Install notion of diagnostic handler into PNaCl bitcode readers.

include/llvm/Bitcode/NaCl/NaClReaderWriter.h

Index: include/llvm/Bitcode/NaCl/NaClReaderWriter.h
diff --git a/include/llvm/Bitcode/NaCl/NaClReaderWriter.h b/include/llvm/Bitcode/NaCl/NaClReaderWriter.h
index 6ac74722b3ebc0fbadf3fa46b27969636e81d725..762e51b65f1c09d0e39922782e7d476d8d63ed79 100644
--- a/include/llvm/Bitcode/NaCl/NaClReaderWriter.h
+++ b/include/llvm/Bitcode/NaCl/NaClReaderWriter.h
@@ -16,6 +16,7 @@
 #ifndef LLVM_BITCODE_NACL_NACLREADERWRITER_H
 #define LLVM_BITCODE_NACL_NACLREADERWRITER_H
 
+#include "llvm/IR/DiagnosticInfo.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/ErrorOr.h"
 #include "llvm/Support/MemoryBuffer.h"
@@ -43,13 +44,13 @@ namespace llvm {
   /// \brief Defines the integer bit size used to model pointers in PNaCl.
   static const unsigned PNaClIntPtrTypeBitSize = 32;
 
+  /// Diagnostic handler that redirects error diagnostics to the given stream.
+  DiagnosticHandlerFunction redirectNaClDiagnosticToStream(raw_ostream &Out);
+
   /// Read the header of the specified bitcode buffer and prepare for lazy
   /// deserialization of function bodies.  If successful, this takes ownership
-  /// of 'Buffer' (extending its lifetime).  On error, this returns an error code
-  /// and deletes Buffer.
-  ///
-  /// When Verbose is non-null, more descriptive error messages are also
-  /// written to Verbose.
+  /// of 'Buffer' (extending its lifetime).  On error, this returns an error
+  /// code and deletes Buffer.
   ///
   /// The AcceptSupportedOnly argument is used to decide which PNaCl versions
   /// of the PNaCl bitcode to accept. There are three forms:
@@ -61,37 +62,37 @@ namespace llvm {
   /// AcceptSupportedOnly is false, forms 1 and 2 are allowed.
   ErrorOr<Module *> getNaClLazyBitcodeModule(
       std::unique_ptr<MemoryBuffer> &&Buffer, LLVMContext &Context,
-      raw_ostream *Verbose = nullptr, bool AcceptSupportedOnly = true);
+      DiagnosticHandlerFunction DiagnosticHandler = nullptr,
+      bool AcceptSupportedOnly = true);
 
   /// Read the header of the specified stream and prepare for lazy
   /// deserialization and streaming of function bodies. On error,
   /// this returns null, and fills in *ErrMsg with an error description
   /// if ErrMsg is non-null.
   ///
-  /// See getNaClLazyBitcodeModule for an explanation of arguments
-  /// Verbose, AcceptSupportedOnly.
+  /// See getNaClLazyBitcodeModule for an explanation of argument
+  /// AcceptSupportedOnly.
   /// TODO(kschimpf): Refactor this and getStreamedBitcodeModule to use
   /// ErrorOr<Module *> API so that all methods have the same interface.
-  Module *getNaClStreamedBitcodeModule(const std::string &name,
-                                       StreamingMemoryObject *streamer,
-                                       LLVMContext &Context,
-                                       raw_ostream *Verbose = nullptr,
-                                       std::string *ErrMsg = nullptr,
-                                       bool AcceptSupportedOnly = true);
+  Module *getNaClStreamedBitcodeModule(
+      const std::string &name, StreamingMemoryObject *streamer,
+      LLVMContext &Context,
+      DiagnosticHandlerFunction DiagnosticHandler = nullptr,
+      std::string *ErrMsg = nullptr, bool AcceptSupportedOnly = true);

[Derek Schuff, 2015/08/24 21:22:01]

is ErrMsg used now that we have the diagnostic handler?

[Karl, 2015/08/24 22:23:18]

I didn't clean this up in this patch. I removed the Verbose argument, bit did
not remove ErrMsg, since it had other (small) ramifications on llvm-dis.cpp,
pnacl-llc.cpp, and pnacl-thaw.cpp.

Since I will bit fixing the return type of this function anyway, to match the
external API's used by LLVM, I also play to remove ErrMsg in a separate CL.

 
   /// Read the bitcode file from a buffer, returning the module.
   ///
-  /// See getNaClLazyBitcodeModule for an explanation of arguments
-  /// Verbose, AcceptSupportedOnly.
-  ErrorOr<Module *> NaClParseBitcodeFile(MemoryBufferRef Buffer,
-                                         LLVMContext &Context,
-                                         raw_ostream *Verbose = nullptr,
-                                         bool AcceptSupportedOnly = true);
+  /// See getNaClLazyBitcodeModule for an explanation of argument
+  /// AcceptSupportedOnly.
+  ErrorOr<Module *>
+  NaClParseBitcodeFile(MemoryBufferRef Buffer, LLVMContext &Context,
+                       DiagnosticHandlerFunction DiagnosticHandler = nullptr,
+                       bool AcceptSupportedOnly = true);
 
   /// Read the textual bitcode records in Filename, returning the module.
   /// Note: If Filename is "-", stdin will be read.
   ///
-  /// See getNaClLazyBitcodeModule for an explanation of argument Verbose.
+  /// TODO(kschimpf) Replace Verbose argument with a DiagnosticHandlerFunction.
   ErrorOr<Module *> parseNaClBitcodeText(const std::string &Filename,
                                          LLVMContext &Context,
                                          raw_ostream *Verbose = nullptr);