text: //===-- llvm/MC/MCObjectFileInfo.h - Object File Info -----------*- C++ -*-===//
  //
  //                     The LLVM Compiler Infrastructure
  //
  // This file is distributed under the University of Illinois Open Source
  // License. See LICENSE.TXT for details.
  //
  //===----------------------------------------------------------------------===//
  //
  // This file describes common object file formats.
  //
  //===----------------------------------------------------------------------===//
  
  #ifndef LLVM_MC_MCBJECTFILEINFO_H
  #define LLVM_MC_MCBJECTFILEINFO_H
  
  #include "llvm/MC/MCCodeGenInfo.h"
  #include "llvm/ADT/StringRef.h"
  #include "llvm/MC/SectionKind.h"
  
  namespace llvm {
  class MCContext;
  class MCSection;
  class Triple;
    
  class MCObjectFileInfo {  
  protected:
    /// CommDirectiveSupportsAlignment - True if .comm supports alignment.  This
    /// is a hack for as long as we support 10.4 Tiger, whose assembler doesn't
    /// support alignment on comm.
    bool CommDirectiveSupportsAlignment;
    
    /// SupportsWeakEmptyEHFrame - True if target object file supports a
    /// weak_definition of constant 0 for an omitted EH frame.
    bool SupportsWeakOmittedEHFrame;
    
    /// IsFunctionEHFrameSymbolPrivate - This flag is set to true if the
    /// "EH_frame" symbol for EH information should be an assembler temporary (aka
    /// private linkage, aka an L or .L label) or false if it should be a normal
    /// non-.globl label.  This defaults to true.
    bool IsFunctionEHFrameSymbolPrivate;
  
    /// PersonalityEncoding, LSDAEncoding, FDEEncoding, TTypeEncoding - Some
    /// encoding values for EH.
    unsigned PersonalityEncoding;
    unsigned LSDAEncoding;
    unsigned FDEEncoding;
    unsigned FDECFIEncoding;
    unsigned TTypeEncoding;
  
    /// TextSection - Section directive for standard text.
    ///
    const MCSection *TextSection;
    
    /// DataSection - Section directive for standard data.
    ///
    const MCSection *DataSection;
    
    /// BSSSection - Section that is default initialized to zero.
    const MCSection *BSSSection;
    
    /// ReadOnlySection - Section that is readonly and can contain arbitrary
    /// initialized data.  Targets are not required to have a readonly section.
    /// If they don't, various bits of code will fall back to using the data
    /// section for constants.
    const MCSection *ReadOnlySection;
    
    /// StaticCtorSection - This section contains the static constructor pointer
    /// list.
    const MCSection *StaticCtorSection;
  
    /// StaticDtorSection - This section contains the static destructor pointer
    /// list.
    const MCSection *StaticDtorSection;
    
    /// LSDASection - If exception handling is supported by the target, this is
    /// the section the Language Specific Data Area information is emitted to.
    const MCSection *LSDASection;
  
    /// CompactUnwindSection - If exception handling is supported by the target
    /// and the target can support a compact representation of the CIE and FDE,
    /// this is the section to emit them into.
    const MCSection *CompactUnwindSection;
  
    // Dwarf sections for debug info.  If a target supports debug info, these must
    // be set.
    const MCSection *DwarfAbbrevSection;
    const MCSection *DwarfInfoSection;
    const MCSection *DwarfLineSection;
    const MCSection *DwarfFrameSection;
    const MCSection *DwarfPubNamesSection;
    const MCSection *DwarfPubTypesSection;
    const MCSection *DwarfDebugInlineSection;
    const MCSection *DwarfStrSection;
    const MCSection *DwarfLocSection;
    const MCSection *DwarfARangesSection;
    const MCSection *DwarfRangesSection;
    const MCSection *DwarfMacroInfoSection;
  
    // Extra TLS Variable Data section.  If the target needs to put additional
    // information for a TLS variable, it'll go here.
    const MCSection *TLSExtraDataSection;
    
    /// TLSDataSection - Section directive for Thread Local data.
    /// ELF and MachO only.
    const MCSection *TLSDataSection;        // Defaults to ".tdata".
  
    /// TLSBSSSection - Section directive for Thread Local uninitialized data.
    /// Null if this target doesn't support a BSS section.
    /// ELF and MachO only.
    const MCSection *TLSBSSSection;         // Defaults to ".tbss".
  
  
    /// EHFrameSection - EH frame section. It is initialized on demand so it
    /// can be overwritten (with uniquing).
    const MCSection *EHFrameSection;
  
    /// ELF specific sections.
    ///
    const MCSection *DataRelSection;
    const MCSection *DataRelLocalSection;
    const MCSection *DataRelROSection;
    const MCSection *DataRelROLocalSection;
    const MCSection *MergeableConst4Section;
    const MCSection *MergeableConst8Section;
    const MCSection *MergeableConst16Section;
  
    /// MachO specific sections.
    ///
  
    /// TLSTLVSection - Section for thread local structure information.
    /// Contains the source code name of the variable, visibility and a pointer
    /// to the initial value (.tdata or .tbss).
    const MCSection *TLSTLVSection;         // Defaults to ".tlv".
    
    /// TLSThreadInitSection - Section for thread local data initialization
    /// functions.
    const MCSection *TLSThreadInitSection;  // Defaults to ".thread_init_func".
    
    const MCSection *CStringSection;
    const MCSection *UStringSection;
    const MCSection *TextCoalSection;
    const MCSection *ConstTextCoalSection;
    const MCSection *ConstDataSection;
    const MCSection *DataCoalSection;
    const MCSection *DataCommonSection;
    const MCSection *DataBSSSection;
    const MCSection *FourByteConstantSection;
    const MCSection *EightByteConstantSection;
    const MCSection *SixteenByteConstantSection;
    const MCSection *LazySymbolPointerSection;
    const MCSection *NonLazySymbolPointerSection;
  
    /// COFF specific sections.
    ///
    const MCSection *DrectveSection;
    const MCSection *PDataSection;
    const MCSection *XDataSection;
    
  public:
    void InitMCObjectFileInfo(StringRef TT, Reloc::Model RM, CodeModel::Model CM,
                              MCContext &ctx);
    
    bool isFunctionEHFrameSymbolPrivate() const {
      return IsFunctionEHFrameSymbolPrivate;
    }
    bool getSupportsWeakOmittedEHFrame() const {
      return SupportsWeakOmittedEHFrame;
    }
    bool getCommDirectiveSupportsAlignment() const {
      return CommDirectiveSupportsAlignment;
    }
  
    unsigned getPersonalityEncoding() const { return PersonalityEncoding; }
    unsigned getLSDAEncoding() const { return LSDAEncoding; }
    unsigned getFDEEncoding(bool CFI) const {
      return CFI ? FDECFIEncoding : FDEEncoding;
    }
    unsigned getTTypeEncoding() const { return TTypeEncoding; }
  
    const MCSection *getTextSection() const { return TextSection; }
    const MCSection *getDataSection() const { return DataSection; }
    const MCSection *getBSSSection() const { return BSSSection; }
    const MCSection *getStaticCtorSection() const { return StaticCtorSection; }
    const MCSection *getStaticDtorSection() const { return StaticDtorSection; }
    const MCSection *getLSDASection() const { return LSDASection; }
    const MCSection *getCompactUnwindSection() const{
      return CompactUnwindSection;
    }
    const MCSection *getDwarfAbbrevSection() const { return DwarfAbbrevSection; }
    const MCSection *getDwarfInfoSection() const { return DwarfInfoSection; }
    const MCSection *getDwarfLineSection() const { return DwarfLineSection; }
    const MCSection *getDwarfFrameSection() const { return DwarfFrameSection; }
    const MCSection *getDwarfPubNamesSection() const{return DwarfPubNamesSection;}
    const MCSection *getDwarfPubTypesSection() const{return DwarfPubTypesSection;}
    const MCSection *getDwarfDebugInlineSection() const {
      return DwarfDebugInlineSection;
    }
    const MCSection *getDwarfStrSection() const { return DwarfStrSection; }
    const MCSection *getDwarfLocSection() const { return DwarfLocSection; }
    const MCSection *getDwarfARangesSection() const { return DwarfARangesSection;}
    const MCSection *getDwarfRangesSection() const { return DwarfRangesSection; }
    const MCSection *getDwarfMacroInfoSection() const {
      return DwarfMacroInfoSection;
    }
    const MCSection *getTLSExtraDataSection() const {
      return TLSExtraDataSection;
    }
    const MCSection *getTLSDataSection() const { return TLSDataSection; }
    const MCSection *getTLSBSSSection() const { return TLSBSSSection; }
  
    /// ELF specific sections.
    ///
    const MCSection *getDataRelSection() const { return DataRelSection; }
    const MCSection *getDataRelLocalSection() const {
      return DataRelLocalSection;
    }
    const MCSection *getDataRelROSection() const { return DataRelROSection; }
    const MCSection *getDataRelROLocalSection() const {
      return DataRelROLocalSection;
    }
    const MCSection *getMergeableConst4Section() const {
      return MergeableConst4Section;
    }
    const MCSection *getMergeableConst8Section() const {
      return MergeableConst8Section;
    }
    const MCSection *getMergeableConst16Section() const {
      return MergeableConst16Section;
    }
  
    /// MachO specific sections.
    ///
    const MCSection *getTLSTLVSection() const { return TLSTLVSection; }
    const MCSection *getTLSThreadInitSection() const {
      return TLSThreadInitSection;
    }
    const MCSection *getCStringSection() const { return CStringSection; }
    const MCSection *getUStringSection() const { return UStringSection; }
    const MCSection *getTextCoalSection() const { return TextCoalSection; }
    const MCSection *getConstTextCoalSection() const {
      return ConstTextCoalSection;
    }
    const MCSection *getConstDataSection() const { return ConstDataSection; }
    const MCSection *getDataCoalSection() const { return DataCoalSection; }
    const MCSection *getDataCommonSection() const { return DataCommonSection; }
    const MCSection *getDataBSSSection() const { return DataBSSSection; }
    const MCSection *getFourByteConstantSection() const {
      return FourByteConstantSection;
    }
    const MCSection *getEightByteConstantSection() const {
      return EightByteConstantSection;
    }
    const MCSection *getSixteenByteConstantSection() const {
      return SixteenByteConstantSection;
    }
    const MCSection *getLazySymbolPointerSection() const {
      return LazySymbolPointerSection;
    }
    const MCSection *getNonLazySymbolPointerSection() const {
      return NonLazySymbolPointerSection;
    }
  
    /// COFF specific sections.
    ///
    const MCSection *getDrectveSection() const { return DrectveSection; }
    const MCSection *getPDataSection() const { return PDataSection; }
    const MCSection *getXDataSection() const { return XDataSection; }
  
    const MCSection *getEHFrameSection() {
      if (!EHFrameSection)
        InitEHFrameSection();
      return EHFrameSection;
    }
  
  private:
    enum Environment { IsMachO, IsELF, IsCOFF };
    Environment Env;
    Reloc::Model RelocM;
    CodeModel::Model CMModel;
    MCContext *Ctx;
  
    void InitMachOMCObjectFileInfo(Triple T);
    void InitELFMCObjectFileInfo(Triple T);
    void InitCOFFMCObjectFileInfo(Triple T);
  
    /// InitEHFrameSection - Initialize EHFrameSection on demand.
    ///
    void InitEHFrameSection();
  };
  
  } // end namespace llvm
  
  #endif
  