Home | History | Annotate | Download | only in MC 
      1 //===-- llvm/MC/MCObjectFileInfo.h - Object File Info -----------*- C++ -*-===//
      2 //
      3 //                     The LLVM Compiler Infrastructure
      4 //
      5 // This file is distributed under the University of Illinois Open Source
      6 // License. See LICENSE.TXT for details.
      7 //
      8 //===----------------------------------------------------------------------===//
      9 //
     10 // This file describes common object file formats.
     11 //
     12 //===----------------------------------------------------------------------===//
     13 
     14 #ifndef LLVM_MC_MCBJECTFILEINFO_H
     15 #define LLVM_MC_MCBJECTFILEINFO_H
     16 
     17 #include "llvm/ADT/Triple.h"
     18 #include "llvm/Support/CodeGen.h"
     19 
     20 namespace llvm {
     21   class MCContext;
     22   class MCSection;
     23   class StringRef;
     24 
     25 class MCObjectFileInfo {
     26 protected:
     27   /// CommDirectiveSupportsAlignment - True if .comm supports alignment.  This
     28   /// is a hack for as long as we support 10.4 Tiger, whose assembler doesn't
     29   /// support alignment on comm.
     30   bool CommDirectiveSupportsAlignment;
     31 
     32   /// SupportsWeakEmptyEHFrame - True if target object file supports a
     33   /// weak_definition of constant 0 for an omitted EH frame.
     34   bool SupportsWeakOmittedEHFrame;
     35 
     36   /// SupportsCompactUnwindWithoutEHFrame - True if the target object file
     37   /// supports emitting a compact unwind section without an associated EH frame
     38   /// section.
     39   bool SupportsCompactUnwindWithoutEHFrame;
     40 
     41   /// PersonalityEncoding, LSDAEncoding, TTypeEncoding - Some encoding values
     42   /// for EH.
     43   unsigned PersonalityEncoding;
     44   unsigned LSDAEncoding;
     45   unsigned FDECFIEncoding;
     46   unsigned TTypeEncoding;
     47 
     48   /// Section flags for eh_frame
     49   unsigned EHSectionType;
     50   unsigned EHSectionFlags;
     51 
     52   /// CompactUnwindDwarfEHFrameOnly - Compact unwind encoding indicating that we
     53   /// should emit only an EH frame.
     54   unsigned CompactUnwindDwarfEHFrameOnly;
     55 
     56   /// TextSection - Section directive for standard text.
     57   ///
     58   const MCSection *TextSection;
     59 
     60   /// DataSection - Section directive for standard data.
     61   ///
     62   const MCSection *DataSection;
     63 
     64   /// BSSSection - Section that is default initialized to zero.
     65   const MCSection *BSSSection;
     66 
     67   /// ReadOnlySection - Section that is readonly and can contain arbitrary
     68   /// initialized data.  Targets are not required to have a readonly section.
     69   /// If they don't, various bits of code will fall back to using the data
     70   /// section for constants.
     71   const MCSection *ReadOnlySection;
     72 
     73   /// StaticCtorSection - This section contains the static constructor pointer
     74   /// list.
     75   const MCSection *StaticCtorSection;
     76 
     77   /// StaticDtorSection - This section contains the static destructor pointer
     78   /// list.
     79   const MCSection *StaticDtorSection;
     80 
     81   /// LSDASection - If exception handling is supported by the target, this is
     82   /// the section the Language Specific Data Area information is emitted to.
     83   const MCSection *LSDASection;
     84 
     85   /// CompactUnwindSection - If exception handling is supported by the target
     86   /// and the target can support a compact representation of the CIE and FDE,
     87   /// this is the section to emit them into.
     88   const MCSection *CompactUnwindSection;
     89 
     90   // Dwarf sections for debug info.  If a target supports debug info, these must
     91   // be set.
     92   const MCSection *DwarfAbbrevSection;
     93   const MCSection *DwarfInfoSection;
     94   const MCSection *DwarfLineSection;
     95   const MCSection *DwarfFrameSection;
     96   const MCSection *DwarfPubTypesSection;
     97   const MCSection *DwarfDebugInlineSection;
     98   const MCSection *DwarfStrSection;
     99   const MCSection *DwarfLocSection;
    100   const MCSection *DwarfARangesSection;
    101   const MCSection *DwarfRangesSection;
    102   const MCSection *DwarfMacroInfoSection;
    103   // The pubnames section is no longer generated by default.  The generation
    104   // can be enabled by a compiler flag.
    105   const MCSection *DwarfPubNamesSection;
    106 
    107   // DWARF5 Experimental Debug Info Sections
    108   /// DwarfAccelNamesSection, DwarfAccelObjCSection,
    109   /// DwarfAccelNamespaceSection, DwarfAccelTypesSection -
    110   /// If we use the DWARF accelerated hash tables then we want to emit these
    111   /// sections.
    112   const MCSection *DwarfAccelNamesSection;
    113   const MCSection *DwarfAccelObjCSection;
    114   const MCSection *DwarfAccelNamespaceSection;
    115   const MCSection *DwarfAccelTypesSection;
    116 
    117   /// These are used for the Fission separate debug information files.
    118   const MCSection *DwarfInfoDWOSection;
    119   const MCSection *DwarfAbbrevDWOSection;
    120   const MCSection *DwarfStrDWOSection;
    121   const MCSection *DwarfLineDWOSection;
    122   const MCSection *DwarfLocDWOSection;
    123   const MCSection *DwarfStrOffDWOSection;
    124   const MCSection *DwarfAddrSection;
    125 
    126   /// Sections for newer gnu pubnames and pubtypes.
    127   const MCSection *DwarfGnuPubNamesSection;
    128   const MCSection *DwarfGnuPubTypesSection;
    129 
    130   const MCSection *COFFDebugSymbolsSection;
    131 
    132   // Extra TLS Variable Data section.  If the target needs to put additional
    133   // information for a TLS variable, it'll go here.
    134   const MCSection *TLSExtraDataSection;
    135 
    136   /// TLSDataSection - Section directive for Thread Local data.
    137   /// ELF, MachO and COFF.
    138   const MCSection *TLSDataSection;        // Defaults to ".tdata".
    139 
    140   /// TLSBSSSection - Section directive for Thread Local uninitialized data.
    141   /// Null if this target doesn't support a BSS section.
    142   /// ELF and MachO only.
    143   const MCSection *TLSBSSSection;         // Defaults to ".tbss".
    144 
    145   /// StackMap section.
    146   const MCSection *StackMapSection;
    147 
    148   /// EHFrameSection - EH frame section. It is initialized on demand so it
    149   /// can be overwritten (with uniquing).
    150   const MCSection *EHFrameSection;
    151 
    152   /// ELF specific sections.
    153   ///
    154   const MCSection *DataRelSection;
    155   const MCSection *DataRelLocalSection;
    156   const MCSection *DataRelROSection;
    157   const MCSection *DataRelROLocalSection;
    158   const MCSection *MergeableConst4Section;
    159   const MCSection *MergeableConst8Section;
    160   const MCSection *MergeableConst16Section;
    161 
    162   /// MachO specific sections.
    163   ///
    164 
    165   /// TLSTLVSection - Section for thread local structure information.
    166   /// Contains the source code name of the variable, visibility and a pointer
    167   /// to the initial value (.tdata or .tbss).
    168   const MCSection *TLSTLVSection;         // Defaults to ".tlv".
    169 
    170   /// TLSThreadInitSection - Section for thread local data initialization
    171   /// functions.
    172   const MCSection *TLSThreadInitSection;  // Defaults to ".thread_init_func".
    173 
    174   const MCSection *CStringSection;
    175   const MCSection *UStringSection;
    176   const MCSection *TextCoalSection;
    177   const MCSection *ConstTextCoalSection;
    178   const MCSection *ConstDataSection;
    179   const MCSection *DataCoalSection;
    180   const MCSection *DataCommonSection;
    181   const MCSection *DataBSSSection;
    182   const MCSection *FourByteConstantSection;
    183   const MCSection *EightByteConstantSection;
    184   const MCSection *SixteenByteConstantSection;
    185   const MCSection *LazySymbolPointerSection;
    186   const MCSection *NonLazySymbolPointerSection;
    187 
    188   /// COFF specific sections.
    189   ///
    190   const MCSection *DrectveSection;
    191   const MCSection *PDataSection;
    192   const MCSection *XDataSection;
    193 
    194 public:
    195   void InitMCObjectFileInfo(StringRef TT, Reloc::Model RM, CodeModel::Model CM,
    196                             MCContext &ctx);
    197 
    198   bool getSupportsWeakOmittedEHFrame() const {
    199     return SupportsWeakOmittedEHFrame;
    200   }
    201   bool getSupportsCompactUnwindWithoutEHFrame() const {
    202     return SupportsCompactUnwindWithoutEHFrame;
    203   }
    204   bool getCommDirectiveSupportsAlignment() const {
    205     return CommDirectiveSupportsAlignment;
    206   }
    207 
    208   unsigned getPersonalityEncoding() const { return PersonalityEncoding; }
    209   unsigned getLSDAEncoding() const { return LSDAEncoding; }
    210   unsigned getFDEEncoding() const { return FDECFIEncoding; }
    211   unsigned getTTypeEncoding() const { return TTypeEncoding; }
    212 
    213   unsigned getCompactUnwindDwarfEHFrameOnly() const {
    214     return CompactUnwindDwarfEHFrameOnly;
    215   }
    216 
    217   const MCSection *getTextSection() const { return TextSection; }
    218   const MCSection *getDataSection() const { return DataSection; }
    219   const MCSection *getBSSSection() const { return BSSSection; }
    220   const MCSection *getLSDASection() const { return LSDASection; }
    221   const MCSection *getCompactUnwindSection() const{
    222     return CompactUnwindSection;
    223   }
    224   const MCSection *getDwarfAbbrevSection() const { return DwarfAbbrevSection; }
    225   const MCSection *getDwarfInfoSection() const { return DwarfInfoSection; }
    226   const MCSection *getDwarfLineSection() const { return DwarfLineSection; }
    227   const MCSection *getDwarfFrameSection() const { return DwarfFrameSection; }
    228   const MCSection *getDwarfPubNamesSection() const{return DwarfPubNamesSection;}
    229   const MCSection *getDwarfPubTypesSection() const{return DwarfPubTypesSection;}
    230   const MCSection *getDwarfGnuPubNamesSection() const {
    231     return DwarfGnuPubNamesSection;
    232   }
    233   const MCSection *getDwarfGnuPubTypesSection() const {
    234     return DwarfGnuPubTypesSection;
    235   }
    236   const MCSection *getDwarfDebugInlineSection() const {
    237     return DwarfDebugInlineSection;
    238   }
    239   const MCSection *getDwarfStrSection() const { return DwarfStrSection; }
    240   const MCSection *getDwarfLocSection() const { return DwarfLocSection; }
    241   const MCSection *getDwarfARangesSection() const { return DwarfARangesSection;}
    242   const MCSection *getDwarfRangesSection() const { return DwarfRangesSection; }
    243   const MCSection *getDwarfMacroInfoSection() const {
    244     return DwarfMacroInfoSection;
    245   }
    246 
    247   // DWARF5 Experimental Debug Info Sections
    248   const MCSection *getDwarfAccelNamesSection() const {
    249     return DwarfAccelNamesSection;
    250   }
    251   const MCSection *getDwarfAccelObjCSection() const {
    252     return DwarfAccelObjCSection;
    253   }
    254   const MCSection *getDwarfAccelNamespaceSection() const {
    255     return DwarfAccelNamespaceSection;
    256   }
    257   const MCSection *getDwarfAccelTypesSection() const {
    258     return DwarfAccelTypesSection;
    259   }
    260   const MCSection *getDwarfInfoDWOSection() const {
    261     return DwarfInfoDWOSection;
    262   }
    263   const MCSection *getDwarfTypesSection(uint64_t Hash) const;
    264   const MCSection *getDwarfTypesDWOSection(uint64_t Hash) const;
    265   const MCSection *getDwarfAbbrevDWOSection() const {
    266     return DwarfAbbrevDWOSection;
    267   }
    268   const MCSection *getDwarfStrDWOSection() const {
    269     return DwarfStrDWOSection;
    270   }
    271   const MCSection *getDwarfLineDWOSection() const {
    272     return DwarfLineDWOSection;
    273   }
    274   const MCSection *getDwarfLocDWOSection() const {
    275     return DwarfLocDWOSection;
    276   }
    277   const MCSection *getDwarfStrOffDWOSection() const {
    278     return DwarfStrOffDWOSection;
    279   }
    280   const MCSection *getDwarfAddrSection() const {
    281     return DwarfAddrSection;
    282   }
    283 
    284   const MCSection *getCOFFDebugSymbolsSection() const {
    285     return COFFDebugSymbolsSection;
    286   }
    287 
    288   const MCSection *getTLSExtraDataSection() const {
    289     return TLSExtraDataSection;
    290   }
    291   const MCSection *getTLSDataSection() const { return TLSDataSection; }
    292   const MCSection *getTLSBSSSection() const { return TLSBSSSection; }
    293 
    294   const MCSection *getStackMapSection() const { return StackMapSection; }
    295 
    296   /// ELF specific sections.
    297   ///
    298   const MCSection *getDataRelSection() const { return DataRelSection; }
    299   const MCSection *getDataRelLocalSection() const {
    300     return DataRelLocalSection;
    301   }
    302   const MCSection *getDataRelROSection() const { return DataRelROSection; }
    303   const MCSection *getDataRelROLocalSection() const {
    304     return DataRelROLocalSection;
    305   }
    306   const MCSection *getMergeableConst4Section() const {
    307     return MergeableConst4Section;
    308   }
    309   const MCSection *getMergeableConst8Section() const {
    310     return MergeableConst8Section;
    311   }
    312   const MCSection *getMergeableConst16Section() const {
    313     return MergeableConst16Section;
    314   }
    315 
    316   /// MachO specific sections.
    317   ///
    318   const MCSection *getTLSTLVSection() const { return TLSTLVSection; }
    319   const MCSection *getTLSThreadInitSection() const {
    320     return TLSThreadInitSection;
    321   }
    322   const MCSection *getCStringSection() const { return CStringSection; }
    323   const MCSection *getUStringSection() const { return UStringSection; }
    324   const MCSection *getTextCoalSection() const { return TextCoalSection; }
    325   const MCSection *getConstTextCoalSection() const {
    326     return ConstTextCoalSection;
    327   }
    328   const MCSection *getConstDataSection() const { return ConstDataSection; }
    329   const MCSection *getDataCoalSection() const { return DataCoalSection; }
    330   const MCSection *getDataCommonSection() const { return DataCommonSection; }
    331   const MCSection *getDataBSSSection() const { return DataBSSSection; }
    332   const MCSection *getFourByteConstantSection() const {
    333     return FourByteConstantSection;
    334   }
    335   const MCSection *getEightByteConstantSection() const {
    336     return EightByteConstantSection;
    337   }
    338   const MCSection *getSixteenByteConstantSection() const {
    339     return SixteenByteConstantSection;
    340   }
    341   const MCSection *getLazySymbolPointerSection() const {
    342     return LazySymbolPointerSection;
    343   }
    344   const MCSection *getNonLazySymbolPointerSection() const {
    345     return NonLazySymbolPointerSection;
    346   }
    347 
    348   /// COFF specific sections.
    349   ///
    350   const MCSection *getDrectveSection() const { return DrectveSection; }
    351   const MCSection *getPDataSection() const { return PDataSection; }
    352   const MCSection *getXDataSection() const { return XDataSection; }
    353 
    354   const MCSection *getEHFrameSection() {
    355     if (!EHFrameSection)
    356       InitEHFrameSection();
    357     return EHFrameSection;
    358   }
    359 
    360   enum Environment { IsMachO, IsELF, IsCOFF };
    361   Environment getObjectFileType() const {
    362     return Env;
    363   }
    364 
    365   Reloc::Model getRelocM() const {
    366     return RelocM;
    367   }
    368 
    369 private:
    370   Environment Env;
    371   Reloc::Model RelocM;
    372   CodeModel::Model CMModel;
    373   MCContext *Ctx;
    374   Triple TT;
    375 
    376   void InitMachOMCObjectFileInfo(Triple T);
    377   void InitELFMCObjectFileInfo(Triple T);
    378   void InitCOFFMCObjectFileInfo(Triple T);
    379 
    380   /// InitEHFrameSection - Initialize EHFrameSection on demand.
    381   ///
    382   void InitEHFrameSection();
    383 
    384 public:
    385   const Triple &getTargetTriple() const { return TT; }
    386 };
    387 
    388 } // end namespace llvm
    389 
    390 #endif
    391