C++ MCStreamer::EmitLinkerOptions方法代码示例

void TargetLoweringObjectFileMachO::emitModuleMetadata(
    MCStreamer &Streamer, Module &M, const TargetMachine &TM) const {
  // Emit the linker options if present.
  if (auto *LinkerOptions = M.getNamedMetadata("llvm.linker.options")) {
    for (const auto &Option : LinkerOptions->operands()) {
      SmallVector<std::string, 4> StrOptions;
      for (const auto &Piece : cast<MDNode>(Option)->operands())
        StrOptions.push_back(cast<MDString>(Piece)->getString());
      Streamer.EmitLinkerOptions(StrOptions);
    }
  }

  unsigned VersionVal = 0;
  unsigned ImageInfoFlags = 0;
  StringRef SectionVal;

  GetObjCImageInfo(M, VersionVal, ImageInfoFlags, SectionVal);

  // The section is mandatory. If we don't have it, then we don't have GC info.
  if (SectionVal.empty())
    return;

  StringRef Segment, Section;
  unsigned TAA = 0, StubSize = 0;
  bool TAAParsed;
  std::string ErrorCode =
    MCSectionMachO::ParseSectionSpecifier(SectionVal, Segment, Section,
                                          TAA, TAAParsed, StubSize);
  if (!ErrorCode.empty())
    // If invalid, report the error with report_fatal_error.
    report_fatal_error("Invalid section specifier '" + Section + "': " +
                       ErrorCode + ".");

  // Get the section.
  MCSectionMachO *S = getContext().getMachOSection(
      Segment, Section, TAA, StubSize, SectionKind::getData());
  Streamer.SwitchSection(S);
  Streamer.EmitLabel(getContext().
                     getOrCreateSymbol(StringRef("L_OBJC_IMAGE_INFO")));
  Streamer.EmitIntValue(VersionVal, 4);
  Streamer.EmitIntValue(ImageInfoFlags, 4);
  Streamer.AddBlankLine();
}

/// emitModuleFlags - Perform code emission for module flags.
void TargetLoweringObjectFileMachO::
emitModuleFlags(MCStreamer &Streamer,
                ArrayRef<Module::ModuleFlagEntry> ModuleFlags,
                Mangler &Mang, const TargetMachine &TM) const {
  unsigned VersionVal = 0;
  unsigned ImageInfoFlags = 0;
  MDNode *LinkerOptions = nullptr;
  StringRef SectionVal;

  for (ArrayRef<Module::ModuleFlagEntry>::iterator
         i = ModuleFlags.begin(), e = ModuleFlags.end(); i != e; ++i) {
    const Module::ModuleFlagEntry &MFE = *i;

    // Ignore flags with 'Require' behavior.
    if (MFE.Behavior == Module::Require)
      continue;

    StringRef Key = MFE.Key->getString();
    Value *Val = MFE.Val;

    if (Key == "Objective-C Image Info Version") {
      VersionVal = cast<ConstantInt>(Val)->getZExtValue();
    } else if (Key == "Objective-C Garbage Collection" ||
               Key == "Objective-C GC Only" ||
               Key == "Objective-C Is Simulated") {
      ImageInfoFlags |= cast<ConstantInt>(Val)->getZExtValue();
    } else if (Key == "Objective-C Image Info Section") {
      SectionVal = cast<MDString>(Val)->getString();
    } else if (Key == "Linker Options") {
      LinkerOptions = cast<MDNode>(Val);
    }
  }

  // Emit the linker options if present.
  if (LinkerOptions) {
    for (unsigned i = 0, e = LinkerOptions->getNumOperands(); i != e; ++i) {
      MDNode *MDOptions = cast<MDNode>(LinkerOptions->getOperand(i));
      SmallVector<std::string, 4> StrOptions;

      // Convert to strings.
      for (unsigned ii = 0, ie = MDOptions->getNumOperands(); ii != ie; ++ii) {
        MDString *MDOption = cast<MDString>(MDOptions->getOperand(ii));
        StrOptions.push_back(MDOption->getString());
      }

      Streamer.EmitLinkerOptions(StrOptions);
    }
  }

  // The section is mandatory. If we don't have it, then we don't have GC info.
  if (SectionVal.empty()) return;

  StringRef Segment, Section;
  unsigned TAA = 0, StubSize = 0;
  bool TAAParsed;
  std::string ErrorCode =
    MCSectionMachO::ParseSectionSpecifier(SectionVal, Segment, Section,
                                          TAA, TAAParsed, StubSize);
  if (!ErrorCode.empty())
    // If invalid, report the error with report_fatal_error.
    report_fatal_error("Invalid section specifier '" + Section + "': " +
                       ErrorCode + ".");

  // Get the section.
  const MCSectionMachO *S =
    getContext().getMachOSection(Segment, Section, TAA, StubSize,
                                 SectionKind::getDataNoRel());
  Streamer.SwitchSection(S);
  Streamer.EmitLabel(getContext().
                     GetOrCreateSymbol(StringRef("L_OBJC_IMAGE_INFO")));
  Streamer.EmitIntValue(VersionVal, 4);
  Streamer.EmitIntValue(ImageInfoFlags, 4);
  Streamer.AddBlankLine();
}

/// emitModuleFlags - Perform code emission for module flags.
void TargetLoweringObjectFileMachO::emitModuleFlags(
    MCStreamer &Streamer, ArrayRef<Module::ModuleFlagEntry> ModuleFlags,
    const TargetMachine &TM) const {
  unsigned VersionVal = 0;
  unsigned ImageInfoFlags = 0;
  MDNode *LinkerOptions = nullptr;
  StringRef SectionVal;

  for (const auto &MFE : ModuleFlags) {
    // Ignore flags with 'Require' behavior.
    if (MFE.Behavior == Module::Require)
      continue;

    StringRef Key = MFE.Key->getString();
    Metadata *Val = MFE.Val;

    if (Key == "Objective-C Image Info Version") {
      VersionVal = mdconst::extract<ConstantInt>(Val)->getZExtValue();
    } else if (Key == "Objective-C Garbage Collection" ||
               Key == "Objective-C GC Only" ||
               Key == "Objective-C Is Simulated" ||
               Key == "Objective-C Class Properties" ||
               Key == "Objective-C Image Swift Version") {
      ImageInfoFlags |= mdconst::extract<ConstantInt>(Val)->getZExtValue();
    } else if (Key == "Objective-C Image Info Section") {
      SectionVal = cast<MDString>(Val)->getString();
    } else if (Key == "Linker Options") {
      LinkerOptions = cast<MDNode>(Val);
    }
  }

  // Emit the linker options if present.
  if (LinkerOptions) {
    for (const auto &Option : LinkerOptions->operands()) {
      SmallVector<std::string, 4> StrOptions;
      for (const auto &Piece : cast<MDNode>(Option)->operands())
        StrOptions.push_back(cast<MDString>(Piece)->getString());
      Streamer.EmitLinkerOptions(StrOptions);
    }
  }

  // The section is mandatory. If we don't have it, then we don't have GC info.
  if (SectionVal.empty()) return;

  StringRef Segment, Section;
  unsigned TAA = 0, StubSize = 0;
  bool TAAParsed;
  std::string ErrorCode =
    MCSectionMachO::ParseSectionSpecifier(SectionVal, Segment, Section,
                                          TAA, TAAParsed, StubSize);
  if (!ErrorCode.empty())
    // If invalid, report the error with report_fatal_error.
    report_fatal_error("Invalid section specifier '" + Section + "': " +
                       ErrorCode + ".");

  // Get the section.
  MCSectionMachO *S = getContext().getMachOSection(
      Segment, Section, TAA, StubSize, SectionKind::getData());
  Streamer.SwitchSection(S);
  Streamer.EmitLabel(getContext().
                     getOrCreateSymbol(StringRef("L_OBJC_IMAGE_INFO")));
  Streamer.EmitIntValue(VersionVal, 4);
  Streamer.EmitIntValue(ImageInfoFlags, 4);
  Streamer.AddBlankLine();
}