Frontend: Simplify ownership model for clang's output streams.

This changes the CompilerInstance::createOutputFile function to return
a std::unique_ptr<llvm::raw_ostream>, rather than an llvm::raw_ostream
implicitly owned by the CompilerInstance. This in most cases required that
I move ownership of the output stream to the relevant ASTConsumer.

The motivation for this change is to allow BackendConsumer to be a client
of interfaces such as D20268 which take ownership of the output stream.

Differential Revision: http://reviews.llvm.org/D21537

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@275507 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/CodeGen/BackendUtil.h

@@ -37,7 +37,8 @@ namespace clang {
   void EmitBackendOutput(DiagnosticsEngine &Diags, const CodeGenOptions &CGOpts,
                          const TargetOptions &TOpts, const LangOptions &LOpts,
                          const llvm::DataLayout &TDesc, llvm::Module *M,
-                         BackendAction Action, raw_pwrite_stream *OS);
+                         BackendAction Action,
+                         std::unique_ptr<raw_pwrite_stream> OS);
 
   void EmbedBitcode(llvm::Module *M, const CodeGenOptions &CGOpts,
                     llvm::MemoryBufferRef Buf);

include/clang/CodeGen/ObjectFilePCHContainerOperations.h

@@ -22,10 +22,12 @@ class ObjectFilePCHContainerWriter : public PCHContainerWriter {
   /// Return an ASTConsumer that can be chained with a
   /// PCHGenerator that produces a wrapper file format
   /// that also contains full debug info for the module.
-  std::unique_ptr<ASTConsumer> CreatePCHContainerGenerator(
-      CompilerInstance &CI, const std::string &MainFileName,
-      const std::string &OutputFileName, llvm::raw_pwrite_stream *OS,
-      std::shared_ptr<PCHBuffer> Buffer) const override;
+  std::unique_ptr<ASTConsumer>
+  CreatePCHContainerGenerator(CompilerInstance &CI,
+                              const std::string &MainFileName,
+                              const std::string &OutputFileName,
+                              std::unique_ptr<llvm::raw_pwrite_stream> OS,
+                              std::shared_ptr<PCHBuffer> Buffer) const override;
 };
 
 /// A PCHContainerReader implementation that uses LLVM to

include/clang/Frontend/ASTConsumers.h

@@ -31,7 +31,7 @@ class TargetOptions;
 // original C code.  The output is intended to be in a format such that
 // clang could re-parse the output back into the same AST, but the
 // implementation is still incomplete.
-std::unique_ptr<ASTConsumer> CreateASTPrinter(raw_ostream *OS,
+std::unique_ptr<ASTConsumer> CreateASTPrinter(std::unique_ptr<raw_ostream> OS,
                                               StringRef FilterString);
 
 // AST dumper: dumps the raw AST in human-readable form to stderr; this is

include/clang/Frontend/CompilerInstance.h

@@ -155,15 +155,10 @@ class CompilerInstance : public ModuleLoader {
   struct OutputFile {
     std::string Filename;
     std::string TempFilename;
-    std::unique_ptr<raw_ostream> OS;
-
-    OutputFile(std::string filename, std::string tempFilename,
-               std::unique_ptr<raw_ostream> OS)
-        : Filename(std::move(filename)), TempFilename(std::move(tempFilename)),
-          OS(std::move(OS)) {}
-    OutputFile(OutputFile &&O)
-        : Filename(std::move(O.Filename)),
-          TempFilename(std::move(O.TempFilename)), OS(std::move(O.OS)) {}
+
+    OutputFile(std::string filename, std::string tempFilename)
+        : Filename(std::move(filename)), TempFilename(std::move(tempFilename)) {
+    }
   };
 
   /// If the output doesn't support seeking (terminal, pipe). we switch
@@ -577,8 +572,8 @@ class CompilerInstance : public ModuleLoader {
   /// \param OutFile - The output file info.
   void addOutputFile(OutputFile &&OutFile);
 
-  /// clearOutputFiles - Clear the output file list, destroying the contained
-  /// output streams.
+  /// clearOutputFiles - Clear the output file list. The underlying output
+  /// streams must have been closed beforehand.
   ///
   /// \param EraseFiles - If true, attempt to erase the files from disk.
   void clearOutputFiles(bool EraseFiles);
@@ -685,19 +680,18 @@ class CompilerInstance : public ModuleLoader {
   /// atomically replace the target output on success).
   ///
   /// \return - Null on error.
-  raw_pwrite_stream *createDefaultOutputFile(bool Binary = true,
-                                             StringRef BaseInput = "",
-                                             StringRef Extension = "");
+  std::unique_ptr<raw_pwrite_stream>
+  createDefaultOutputFile(bool Binary = true, StringRef BaseInput = "",
+                          StringRef Extension = "");
 
   /// Create a new output file and add it to the list of tracked output files,
   /// optionally deriving the output path name.
   ///
   /// \return - Null on error.
-  raw_pwrite_stream *createOutputFile(StringRef OutputPath, bool Binary,
-                                      bool RemoveFileOnSignal,
-                                      StringRef BaseInput, StringRef Extension,
-                                      bool UseTemporary,
-                                      bool CreateMissingDirectories = false);
+  std::unique_ptr<raw_pwrite_stream>
+  createOutputFile(StringRef OutputPath, bool Binary, bool RemoveFileOnSignal,
+                   StringRef BaseInput, StringRef Extension, bool UseTemporary,
+                   bool CreateMissingDirectories = false);
 
   /// Create a new output file, optionally deriving the output path name.
   ///
@@ -731,7 +725,7 @@ class CompilerInstance : public ModuleLoader {
                    bool CreateMissingDirectories, std::string *ResultPathName,
                    std::string *TempPathName);
 
-  llvm::raw_null_ostream *createNullOutputFile();
+  std::unique_ptr<raw_pwrite_stream> createNullOutputFile();
 
   /// }
   /// @name Initialization Utility Methods

include/clang/Frontend/FrontendActions.h

@@ -85,7 +85,7 @@ class GeneratePCHAction : public ASTFrontendAction {
   /// create the PCHGenerator instance returned by CreateASTConsumer.
   ///
   /// \returns true if an error occurred, false otherwise.
-  static raw_pwrite_stream *
+  static std::unique_ptr<raw_pwrite_stream>
   ComputeASTConsumerArguments(CompilerInstance &CI, StringRef InFile,
                               std::string &Sysroot, std::string &OutputFile);
 };
@@ -117,10 +117,9 @@ class GenerateModuleAction : public ASTFrontendAction {
   /// create the PCHGenerator instance returned by CreateASTConsumer.
   ///
   /// \returns true if an error occurred, false otherwise.
-  raw_pwrite_stream *ComputeASTConsumerArguments(CompilerInstance &CI,
-                                                 StringRef InFile,
-                                                 std::string &Sysroot,
-                                                 std::string &OutputFile);
+  std::unique_ptr<raw_pwrite_stream>
+  ComputeASTConsumerArguments(CompilerInstance &CI, StringRef InFile,
+                              std::string &Sysroot, std::string &OutputFile);
 };
 
 class SyntaxOnlyAction : public ASTFrontendAction {

include/clang/Frontend/PCHContainerOperations.h

@@ -46,10 +46,12 @@ class PCHContainerWriter {
   /// Return an ASTConsumer that can be chained with a
   /// PCHGenerator that produces a wrapper file format containing a
   /// serialized AST bitstream.
-  virtual std::unique_ptr<ASTConsumer> CreatePCHContainerGenerator(
-      CompilerInstance &CI, const std::string &MainFileName,
-      const std::string &OutputFileName, llvm::raw_pwrite_stream *OS,
-      std::shared_ptr<PCHBuffer> Buffer) const = 0;
+  virtual std::unique_ptr<ASTConsumer>
+  CreatePCHContainerGenerator(CompilerInstance &CI,
+                              const std::string &MainFileName,
+                              const std::string &OutputFileName,
+                              std::unique_ptr<llvm::raw_pwrite_stream> OS,
+                              std::shared_ptr<PCHBuffer> Buffer) const = 0;
 };
 
 /// This abstract interface provides operations for unwrapping
@@ -73,10 +75,12 @@ class RawPCHContainerWriter : public PCHContainerWriter {
 
   /// Return an ASTConsumer that can be chained with a
   /// PCHGenerator that writes the module to a flat file.
-  std::unique_ptr<ASTConsumer> CreatePCHContainerGenerator(
-      CompilerInstance &CI, const std::string &MainFileName,
-      const std::string &OutputFileName, llvm::raw_pwrite_stream *OS,
-      std::shared_ptr<PCHBuffer> Buffer) const override;
+  std::unique_ptr<ASTConsumer>
+  CreatePCHContainerGenerator(CompilerInstance &CI,
+                              const std::string &MainFileName,
+                              const std::string &OutputFileName,
+                              std::unique_ptr<llvm::raw_pwrite_stream> OS,
+                              std::shared_ptr<PCHBuffer> Buffer) const override;
 };
 
 /// Implements read operations for a raw pass-through PCH container.

include/clang/Rewrite/Frontend/ASTConsumers.h

@@ -28,17 +28,18 @@ class Preprocessor;
 // ObjC rewriter: attempts to rewrite ObjC constructs into pure C code.
 // This is considered experimental, and only works with Apple's ObjC runtime.
 std::unique_ptr<ASTConsumer>
-CreateObjCRewriter(const std::string &InFile, raw_ostream *OS,
+CreateObjCRewriter(const std::string &InFile, std::unique_ptr<raw_ostream> OS,
                    DiagnosticsEngine &Diags, const LangOptions &LOpts,
                    bool SilenceRewriteMacroWarning);
 std::unique_ptr<ASTConsumer>
-CreateModernObjCRewriter(const std::string &InFile, raw_ostream *OS,
+CreateModernObjCRewriter(const std::string &InFile,
+                         std::unique_ptr<raw_ostream> OS,
                          DiagnosticsEngine &Diags, const LangOptions &LOpts,
                          bool SilenceRewriteMacroWarning, bool LineInfo);
 
 /// CreateHTMLPrinter - Create an AST consumer which rewrites source code to
 /// HTML with syntax highlighting suitable for viewing in a web-browser.
-std::unique_ptr<ASTConsumer> CreateHTMLPrinter(raw_ostream *OS,
+std::unique_ptr<ASTConsumer> CreateHTMLPrinter(std::unique_ptr<raw_ostream> OS,
                                                Preprocessor &PP,
                                                bool SyntaxHighlight = true,
                                                bool HighlightMacros = true);