include/llvm/MC/MCObjectFileInfo.h

   1 //===-- llvm/MC/MCObjectFileInfo.h - Object File Info -----------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file describes common object file formats.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #ifndef LLVM_MC_MCOBJECTFILEINFO_H
  14 #define LLVM_MC_MCOBJECTFILEINFO_H
  15
  16 #include "llvm/ADT/DenseMap.h"
  17 #include "llvm/ADT/Triple.h"
  18 #include "llvm/MC/MCSymbol.h"
  19 #include "llvm/Support/CodeGen.h"
  20 #include "llvm/Support/VersionTuple.h"
  21
  22 namespace llvm {
  23 class MCContext;
  24 class MCSection;
  25
  26 class MCObjectFileInfo {
  27 protected:
  28   /// True if .comm supports alignment.  This is a hack for as long as we
  29   /// support 10.4 Tiger, whose assembler doesn't support alignment on comm.
  30   bool CommDirectiveSupportsAlignment;
  31
  32   /// True if target object file supports a weak_definition of constant 0 for an
  33   /// omitted EH frame.
  34   bool SupportsWeakOmittedEHFrame;
  35
  36   /// True if the target object file supports emitting a compact unwind section
  37   /// without an associated EH frame section.
  38   bool SupportsCompactUnwindWithoutEHFrame;
  39
  40   /// OmitDwarfIfHaveCompactUnwind - True if the target object file
  41   /// supports having some functions with compact unwind and other with
  42   /// dwarf unwind.
  43   bool OmitDwarfIfHaveCompactUnwind;
  44
  45   /// FDE CFI encoding. Controls the encoding of the begin label in the
  46   /// .eh_frame section. Unlike the LSDA encoding, personality encoding, and
  47   /// type encodings, this is something that the assembler just "knows" about
  48   /// its target
  49   unsigned FDECFIEncoding = 0;
  50
  51   /// Compact unwind encoding indicating that we should emit only an EH frame.
  52   unsigned CompactUnwindDwarfEHFrameOnly;
  53
  54   /// Section directive for standard text.
  55   MCSection *TextSection;
  56
  57   /// Section directive for standard data.
  58   MCSection *DataSection;
  59
  60   /// Section that is default initialized to zero.
  61   MCSection *BSSSection;
  62
  63   /// Section that is readonly and can contain arbitrary initialized data.
  64   /// Targets are not required to have a readonly section. If they don't,
  65   /// various bits of code will fall back to using the data section for
  66   /// constants.
  67   MCSection *ReadOnlySection;
  68
  69   /// If exception handling is supported by the target, this is the section the
  70   /// Language Specific Data Area information is emitted to.
  71   MCSection *LSDASection;
  72
  73   /// If exception handling is supported by the target and the target can
  74   /// support a compact representation of the CIE and FDE, this is the section
  75   /// to emit them into.
  76   MCSection *CompactUnwindSection;
  77
  78   // Dwarf sections for debug info.  If a target supports debug info, these must
  79   // be set.
  80   MCSection *DwarfAbbrevSection;
  81   MCSection *DwarfInfoSection;
  82   MCSection *DwarfLineSection;
  83   MCSection *DwarfLineStrSection;
  84   MCSection *DwarfFrameSection;
  85   MCSection *DwarfPubTypesSection;
  86   const MCSection *DwarfDebugInlineSection;
  87   MCSection *DwarfStrSection;
  88   MCSection *DwarfLocSection;
  89   MCSection *DwarfARangesSection;
  90   MCSection *DwarfRangesSection;
  91   MCSection *DwarfMacinfoSection;
  92   // The pubnames section is no longer generated by default.  The generation
  93   // can be enabled by a compiler flag.
  94   MCSection *DwarfPubNamesSection;
  95
  96   /// Accelerator table sections. DwarfDebugNamesSection is the DWARF v5
  97   /// accelerator table, while DwarfAccelNamesSection, DwarfAccelObjCSection,
  98   /// DwarfAccelNamespaceSection, DwarfAccelTypesSection are pre-DWARF v5
  99   /// extensions.
 100   MCSection *DwarfDebugNamesSection;
 101   MCSection *DwarfAccelNamesSection;
 102   MCSection *DwarfAccelObjCSection;
 103   MCSection *DwarfAccelNamespaceSection;
 104   MCSection *DwarfAccelTypesSection;
 105
 106   // These are used for the Fission separate debug information files.
 107   MCSection *DwarfInfoDWOSection;
 108   MCSection *DwarfTypesDWOSection;
 109   MCSection *DwarfAbbrevDWOSection;
 110   MCSection *DwarfStrDWOSection;
 111   MCSection *DwarfLineDWOSection;
 112   MCSection *DwarfLocDWOSection;
 113   MCSection *DwarfStrOffDWOSection;
 114
 115   /// The DWARF v5 string offset and address table sections.
 116   MCSection *DwarfStrOffSection;
 117   MCSection *DwarfAddrSection;
 118   /// The DWARF v5 range list section.
 119   MCSection *DwarfRnglistsSection;
 120   /// The DWARF v5 locations list section.
 121   MCSection *DwarfLoclistsSection;
 122
 123   /// The DWARF v5 range list section for fission.
 124   MCSection *DwarfRnglistsDWOSection;
 125
 126   // These are for Fission DWP files.
 127   MCSection *DwarfCUIndexSection;
 128   MCSection *DwarfTUIndexSection;
 129
 130   /// Section for newer gnu pubnames.
 131   MCSection *DwarfGnuPubNamesSection;
 132   /// Section for newer gnu pubtypes.
 133   MCSection *DwarfGnuPubTypesSection;
 134
 135   // Section for Swift AST
 136   MCSection *DwarfSwiftASTSection;
 137
 138   MCSection *COFFDebugSymbolsSection;
 139   MCSection *COFFDebugTypesSection;
 140   MCSection *COFFGlobalTypeHashesSection;
 141
 142   /// Extra TLS Variable Data section.
 143   ///
 144   /// If the target needs to put additional information for a TLS variable,
 145   /// it'll go here.
 146   MCSection *TLSExtraDataSection;
 147
 148   /// Section directive for Thread Local data. ELF, MachO, COFF, and Wasm.
 149   MCSection *TLSDataSection; // Defaults to ".tdata".
 150
 151   /// Section directive for Thread Local uninitialized data.
 152   ///
 153   /// Null if this target doesn't support a BSS section. ELF and MachO only.
 154   MCSection *TLSBSSSection; // Defaults to ".tbss".
 155
 156   /// StackMap section.
 157   MCSection *StackMapSection;
 158
 159   /// FaultMap section.
 160   MCSection *FaultMapSection;
 161
 162   /// EH frame section.
 163   ///
 164   /// It is initialized on demand so it can be overwritten (with uniquing).
 165   MCSection *EHFrameSection;
 166
 167   /// Section containing metadata on function stack sizes.
 168   MCSection *StackSizesSection;
 169   mutable DenseMap<const MCSymbol *, unsigned> StackSizesUniquing;
 170
 171   // ELF specific sections.
 172   MCSection *DataRelROSection;
 173   MCSection *MergeableConst4Section;
 174   MCSection *MergeableConst8Section;
 175   MCSection *MergeableConst16Section;
 176   MCSection *MergeableConst32Section;
 177
 178   // MachO specific sections.
 179
 180   /// Section for thread local structure information.
 181   ///
 182   /// Contains the source code name of the variable, visibility and a pointer to
 183   /// the initial value (.tdata or .tbss).
 184   MCSection *TLSTLVSection; // Defaults to ".tlv".
 185
 186   /// Section for thread local data initialization functions.
 187   const MCSection *TLSThreadInitSection; // Defaults to ".thread_init_func".
 188
 189   MCSection *CStringSection;
 190   MCSection *UStringSection;
 191   MCSection *TextCoalSection;
 192   MCSection *ConstTextCoalSection;
 193   MCSection *ConstDataSection;
 194   MCSection *DataCoalSection;
 195   MCSection *ConstDataCoalSection;
 196   MCSection *DataCommonSection;
 197   MCSection *DataBSSSection;
 198   MCSection *FourByteConstantSection;
 199   MCSection *EightByteConstantSection;
 200   MCSection *SixteenByteConstantSection;
 201   MCSection *LazySymbolPointerSection;
 202   MCSection *NonLazySymbolPointerSection;
 203   MCSection *ThreadLocalPointerSection;
 204
 205   /// COFF specific sections.
 206   MCSection *DrectveSection;
 207   MCSection *PDataSection;
 208   MCSection *XDataSection;
 209   MCSection *SXDataSection;
 210   MCSection *GFIDsSection;
 211
 212 public:
 213   void InitMCObjectFileInfo(const Triple &TT, bool PIC, MCContext &ctx,
 214                             bool LargeCodeModel = false);
 215
 216   bool getSupportsWeakOmittedEHFrame() const {
 217     return SupportsWeakOmittedEHFrame;
 218   }
 219   bool getSupportsCompactUnwindWithoutEHFrame() const {
 220     return SupportsCompactUnwindWithoutEHFrame;
 221   }
 222   bool getOmitDwarfIfHaveCompactUnwind() const {
 223     return OmitDwarfIfHaveCompactUnwind;
 224   }
 225
 226   bool getCommDirectiveSupportsAlignment() const {
 227     return CommDirectiveSupportsAlignment;
 228   }
 229
 230   unsigned getFDEEncoding() const { return FDECFIEncoding; }
 231
 232   unsigned getCompactUnwindDwarfEHFrameOnly() const {
 233     return CompactUnwindDwarfEHFrameOnly;
 234   }
 235
 236   MCSection *getTextSection() const { return TextSection; }
 237   MCSection *getDataSection() const { return DataSection; }
 238   MCSection *getBSSSection() const { return BSSSection; }
 239   MCSection *getReadOnlySection() const { return ReadOnlySection; }
 240   MCSection *getLSDASection() const { return LSDASection; }
 241   MCSection *getCompactUnwindSection() const { return CompactUnwindSection; }
 242   MCSection *getDwarfAbbrevSection() const { return DwarfAbbrevSection; }
 243   MCSection *getDwarfInfoSection() const { return DwarfInfoSection; }
 244   MCSection *getDwarfInfoSection(uint64_t Hash) const {
 245     return getDwarfComdatSection(".debug_info", Hash);
 246   }
 247   MCSection *getDwarfLineSection() const { return DwarfLineSection; }
 248   MCSection *getDwarfLineStrSection() const { return DwarfLineStrSection; }
 249   MCSection *getDwarfFrameSection() const { return DwarfFrameSection; }
 250   MCSection *getDwarfPubNamesSection() const { return DwarfPubNamesSection; }
 251   MCSection *getDwarfPubTypesSection() const { return DwarfPubTypesSection; }
 252   MCSection *getDwarfGnuPubNamesSection() const {
 253     return DwarfGnuPubNamesSection;
 254   }
 255   MCSection *getDwarfGnuPubTypesSection() const {
 256     return DwarfGnuPubTypesSection;
 257   }
 258   const MCSection *getDwarfDebugInlineSection() const {
 259     return DwarfDebugInlineSection;
 260   }
 261   MCSection *getDwarfStrSection() const { return DwarfStrSection; }
 262   MCSection *getDwarfLocSection() const { return DwarfLocSection; }
 263   MCSection *getDwarfARangesSection() const { return DwarfARangesSection; }
 264   MCSection *getDwarfRangesSection() const { return DwarfRangesSection; }
 265   MCSection *getDwarfRnglistsSection() const { return DwarfRnglistsSection; }
 266   MCSection *getDwarfLoclistsSection() const { return DwarfLoclistsSection; }
 267   MCSection *getDwarfMacinfoSection() const { return DwarfMacinfoSection; }
 268
 269   MCSection *getDwarfDebugNamesSection() const {
 270     return DwarfDebugNamesSection;
 271   }
 272   MCSection *getDwarfAccelNamesSection() const {
 273     return DwarfAccelNamesSection;
 274   }
 275   MCSection *getDwarfAccelObjCSection() const { return DwarfAccelObjCSection; }
 276   MCSection *getDwarfAccelNamespaceSection() const {
 277     return DwarfAccelNamespaceSection;
 278   }
 279   MCSection *getDwarfAccelTypesSection() const {
 280     return DwarfAccelTypesSection;
 281   }
 282   MCSection *getDwarfInfoDWOSection() const { return DwarfInfoDWOSection; }
 283   MCSection *getDwarfTypesSection(uint64_t Hash) const {
 284     return getDwarfComdatSection(".debug_types", Hash);
 285   }
 286   MCSection *getDwarfTypesDWOSection() const { return DwarfTypesDWOSection; }
 287   MCSection *getDwarfAbbrevDWOSection() const { return DwarfAbbrevDWOSection; }
 288   MCSection *getDwarfStrDWOSection() const { return DwarfStrDWOSection; }
 289   MCSection *getDwarfLineDWOSection() const { return DwarfLineDWOSection; }
 290   MCSection *getDwarfLocDWOSection() const { return DwarfLocDWOSection; }
 291   MCSection *getDwarfStrOffDWOSection() const { return DwarfStrOffDWOSection; }
 292   MCSection *getDwarfStrOffSection() const { return DwarfStrOffSection; }
 293   MCSection *getDwarfAddrSection() const { return DwarfAddrSection; }
 294   MCSection *getDwarfRnglistsDWOSection() const {
 295     return DwarfRnglistsDWOSection;
 296   }
 297   MCSection *getDwarfCUIndexSection() const { return DwarfCUIndexSection; }
 298   MCSection *getDwarfTUIndexSection() const { return DwarfTUIndexSection; }
 299   MCSection *getDwarfSwiftASTSection() const { return DwarfSwiftASTSection; }
 300
 301   MCSection *getCOFFDebugSymbolsSection() const {
 302     return COFFDebugSymbolsSection;
 303   }
 304   MCSection *getCOFFDebugTypesSection() const {
 305     return COFFDebugTypesSection;
 306   }
 307   MCSection *getCOFFGlobalTypeHashesSection() const {
 308     return COFFGlobalTypeHashesSection;
 309   }
 310
 311   MCSection *getTLSExtraDataSection() const { return TLSExtraDataSection; }
 312   const MCSection *getTLSDataSection() const { return TLSDataSection; }
 313   MCSection *getTLSBSSSection() const { return TLSBSSSection; }
 314
 315   MCSection *getStackMapSection() const { return StackMapSection; }
 316   MCSection *getFaultMapSection() const { return FaultMapSection; }
 317
 318   MCSection *getStackSizesSection(const MCSection &TextSec) const;
 319
 320   // ELF specific sections.
 321   MCSection *getDataRelROSection() const { return DataRelROSection; }
 322   const MCSection *getMergeableConst4Section() const {
 323     return MergeableConst4Section;
 324   }
 325   const MCSection *getMergeableConst8Section() const {
 326     return MergeableConst8Section;
 327   }
 328   const MCSection *getMergeableConst16Section() const {
 329     return MergeableConst16Section;
 330   }
 331   const MCSection *getMergeableConst32Section() const {
 332     return MergeableConst32Section;
 333   }
 334
 335   // MachO specific sections.
 336   const MCSection *getTLSTLVSection() const { return TLSTLVSection; }
 337   const MCSection *getTLSThreadInitSection() const {
 338     return TLSThreadInitSection;
 339   }
 340   const MCSection *getCStringSection() const { return CStringSection; }
 341   const MCSection *getUStringSection() const { return UStringSection; }
 342   MCSection *getTextCoalSection() const { return TextCoalSection; }
 343   const MCSection *getConstTextCoalSection() const {
 344     return ConstTextCoalSection;
 345   }
 346   const MCSection *getConstDataSection() const { return ConstDataSection; }
 347   const MCSection *getDataCoalSection() const { return DataCoalSection; }
 348   const MCSection *getConstDataCoalSection() const {
 349     return ConstDataCoalSection;
 350   }
 351   const MCSection *getDataCommonSection() const { return DataCommonSection; }
 352   MCSection *getDataBSSSection() const { return DataBSSSection; }
 353   const MCSection *getFourByteConstantSection() const {
 354     return FourByteConstantSection;
 355   }
 356   const MCSection *getEightByteConstantSection() const {
 357     return EightByteConstantSection;
 358   }
 359   const MCSection *getSixteenByteConstantSection() const {
 360     return SixteenByteConstantSection;
 361   }
 362   MCSection *getLazySymbolPointerSection() const {
 363     return LazySymbolPointerSection;
 364   }
 365   MCSection *getNonLazySymbolPointerSection() const {
 366     return NonLazySymbolPointerSection;
 367   }
 368   MCSection *getThreadLocalPointerSection() const {
 369     return ThreadLocalPointerSection;
 370   }
 371
 372   // COFF specific sections.
 373   MCSection *getDrectveSection() const { return DrectveSection; }
 374   MCSection *getPDataSection() const { return PDataSection; }
 375   MCSection *getXDataSection() const { return XDataSection; }
 376   MCSection *getSXDataSection() const { return SXDataSection; }
 377   MCSection *getGFIDsSection() const { return GFIDsSection; }
 378
 379   MCSection *getEHFrameSection() {
 380     return EHFrameSection;
 381   }
 382
 383   enum Environment { IsMachO, IsELF, IsCOFF, IsWasm };
 384   Environment getObjectFileType() const { return Env; }
 385
 386   bool isPositionIndependent() const { return PositionIndependent; }
 387
 388 private:
 389   Environment Env;
 390   bool PositionIndependent;
 391   MCContext *Ctx;
 392   Triple TT;
 393   VersionTuple SDKVersion;
 394
 395   void initMachOMCObjectFileInfo(const Triple &T);
 396   void initELFMCObjectFileInfo(const Triple &T, bool Large);
 397   void initCOFFMCObjectFileInfo(const Triple &T);
 398   void initWasmMCObjectFileInfo(const Triple &T);
 399   MCSection *getDwarfComdatSection(const char *Name, uint64_t Hash) const;
 400
 401 public:
 402   const Triple &getTargetTriple() const { return TT; }
 403
 404   void setSDKVersion(const VersionTuple &TheSDKVersion) {
 405     SDKVersion = TheSDKVersion;
 406   }
 407
 408   const VersionTuple &getSDKVersion() const { return SDKVersion; }
 409 };
 410
 411 } // end namespace llvm
 412
 413 #endif