C++ const_global_iterator::hasDLLExportLinkage方法代码示例

//.........这里部分代码省略.........
      }
      Stubs.clear();
      OutStreamer.AddBlankLine();
    }

    // Funny Darwin hack: This flag tells the linker that no global symbols
    // contain code that falls through to other global symbols (e.g. the obvious
    // implementation of multiple entry points).  If this doesn't occur, the
    // linker can safely perform dead code stripping.  Since LLVM never
    // generates code that does this, it is always safe to set.
    OutStreamer.EmitAssemblerFlag(MCAF_SubsectionsViaSymbols);
  }

  if (Subtarget->isTargetWindows() && !Subtarget->isTargetCygMing() &&
      MMI->usesVAFloatArgument()) {
    StringRef SymbolName = Subtarget->is64Bit() ? "_fltused" : "__fltused";
    MCSymbol *S = MMI->getContext().GetOrCreateSymbol(SymbolName);
    OutStreamer.EmitSymbolAttribute(S, MCSA_Global);
  }

  if (Subtarget->isTargetCOFF() && !Subtarget->isTargetEnvMacho()) {
    X86COFFMachineModuleInfo &COFFMMI =
      MMI->getObjFileInfo<X86COFFMachineModuleInfo>();

    // Emit type information for external functions
    typedef X86COFFMachineModuleInfo::externals_iterator externals_iterator;
    for (externals_iterator I = COFFMMI.externals_begin(),
                            E = COFFMMI.externals_end();
                            I != E; ++I) {
      OutStreamer.BeginCOFFSymbolDef(CurrentFnSym);
      OutStreamer.EmitCOFFSymbolStorageClass(COFF::IMAGE_SYM_CLASS_EXTERNAL);
      OutStreamer.EmitCOFFSymbolType(COFF::IMAGE_SYM_DTYPE_FUNCTION
                                               << COFF::SCT_COMPLEX_TYPE_SHIFT);
      OutStreamer.EndCOFFSymbolDef();
    }

    // Necessary for dllexport support
    std::vector<const MCSymbol*> DLLExportedFns, DLLExportedGlobals;

    const TargetLoweringObjectFileCOFF &TLOFCOFF =
      static_cast<const TargetLoweringObjectFileCOFF&>(getObjFileLowering());

    for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I)
      if (I->hasDLLExportLinkage())
        DLLExportedFns.push_back(Mang->getSymbol(I));

    for (Module::const_global_iterator I = M.global_begin(),
           E = M.global_end(); I != E; ++I)
      if (I->hasDLLExportLinkage())
        DLLExportedGlobals.push_back(Mang->getSymbol(I));

    // Output linker support code for dllexported globals on windows.
    if (!DLLExportedGlobals.empty() || !DLLExportedFns.empty()) {
      OutStreamer.SwitchSection(TLOFCOFF.getDrectveSection());
      SmallString<128> name;
      for (unsigned i = 0, e = DLLExportedGlobals.size(); i != e; ++i) {
        if (Subtarget->isTargetWindows())
          name = " /EXPORT:";
        else
          name = " -export:";
        name += DLLExportedGlobals[i]->getName();
        if (Subtarget->isTargetWindows())
          name += ",DATA";
        else
        name += ",data";
        OutStreamer.EmitBytes(name);
      }

      for (unsigned i = 0, e = DLLExportedFns.size(); i != e; ++i) {
        if (Subtarget->isTargetWindows())
          name = " /EXPORT:";
        else
          name = " -export:";
        name += DLLExportedFns[i]->getName();
        OutStreamer.EmitBytes(name);
      }
    }
  }

  if (Subtarget->isTargetELF()) {
    const TargetLoweringObjectFileELF &TLOFELF =
      static_cast<const TargetLoweringObjectFileELF &>(getObjFileLowering());

    MachineModuleInfoELF &MMIELF = MMI->getObjFileInfo<MachineModuleInfoELF>();

    // Output stubs for external and common global variables.
    MachineModuleInfoELF::SymbolListTy Stubs = MMIELF.GetGVStubList();
    if (!Stubs.empty()) {
      OutStreamer.SwitchSection(TLOFELF.getDataRelSection());
      const DataLayout *TD = TM.getDataLayout();

      for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
        OutStreamer.EmitLabel(Stubs[i].first);
        OutStreamer.EmitSymbolValue(Stubs[i].second.getPointer(),
                                    TD->getPointerSize());
      }
      Stubs.clear();
    }
  }
}