C++ SymbolListTy::clear方法代码示例

bool PPCDarwinAsmPrinter::doFinalization(Module &M) {
  bool isPPC64 = TM.getTargetData()->getPointerSizeInBits() == 64;

  // Darwin/PPC always uses mach-o.
  const TargetLoweringObjectFileMachO &TLOFMacho = 
    static_cast<const TargetLoweringObjectFileMachO &>(getObjFileLowering());
  MachineModuleInfoMachO &MMIMacho =
    MMI->getObjFileInfo<MachineModuleInfoMachO>();
  
  MachineModuleInfoMachO::SymbolListTy Stubs = MMIMacho.GetFnStubList();
  if (!Stubs.empty())
    EmitFunctionStubs(Stubs);

  if (MAI->doesSupportExceptionHandling() && MMI) {
    // Add the (possibly multiple) personalities to the set of global values.
    // Only referenced functions get into the Personalities list.
    const std::vector<const Function*> &Personalities = MMI->getPersonalities();
    for (std::vector<const Function*>::const_iterator I = Personalities.begin(),
         E = Personalities.end(); I != E; ++I) {
      if (*I) {
        MCSymbol *NLPSym = GetSymbolWithGlobalValueBase(*I, "$non_lazy_ptr");
        MachineModuleInfoImpl::StubValueTy &StubSym =
          MMIMacho.getGVStubEntry(NLPSym);
        StubSym = MachineModuleInfoImpl::StubValueTy(Mang->getSymbol(*I), true);
      }
    }
  }

  // Output stubs for dynamically-linked functions.
  Stubs = MMIMacho.GetGVStubList();
  
  // Output macho stubs for external and common global variables.
  if (!Stubs.empty()) {
    // Switch with ".non_lazy_symbol_pointer" directive.
    OutStreamer.SwitchSection(TLOFMacho.getNonLazySymbolPointerSection());
    EmitAlignment(isPPC64 ? 3 : 2);
    
    for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
      // L_foo$stub:
      OutStreamer.EmitLabel(Stubs[i].first);
      //   .indirect_symbol _foo
      MachineModuleInfoImpl::StubValueTy &MCSym = Stubs[i].second;
      OutStreamer.EmitSymbolAttribute(MCSym.getPointer(), MCSA_IndirectSymbol);

      if (MCSym.getInt())
        // External to current translation unit.
        OutStreamer.EmitIntValue(0, isPPC64 ? 8 : 4/*size*/, 0/*addrspace*/);
      else
        // Internal to current translation unit.
        //
        // When we place the LSDA into the TEXT section, the type info pointers
        // need to be indirect and pc-rel. We accomplish this by using NLPs.
        // However, sometimes the types are local to the file. So we need to
        // fill in the value for the NLP in those cases.
        OutStreamer.EmitValue(MCSymbolRefExpr::Create(MCSym.getPointer(),
                                                      OutContext),
                              isPPC64 ? 8 : 4/*size*/, 0/*addrspace*/);
    }

    Stubs.clear();
    OutStreamer.AddBlankLine();
  }

  Stubs = MMIMacho.GetHiddenGVStubList();
  if (!Stubs.empty()) {
    OutStreamer.SwitchSection(getObjFileLowering().getDataSection());
    EmitAlignment(isPPC64 ? 3 : 2);
    
    for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
      // L_foo$stub:
      OutStreamer.EmitLabel(Stubs[i].first);
      //   .long _foo
      OutStreamer.EmitValue(MCSymbolRefExpr::
                            Create(Stubs[i].second.getPointer(),
                                   OutContext),
                            isPPC64 ? 8 : 4/*size*/, 0/*addrspace*/);
    }

    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);

  return AsmPrinter::doFinalization(M);
}

void X86AsmPrinter::EmitEndOfAsmFile(Module &M) {
  const Triple &TT = TM.getTargetTriple();

  if (TT.isOSBinFormatMachO()) {
    // All darwin targets use mach-o.
    MachineModuleInfoMachO &MMIMacho =
        MMI->getObjFileInfo<MachineModuleInfoMachO>();

    // Output stubs for dynamically-linked functions.
    MachineModuleInfoMachO::SymbolListTy Stubs;

    Stubs = MMIMacho.GetFnStubList();
    if (!Stubs.empty()) {
      MCSection *TheSection = OutContext.getMachOSection(
          "__IMPORT", "__jump_table",
          MachO::S_SYMBOL_STUBS | MachO::S_ATTR_SELF_MODIFYING_CODE |
              MachO::S_ATTR_PURE_INSTRUCTIONS,
          5, SectionKind::getMetadata());
      OutStreamer->SwitchSection(TheSection);

      for (const auto &Stub : Stubs) {
        // L_foo$stub:
        OutStreamer->EmitLabel(Stub.first);
        //   .indirect_symbol _foo
        OutStreamer->EmitSymbolAttribute(Stub.second.getPointer(),
                                         MCSA_IndirectSymbol);
        // hlt; hlt; hlt; hlt; hlt     hlt = 0xf4.
        const char HltInsts[] = "\xf4\xf4\xf4\xf4\xf4";
        OutStreamer->EmitBytes(StringRef(HltInsts, 5));
      }

      Stubs.clear();
      OutStreamer->AddBlankLine();
    }

    // Output stubs for external and common global variables.
    Stubs = MMIMacho.GetGVStubList();
    if (!Stubs.empty()) {
      MCSection *TheSection = OutContext.getMachOSection(
          "__IMPORT", "__pointers", MachO::S_NON_LAZY_SYMBOL_POINTERS,
          SectionKind::getMetadata());
      OutStreamer->SwitchSection(TheSection);

      for (auto &Stub : Stubs)
        emitNonLazySymbolPointer(*OutStreamer, Stub.first, Stub.second);

      Stubs.clear();
      OutStreamer->AddBlankLine();
    }

    Stubs = MMIMacho.GetHiddenGVStubList();
    if (!Stubs.empty()) {
      MCSection *TheSection = OutContext.getMachOSection(
          "__IMPORT", "__pointers", MachO::S_NON_LAZY_SYMBOL_POINTERS,
          SectionKind::getMetadata());
      OutStreamer->SwitchSection(TheSection);

      for (auto &Stub : Stubs)
        emitNonLazySymbolPointer(*OutStreamer, Stub.first, Stub.second);

      Stubs.clear();
      OutStreamer->AddBlankLine();
    }

    SM.serializeToStackMapSection();
    FM.serializeToFaultMapSection();

    // 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 (TT.isKnownWindowsMSVCEnvironment() && MMI->usesVAFloatArgument()) {
    StringRef SymbolName =
        (TT.getArch() == Triple::x86_64) ? "_fltused" : "__fltused";
    MCSymbol *S = MMI->getContext().getOrCreateSymbol(SymbolName);
    OutStreamer->EmitSymbolAttribute(S, MCSA_Global);
  }

  if (TT.isOSBinFormatCOFF()) {
    const TargetLoweringObjectFileCOFF &TLOFCOFF =
        static_cast<const TargetLoweringObjectFileCOFF&>(getObjFileLowering());

    std::string Flags;
    raw_string_ostream FlagsOS(Flags);

    for (const auto &Function : M)
      TLOFCOFF.emitLinkerFlagsForGlobal(FlagsOS, &Function, *Mang);
    for (const auto &Global : M.globals())
      TLOFCOFF.emitLinkerFlagsForGlobal(FlagsOS, &Global, *Mang);
    for (const auto &Alias : M.aliases())
      TLOFCOFF.emitLinkerFlagsForGlobal(FlagsOS, &Alias, *Mang);

    FlagsOS.flush();

    // Output collected flags.
    if (!Flags.empty()) {
//.........这里部分代码省略.........

void Cse523AsmPrinter::EmitEndOfAsmFile(Module &M) {
    if (Subtarget->isTargetMacho()) {
        // All darwin targets use mach-o.
        MachineModuleInfoMachO &MMIMacho =
            MMI->getObjFileInfo<MachineModuleInfoMachO>();

        // Output stubs for dynamically-linked functions.
        MachineModuleInfoMachO::SymbolListTy Stubs;

        Stubs = MMIMacho.GetFnStubList();
        if (!Stubs.empty()) {
            const MCSection *TheSection =
                OutContext.getMachOSection("__IMPORT", "__jump_table",
                        MCSectionMachO::S_SYMBOL_STUBS |
                        MCSectionMachO::S_ATTR_SELF_MODIFYING_CODE |
                        MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
                        5, SectionKind::getMetadata());
            OutStreamer.SwitchSection(TheSection);

            for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
                // L_foo$stub:
                OutStreamer.EmitLabel(Stubs[i].first);
                //   .indirect_symbol _foo
                OutStreamer.EmitSymbolAttribute(Stubs[i].second.getPointer(),
                        MCSA_IndirectSymbol);
                // hlt; hlt; hlt; hlt; hlt     hlt = 0xf4.
                const char HltInsts[] = "\xf4\xf4\xf4\xf4\xf4";
                OutStreamer.EmitBytes(StringRef(HltInsts, 5));
            }

            Stubs.clear();
            OutStreamer.AddBlankLine();
        }

        // Output stubs for external and common global variables.
        Stubs = MMIMacho.GetGVStubList();
        if (!Stubs.empty()) {
            const MCSection *TheSection =
                OutContext.getMachOSection("__IMPORT", "__pointers",
                        MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS,
                        SectionKind::getMetadata());
            OutStreamer.SwitchSection(TheSection);

            for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
                // L_foo$non_lazy_ptr:
                OutStreamer.EmitLabel(Stubs[i].first);
                // .indirect_symbol _foo
                MachineModuleInfoImpl::StubValueTy &MCSym = Stubs[i].second;
                OutStreamer.EmitSymbolAttribute(MCSym.getPointer(),
                        MCSA_IndirectSymbol);
                // .long 0
                if (MCSym.getInt())
                    // External to current translation unit.
                    OutStreamer.EmitIntValue(0, 4/*size*/);
                else
                    // Internal to current translation unit.
                    //
                    // When we place the LSDA into the TEXT section, the type info
                    // pointers need to be indirect and pc-rel. We accomplish this by
                    // using NLPs.  However, sometimes the types are local to the file. So
                    // we need to fill in the value for the NLP in those cases.
                    OutStreamer.EmitValue(MCSymbolRefExpr::Create(MCSym.getPointer(),
                                OutContext), 4/*size*/);
            }
            Stubs.clear();
            OutStreamer.AddBlankLine();
        }

        Stubs = MMIMacho.GetHiddenGVStubList();
        if (!Stubs.empty()) {
            OutStreamer.SwitchSection(getObjFileLowering().getDataSection());
            EmitAlignment(2);

            for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
                // L_foo$non_lazy_ptr:
                OutStreamer.EmitLabel(Stubs[i].first);
                // .long _foo
                OutStreamer.EmitValue(MCSymbolRefExpr::
                        Create(Stubs[i].second.getPointer(),
                            OutContext), 4/*size*/);
            }
            Stubs.clear();
            OutStreamer.AddBlankLine();
        }

        SM.serializeToStackMapSection();

        // 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);
//.........这里部分代码省略.........

void X86AsmPrinter::EmitEndOfAsmFile(Module &M) {
  if (Subtarget->isTargetMacho()) {
    // All darwin targets use mach-o.
    MachineModuleInfoMachO &MMIMacho =
      MMI->getObjFileInfo<MachineModuleInfoMachO>();

    // Output stubs for dynamically-linked functions.
    MachineModuleInfoMachO::SymbolListTy Stubs;

    Stubs = MMIMacho.GetFnStubList();
    if (!Stubs.empty()) {
      const MCSection *TheSection =
        OutContext.getMachOSection("__IMPORT", "__jump_table",
                                   MachO::S_SYMBOL_STUBS |
                                   MachO::S_ATTR_SELF_MODIFYING_CODE |
                                   MachO::S_ATTR_PURE_INSTRUCTIONS,
                                   5, SectionKind::getMetadata());
      OutStreamer.SwitchSection(TheSection);

      for (const auto &Stub : Stubs) {
        // L_foo$stub:
        OutStreamer.EmitLabel(Stub.first);
        //   .indirect_symbol _foo
        OutStreamer.EmitSymbolAttribute(Stub.second.getPointer(),
                                        MCSA_IndirectSymbol);
        // hlt; hlt; hlt; hlt; hlt     hlt = 0xf4.
        const char HltInsts[] = "\xf4\xf4\xf4\xf4\xf4";
        OutStreamer.EmitBytes(StringRef(HltInsts, 5));
      }

      Stubs.clear();
      OutStreamer.AddBlankLine();
    }

    // Output stubs for external and common global variables.
    Stubs = MMIMacho.GetGVStubList();
    if (!Stubs.empty()) {
      const MCSection *TheSection =
        OutContext.getMachOSection("__IMPORT", "__pointers",
                                   MachO::S_NON_LAZY_SYMBOL_POINTERS,
                                   SectionKind::getMetadata());
      OutStreamer.SwitchSection(TheSection);

      for (auto &Stub : Stubs)
        emitNonLazySymbolPointer(OutStreamer, Stub.first, Stub.second);

      Stubs.clear();
      OutStreamer.AddBlankLine();
    }

    Stubs = MMIMacho.GetHiddenGVStubList();
    if (!Stubs.empty()) {
      const MCSection *TheSection =
        OutContext.getMachOSection("__IMPORT", "__pointers",
                                   MachO::S_NON_LAZY_SYMBOL_POINTERS,
                                   SectionKind::getMetadata());
      OutStreamer.SwitchSection(TheSection);

      for (auto &Stub : Stubs)
        emitNonLazySymbolPointer(OutStreamer, Stub.first, Stub.second);

      Stubs.clear();
      OutStreamer.AddBlankLine();
    }

    SM.serializeToStackMapSection();

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

  if (Subtarget->isTargetCOFF()) {
    // Necessary for dllexport support
    std::vector<const MCSymbol*> DLLExportedFns, DLLExportedGlobals;

    for (const auto &Function : M)
      if (Function.hasDLLExportStorageClass())
        DLLExportedFns.push_back(getSymbol(&Function));

    for (const auto &Global : M.globals())
      if (Global.hasDLLExportStorageClass())
        DLLExportedGlobals.push_back(getSymbol(&Global));

    for (const auto &Alias : M.aliases()) {
      if (!Alias.hasDLLExportStorageClass())
        continue;

      if (Alias.getType()->getElementType()->isFunctionTy())
        DLLExportedFns.push_back(getSymbol(&Alias));
      else
//.........这里部分代码省略.........