AddChunk(CodeCompletionString::CK_RightParen);
-      Pattern->AddChunk(CodeCompletionString::CK_LeftBrace);
-      Pattern->AddPlaceholderChunk("statements");
-      Pattern->AddChunk(CodeCompletionString::CK_VerticalSpace);
-      Pattern->AddChunk(CodeCompletionString::CK_RightBrace);
-      Results.AddResult(Result(Pattern));
+        Builder.AddPlaceholderChunk("expression");
+      Builder.AddChunk(CodeCompletionString::CK_RightParen);
+      Builder.AddChunk(CodeCompletionString::CK_LeftBrace);
+      Builder.AddPlaceholderChunk("statements");
+      Builder.AddChunk(CodeCompletionString::CK_VerticalSpace);
+      Builder.AddChunk(CodeCompletionString::CK_RightBrace);
+      Results.AddResult(Result(Builder.TakeString()));
 
       // do { statements } while ( expression );
-      Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("do");
-      Pattern->AddChunk(CodeCompletionString::CK_LeftBrace);
-      Pattern->AddPlaceholderChunk("statements");
-      Pattern->AddChunk(CodeCompletionString::CK_VerticalSpace);
-      Pattern->AddChunk(CodeCompletionString::CK_RightBrace);
-      Pattern->AddTextChunk("while");
-      Pattern->AddChunk(CodeCompletionString::CK_LeftParen);
-      Pattern->AddPlaceholderChunk("expression");
-      Pattern->AddChunk(CodeCompletionString::CK_RightParen);
-      Results.AddResult(Result(Pattern));
+      Builder.AddTypedTextChunk("do");
+      Builder.AddChunk(CodeCompletionString::CK_LeftBrace);
+      Builder.AddPlaceholderChunk("statements");
+      Builder.AddChunk(CodeCompletionString::CK_VerticalSpace);
+      Builder.AddChunk(CodeCompletionString::CK_RightBrace);
+      Builder.AddTextChunk("while");
+      Builder.AddChunk(CodeCompletionString::CK_LeftParen);
+      Builder.AddPlaceholderChunk("expression");
+      Builder.AddChunk(CodeCompletionString::CK_RightParen);
+      Results.AddResult(Result(Builder.TakeString()));
 
       // for ( for-init-statement ; condition ; expression ) { statements }
-      Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("for");
-      Pattern->AddChunk(CodeCompletionString::CK_LeftParen);
+      Builder.AddTypedTextChunk("for");
+      Builder.AddChunk(CodeCompletionString::CK_LeftParen);
       if (SemaRef.getLangOptions().CPlusPlus || SemaRef.getLangOptions().C99)
-        Pattern->AddPlaceholderChunk("init-statement");
+        Builder.AddPlaceholderChunk("init-statement");
       else
-        Pattern->AddPlaceholderChunk("init-expression");
-      Pattern->AddChunk(CodeCompletionString::CK_SemiColon);
-      Pattern->AddPlaceholderChunk("condition");
-      Pattern->AddChunk(CodeCompletionString::CK_SemiColon);
-      Pattern->AddPlaceholderChunk("inc-expression");
-      Pattern->AddChunk(CodeCompletionString::CK_RightParen);
-      Pattern->AddChunk(CodeCompletionString::CK_LeftBrace);
-      Pattern->AddChunk(CodeCompletionString::CK_VerticalSpace);
-      Pattern->AddPlaceholderChunk("statements");
-      Pattern->AddChunk(CodeCompletionString::CK_VerticalSpace);
-      Pattern->AddChunk(CodeCompletionString::CK_RightBrace);
-      Results.AddResult(Result(Pattern));
+        Builder.AddPlaceholderChunk("init-expression");
+      Builder.AddChunk(CodeCompletionString::CK_SemiColon);
+      Builder.AddPlaceholderChunk("condition");
+      Builder.AddChunk(CodeCompletionString::CK_SemiColon);
+      Builder.AddPlaceholderChunk("inc-expression");
+      Builder.AddChunk(CodeCompletionString::CK_RightParen);
+      Builder.AddChunk(CodeCompletionString::CK_LeftBrace);
+      Builder.AddChunk(CodeCompletionString::CK_VerticalSpace);
+      Builder.AddPlaceholderChunk("statements");
+      Builder.AddChunk(CodeCompletionString::CK_VerticalSpace);
+      Builder.AddChunk(CodeCompletionString::CK_RightBrace);
+      Results.AddResult(Result(Builder.TakeString()));
     }
     
     if (S->getContinueParent()) {
       // continue ;
-      Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("continue");
-      Results.AddResult(Result(Pattern));
+      Builder.AddTypedTextChunk("continue");
+      Results.AddResult(Result(Builder.TakeString()));
     }
 
     if (S->getBreakParent()) {
       // break ;
-      Pattern = new CodeCompletionString;
-      Pattern->AddTypedTextChunk("break");
-      Results.AddResult(Result(Pattern));
+      Builder.AddTypedTextChunk("break");
+      Results.AddResult(Result(Builder.TakeString()));
     }
 
     // "return expression ;" or "return ;", depending on whether we
@@ -1633,29 +1614,26 @@ static void AddOrdinaryNameResults(Sema::ParserComplet