Fix pnacl-sz to not accept files containing multiple modules.

src/PNaClTranslator.cpp

 //===- subzero/src/PNaClTranslator.cpp - ICE from bitcode -----------------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 320 matching lines @@
   /// Returns the global declaration (variable or function) with the given
   /// Index.
   Ice::GlobalDeclaration *getGlobalDeclarationByID(NaClBcIndexSize_t Index) {
     size_t NumFunctionIds = FunctionDeclarations.size();
     if (Index < NumFunctionIds)
       return getFunctionByID(Index);
     else
       return getGlobalVariableByID(Index - NumFunctionIds);
   }
 
+  /// Returns true if a module block has been parsed.
+  bool parsedModuleBlock() const { return ParsedModuleBlock; }
+
   /// Returns the list of parsed global variable declarations. Releases
   /// ownership of the current list of global variables. Note: only returns
   /// non-null pointer on first call. All successive calls return a null
   /// pointer.
   std::unique_ptr<Ice::VariableDeclarationList> getGlobalVariables() {
     // Before returning, check that ValidIDConstants has already been built.
     assert(!VariableDeclarations ||
            VariableDeclarations->size() <= ValueIDConstants.size());
     return std::move(VariableDeclarations);
   }
@@ skipping 16 matching lines @@
   // function.
   size_t NextDefiningFunctionID = 0;
   // The set of global variables.
   std::unique_ptr<Ice::VariableDeclarationList> VariableDeclarations;
   // Relocatable constants associated with global declarations.
   Ice::ConstantList ValueIDConstants;
   // Error recovery value to use when getFuncSigTypeByID fails.
   Ice::FuncSigType UndefinedFuncSigType;
   // The block parser currently being applied. Used for error reporting.
   BlockParserBaseClass *BlockParser = nullptr;
+  // Defines if a module block has already been parsed.
+  bool ParsedModuleBlock = false;
 
   bool ParseBlock(unsigned BlockID) override;
 
   // Gets extended type associated with the given index, assuming the extended
   // type is of the WantedKind. Generates error message if corresponding
   // extended type of WantedKind can't be found, and returns nullptr.
   ExtendedType *getTypeByIDAsKind(NaClBcIndexSize_t ID,
                                   ExtendedType::TypeKind WantedKind) {
     ExtendedType *Ty = nullptr;
     if (ID < TypeIDValues.size()) {
@@ skipping 2826 matching lines @@
     return;
   }
   default:
     BlockParserBaseClass::ProcessRecord();
     return;
   }
 }
 
 bool TopLevelParser::ParseBlock(unsigned BlockID) {
   if (BlockID == naclbitc::MODULE_BLOCK_ID) {
+    if (ParsedModuleBlock)
+      Fatal("Input can't contain more than one module");
     ModuleParser Parser(BlockID, this);
-    return Parser.ParseThisBlock();
+    bool ParseFailed = Parser.ParseThisBlock();
+    ParsedModuleBlock = true;
+    return ParseFailed;
   }
   // Generate error message by using default block implementation.
   BlockParserBaseClass Parser(BlockID, this);
   return Parser.ParseThisBlock();
 }
 
 } // end of anonymous namespace
 
 namespace Ice {
 
 void PNaClTranslator::translateBuffer(const std::string &IRFilename,
                                       MemoryBuffer *MemBuf) {
   std::unique_ptr<MemoryObject> MemObj(getNonStreamedMemoryObject(
       reinterpret_cast<const unsigned char *>(MemBuf->getBufferStart()),
       reinterpret_cast<const unsigned char *>(MemBuf->getBufferEnd())));
   translate(IRFilename, std::move(MemObj));
 }
 
 void PNaClTranslator::translate(const std::string &IRFilename,
                                 std::unique_ptr<MemoryObject> &&MemObj) {
   // On error, we report_fatal_error to avoid destroying the MemObj. That may
   // still be in use by IceBrowserCompileServer. Otherwise, we need to change
   // the MemObj to be ref-counted, or have a wrapper, or simply leak. We also
   // need a hook to tell the IceBrowserCompileServer to unblock its
   // QueueStreamer.
   // https://code.google.com/p/nativeclient/issues/detail?id=4163
-  Ostream &ErrStream = getContext()->getStrError();
   // Read header and verify it is good.
   NaClBitcodeHeader Header;
   if (Header.Read(MemObj.get())) {
     llvm::report_fatal_error("Invalid PNaCl bitcode header");
   }
   if (!Header.IsSupported()) {
-    ErrStream << Header.Unsupported();
+    getContext()->getStrError() << Header.Unsupported();
     if (!Header.IsReadable()) {
       llvm::report_fatal_error("Invalid PNaCl bitcode header");
     }
   }
 
   // Create a bitstream reader to read the bitcode file.
   NaClBitstreamReader InputStreamFile(MemObj.release(), Header);
   NaClBitstreamCursor InputStream(InputStreamFile);
 
   TopLevelParser Parser(*this, InputStream, ErrorStatus);
-  int TopLevelBlocks = 0;
   while (!InputStream.AtEndOfStream()) {
     if (Parser.Parse()) {
       ErrorStatus.assign(EC_Bitcode);
       return;
     }
-    ++TopLevelBlocks;
   }
 
-  if (TopLevelBlocks != 1) {
-    ErrStream << IRFilename
-              << ": Contains more than one module. Found: " << TopLevelBlocks
-              << "\n";
-    llvm::report_fatal_error("Bitcode has more than one module");
+  if (!Parser.parsedModuleBlock()) {
+    std::string Buffer;
+    raw_string_ostream StrBuf(Buffer);
+    StrBuf << IRFilename << ": Does not contain a module!";
+    llvm::report_fatal_error(StrBuf.str());
   }
   if (InputStreamFile.getBitcodeBytes().getExtent() % 4 != 0) {
-    ErrStream
-        << IRFilename
-        << ": Bitcode stream should be a multiple of 4 bytes in length.\n";
     llvm::report_fatal_error("Bitcode stream should be a multiple of 4 bytes");
   }
 }
 
 } // end of namespace Ice