Subzero: Add basic ELFObjectWriter (text section, symtab, strtab, headers)

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.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements the PNaCl bitcode file to Ice, to machine code
@@ skipping 164 matching lines @@
         ErrorStatus(ErrorStatus), NumErrors(0), NumFunctionIds(0),
         NumFunctionBlocks(0) {
     Mod->setDataLayout(PNaClDataLayout);
     setErrStream(Translator.getContext()->getStrDump());
   }
 
   ~TopLevelParser() override {}
 
   Ice::Translator &getTranslator() { return Translator; }
 
+  // Need some way to access the Ice::ELFObjectWriter.
+
   // Generates error with given Message. Always returns true.
   bool Error(const std::string &Message) override {
     ErrorStatus = true;
     ++NumErrors;
     NaClBitcodeParser::Error(Message);
     if (!AllowErrorRecovery)
       report_fatal_error("Unable to continue");
     return true;
   }
 
@@ skipping 2677 matching lines @@
 
   if (TopLevelBlocks != 1) {
     errs() << IRFilename
            << ": Contains more than one module. Found: " << TopLevelBlocks
            << "\n";
     ErrorStatus = true;
   }
 }
 
 } // end of namespace Ice