Replace a few std::string& with StringRef. NFC.

Patch by Косов Евгений!

llvm-svn: 238774

clang/include/clang/Lex/Lexer.h

@@ -228,7 +228,7 @@ public:
   /// Stringify - Convert the specified string into a C string by escaping '\'
   /// and " characters.  This does not add surrounding ""'s to the string.
   /// If Charify is true, this escapes the ' character instead of ".
-  static std::string Stringify(const std::string &Str, bool Charify = false);
+  static std::string Stringify(StringRef Str, bool Charify = false);
 
   /// Stringify - Convert the specified string into a C string by escaping '\'
   /// and " characters.  This does not add surrounding ""'s to the string.

clang/include/clang/Lex/PPCallbacks.h

@@ -155,7 +155,7 @@ public:
   /// \param Loc The location of the directive.
   /// \param str The text of the directive.
   ///
-  virtual void Ident(SourceLocation Loc, const std::string &str) {
+  virtual void Ident(SourceLocation Loc, StringRef str) {
   }
 
   /// \brief Callback invoked when start reading any pragma directive.
@@ -165,14 +165,13 @@ public:
 
   /// \brief Callback invoked when a \#pragma comment directive is read.
   virtual void PragmaComment(SourceLocation Loc, const IdentifierInfo *Kind,
-                             const std::string &Str) {
+                             StringRef Str) {
   }
 
   /// \brief Callback invoked when a \#pragma detect_mismatch directive is
   /// read.
-  virtual void PragmaDetectMismatch(SourceLocation Loc,
-                                    const std::string &Name,
-                                    const std::string &Value) {
+  virtual void PragmaDetectMismatch(SourceLocation Loc, StringRef Name,
+                                    StringRef Value) {
   }
 
   /// \brief Callback invoked when a \#pragma clang __debug directive is read.
@@ -375,19 +374,19 @@ public:
     Second->EndOfMainFile();
   }
 
-  void Ident(SourceLocation Loc, const std::string &str) override {
+  void Ident(SourceLocation Loc, StringRef str) override {
     First->Ident(Loc, str);
     Second->Ident(Loc, str);
   }
 
   void PragmaComment(SourceLocation Loc, const IdentifierInfo *Kind,
-                     const std::string &Str) override {
+                     StringRef Str) override {
     First->PragmaComment(Loc, Kind, Str);
     Second->PragmaComment(Loc, Kind, Str);
   }
 
-  void PragmaDetectMismatch(SourceLocation Loc, const std::string &Name,
-                            const std::string &Value) override {
+  void PragmaDetectMismatch(SourceLocation Loc, StringRef Name,
+                            StringRef Value) override {
     First->PragmaDetectMismatch(Loc, Name, Value);
     Second->PragmaDetectMismatch(Loc, Name, Value);
   }

clang/include/clang/Lex/PTHManager.h

@@ -129,7 +129,7 @@ public:
 
   /// Create - This method creates PTHManager objects.  The 'file' argument
   ///  is the name of the PTH file.  This method returns NULL upon failure.
-  static PTHManager *Create(const std::string& file, DiagnosticsEngine &Diags);
+  static PTHManager *Create(StringRef file, DiagnosticsEngine &Diags);
 
   void setPreprocessor(Preprocessor *pp) { PP = pp; }
 

clang/include/clang/Lex/Preprocessor.h

@@ -890,7 +890,7 @@ public:
   ///
   /// These predefines are automatically injected when parsing the main file.
   void setPredefines(const char *P) { Predefines = P; }
-  void setPredefines(const std::string &P) { Predefines = P; }
+  void setPredefines(StringRef P) { Predefines = P; }
 
   /// Return information about the specified preprocessor
   /// identifier token.

clang/lib/Frontend/PrintPreprocessedOutput.cpp

@@ -128,7 +128,7 @@ public:
                           CharSourceRange FilenameRange, const FileEntry *File,
                           StringRef SearchPath, StringRef RelativePath,
                           const Module *Imported) override;
-  void Ident(SourceLocation Loc, const std::string &str) override;
+  void Ident(SourceLocation Loc, StringRef str) override;
   void PragmaMessage(SourceLocation Loc, StringRef Namespace,
                      PragmaMessageKind Kind, StringRef Str) override;
   void PragmaDebug(SourceLocation Loc, StringRef DebugType) override;
@@ -337,11 +337,11 @@ void PrintPPOutputPPCallbacks::InclusionDirective(SourceLocation HashLoc,
 
 /// Ident - Handle #ident directives when read by the preprocessor.
 ///
-void PrintPPOutputPPCallbacks::Ident(SourceLocation Loc, const std::string &S) {
+void PrintPPOutputPPCallbacks::Ident(SourceLocation Loc, StringRef S) {
   MoveToLine(Loc);
 
   OS.write("#ident ", strlen("#ident "));
-  OS.write(&S[0], S.size());
+  OS.write(S.begin(), S.size());
   EmittedTokensOnThisLine = true;
 }
 

clang/lib/Lex/Lexer.cpp

@@ -199,7 +199,7 @@ Lexer *Lexer::Create_PragmaLexer(SourceLocation SpellingLoc,
 
 /// Stringify - Convert the specified string into a C string, with surrounding
 /// ""'s, and with escaped \ and " characters.
-std::string Lexer::Stringify(const std::string &Str, bool Charify) {
+std::string Lexer::Stringify(StringRef Str, bool Charify) {
   std::string Result = Str;
   char Quote = Charify ? '\'' : '"';
   for (unsigned i = 0, e = Result.size(); i != e; ++i) {

clang/lib/Lex/PTHLexer.cpp

@@ -431,8 +431,7 @@ static void InvalidPTH(DiagnosticsEngine &Diags, const char *Msg) {
   Diags.Report(Diags.getCustomDiagID(DiagnosticsEngine::Error, "%0")) << Msg;
 }
 
-PTHManager *PTHManager::Create(const std::string &file,
-                               DiagnosticsEngine &Diags) {
+PTHManager *PTHManager::Create(StringRef file, DiagnosticsEngine &Diags) {
   // Memory map the PTH file.
   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> FileOrErr =
       llvm::MemoryBuffer::getFile(file);