1 //===-- MCObjectFileInfo.cpp - Object File Information --------------------===//
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 #include "llvm/MC/MCObjectFileInfo.h"
11 #include "llvm/ADT/StringExtras.h"
12 #include "llvm/ADT/Triple.h"
13 #include "llvm/BinaryFormat/COFF.h"
14 #include "llvm/BinaryFormat/ELF.h"
15 #include "llvm/MC/MCAsmInfo.h"
16 #include "llvm/MC/MCContext.h"
17 #include "llvm/MC/MCSection.h"
18 #include "llvm/MC/MCSectionCOFF.h"
19 #include "llvm/MC/MCSectionELF.h"
20 #include "llvm/MC/MCSectionMachO.h"
21 #include "llvm/MC/MCSectionWasm.h"
22 
23 using namespace llvm;
24 
25 static bool useCompactUnwind(const Triple &T) {
26   // Only on darwin.
27   if (!T.isOSDarwin())
28     return false;
29 
30   // aarch64 always has it.
31   if (T.getArch() == Triple::aarch64)
32     return true;
33 
34   // armv7k always has it.
35   if (T.isWatchABI())
36     return true;
37 
38   // Use it on newer version of OS X.
39   if (T.isMacOSX() && !T.isMacOSXVersionLT(10, 6))
40     return true;
41 
42   // And the iOS simulator.
43   if (T.isiOS() &&
44       (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86))
45     return true;
46 
47   return false;
48 }
49 
50 void MCObjectFileInfo::initMachOMCObjectFileInfo(const Triple &T) {
51   // MachO
52   SupportsWeakOmittedEHFrame = false;
53 
54   EHFrameSection = Ctx->getMachOSection(
55       "__TEXT", "__eh_frame",
56       MachO::S_COALESCED | MachO::S_ATTR_NO_TOC |
57           MachO::S_ATTR_STRIP_STATIC_SYMS | MachO::S_ATTR_LIVE_SUPPORT,
58       SectionKind::getReadOnly());
59 
60   if (T.isOSDarwin() && T.getArch() == Triple::aarch64)
61     SupportsCompactUnwindWithoutEHFrame = true;
62 
63   if (T.isWatchABI())
64     OmitDwarfIfHaveCompactUnwind = true;
65 
66   PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel
67     | dwarf::DW_EH_PE_sdata4;
68   LSDAEncoding = FDECFIEncoding = dwarf::DW_EH_PE_pcrel;
69   TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
70     dwarf::DW_EH_PE_sdata4;
71 
72   // .comm doesn't support alignment before Leopard.
73   if (T.isMacOSX() && T.isMacOSXVersionLT(10, 5))
74     CommDirectiveSupportsAlignment = false;
75 
76   TextSection // .text
77     = Ctx->getMachOSection("__TEXT", "__text",
78                            MachO::S_ATTR_PURE_INSTRUCTIONS,
79                            SectionKind::getText());
80   DataSection // .data
81       = Ctx->getMachOSection("__DATA", "__data", 0, SectionKind::getData());
82 
83   // BSSSection might not be expected initialized on msvc.
84   BSSSection = nullptr;
85 
86   TLSDataSection // .tdata
87       = Ctx->getMachOSection("__DATA", "__thread_data",
88                              MachO::S_THREAD_LOCAL_REGULAR,
89                              SectionKind::getData());
90   TLSBSSSection // .tbss
91     = Ctx->getMachOSection("__DATA", "__thread_bss",
92                            MachO::S_THREAD_LOCAL_ZEROFILL,
93                            SectionKind::getThreadBSS());
94 
95   // TODO: Verify datarel below.
96   TLSTLVSection // .tlv
97       = Ctx->getMachOSection("__DATA", "__thread_vars",
98                              MachO::S_THREAD_LOCAL_VARIABLES,
99                              SectionKind::getData());
100 
101   TLSThreadInitSection = Ctx->getMachOSection(
102       "__DATA", "__thread_init", MachO::S_THREAD_LOCAL_INIT_FUNCTION_POINTERS,
103       SectionKind::getData());
104 
105   CStringSection // .cstring
106     = Ctx->getMachOSection("__TEXT", "__cstring",
107                            MachO::S_CSTRING_LITERALS,
108                            SectionKind::getMergeable1ByteCString());
109   UStringSection
110     = Ctx->getMachOSection("__TEXT","__ustring", 0,
111                            SectionKind::getMergeable2ByteCString());
112   FourByteConstantSection // .literal4
113     = Ctx->getMachOSection("__TEXT", "__literal4",
114                            MachO::S_4BYTE_LITERALS,
115                            SectionKind::getMergeableConst4());
116   EightByteConstantSection // .literal8
117     = Ctx->getMachOSection("__TEXT", "__literal8",
118                            MachO::S_8BYTE_LITERALS,
119                            SectionKind::getMergeableConst8());
120 
121   SixteenByteConstantSection // .literal16
122       = Ctx->getMachOSection("__TEXT", "__literal16",
123                              MachO::S_16BYTE_LITERALS,
124                              SectionKind::getMergeableConst16());
125 
126   ReadOnlySection  // .const
127     = Ctx->getMachOSection("__TEXT", "__const", 0,
128                            SectionKind::getReadOnly());
129 
130   // If the target is not powerpc, map the coal sections to the non-coal
131   // sections.
132   //
133   // "__TEXT/__textcoal_nt" => section "__TEXT/__text"
134   // "__TEXT/__const_coal"  => section "__TEXT/__const"
135   // "__DATA/__datacoal_nt" => section "__DATA/__data"
136   Triple::ArchType ArchTy = T.getArch();
137 
138   if (ArchTy == Triple::ppc || ArchTy == Triple::ppc64) {
139     TextCoalSection
140       = Ctx->getMachOSection("__TEXT", "__textcoal_nt",
141                              MachO::S_COALESCED |
142                              MachO::S_ATTR_PURE_INSTRUCTIONS,
143                              SectionKind::getText());
144     ConstTextCoalSection
145       = Ctx->getMachOSection("__TEXT", "__const_coal",
146                              MachO::S_COALESCED,
147                              SectionKind::getReadOnly());
148     DataCoalSection = Ctx->getMachOSection(
149         "__DATA", "__datacoal_nt", MachO::S_COALESCED, SectionKind::getData());
150   } else {
151     TextCoalSection = TextSection;
152     ConstTextCoalSection = ReadOnlySection;
153     DataCoalSection = DataSection;
154   }
155 
156   ConstDataSection  // .const_data
157     = Ctx->getMachOSection("__DATA", "__const", 0,
158                            SectionKind::getReadOnlyWithRel());
159   DataCommonSection
160     = Ctx->getMachOSection("__DATA","__common",
161                            MachO::S_ZEROFILL,
162                            SectionKind::getBSS());
163   DataBSSSection
164     = Ctx->getMachOSection("__DATA","__bss", MachO::S_ZEROFILL,
165                            SectionKind::getBSS());
166 
167 
168   LazySymbolPointerSection
169     = Ctx->getMachOSection("__DATA", "__la_symbol_ptr",
170                            MachO::S_LAZY_SYMBOL_POINTERS,
171                            SectionKind::getMetadata());
172   NonLazySymbolPointerSection
173     = Ctx->getMachOSection("__DATA", "__nl_symbol_ptr",
174                            MachO::S_NON_LAZY_SYMBOL_POINTERS,
175                            SectionKind::getMetadata());
176 
177   ThreadLocalPointerSection
178     = Ctx->getMachOSection("__DATA", "__thread_ptr",
179                            MachO::S_THREAD_LOCAL_VARIABLE_POINTERS,
180                            SectionKind::getMetadata());
181 
182   // Exception Handling.
183   LSDASection = Ctx->getMachOSection("__TEXT", "__gcc_except_tab", 0,
184                                      SectionKind::getReadOnlyWithRel());
185 
186   COFFDebugSymbolsSection = nullptr;
187   COFFDebugTypesSection = nullptr;
188 
189   if (useCompactUnwind(T)) {
190     CompactUnwindSection =
191         Ctx->getMachOSection("__LD", "__compact_unwind", MachO::S_ATTR_DEBUG,
192                              SectionKind::getReadOnly());
193 
194     if (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86)
195       CompactUnwindDwarfEHFrameOnly = 0x04000000;  // UNWIND_X86_64_MODE_DWARF
196     else if (T.getArch() == Triple::aarch64)
197       CompactUnwindDwarfEHFrameOnly = 0x03000000;  // UNWIND_ARM64_MODE_DWARF
198     else if (T.getArch() == Triple::arm || T.getArch() == Triple::thumb)
199       CompactUnwindDwarfEHFrameOnly = 0x04000000;  // UNWIND_ARM_MODE_DWARF
200   }
201 
202   // Debug Information.
203   DwarfAccelNamesSection =
204       Ctx->getMachOSection("__DWARF", "__apple_names", MachO::S_ATTR_DEBUG,
205                            SectionKind::getMetadata(), "names_begin");
206   DwarfAccelObjCSection =
207       Ctx->getMachOSection("__DWARF", "__apple_objc", MachO::S_ATTR_DEBUG,
208                            SectionKind::getMetadata(), "objc_begin");
209   // 16 character section limit...
210   DwarfAccelNamespaceSection =
211       Ctx->getMachOSection("__DWARF", "__apple_namespac", MachO::S_ATTR_DEBUG,
212                            SectionKind::getMetadata(), "namespac_begin");
213   DwarfAccelTypesSection =
214       Ctx->getMachOSection("__DWARF", "__apple_types", MachO::S_ATTR_DEBUG,
215                            SectionKind::getMetadata(), "types_begin");
216 
217   DwarfSwiftASTSection =
218       Ctx->getMachOSection("__DWARF", "__swift_ast", MachO::S_ATTR_DEBUG,
219                            SectionKind::getMetadata());
220 
221   DwarfAbbrevSection =
222       Ctx->getMachOSection("__DWARF", "__debug_abbrev", MachO::S_ATTR_DEBUG,
223                            SectionKind::getMetadata(), "section_abbrev");
224   DwarfInfoSection =
225       Ctx->getMachOSection("__DWARF", "__debug_info", MachO::S_ATTR_DEBUG,
226                            SectionKind::getMetadata(), "section_info");
227   DwarfLineSection =
228       Ctx->getMachOSection("__DWARF", "__debug_line", MachO::S_ATTR_DEBUG,
229                            SectionKind::getMetadata(), "section_line");
230   DwarfFrameSection =
231       Ctx->getMachOSection("__DWARF", "__debug_frame", MachO::S_ATTR_DEBUG,
232                            SectionKind::getMetadata());
233   DwarfPubNamesSection =
234       Ctx->getMachOSection("__DWARF", "__debug_pubnames", MachO::S_ATTR_DEBUG,
235                            SectionKind::getMetadata());
236   DwarfPubTypesSection =
237       Ctx->getMachOSection("__DWARF", "__debug_pubtypes", MachO::S_ATTR_DEBUG,
238                            SectionKind::getMetadata());
239   DwarfGnuPubNamesSection =
240       Ctx->getMachOSection("__DWARF", "__debug_gnu_pubn", MachO::S_ATTR_DEBUG,
241                            SectionKind::getMetadata());
242   DwarfGnuPubTypesSection =
243       Ctx->getMachOSection("__DWARF", "__debug_gnu_pubt", MachO::S_ATTR_DEBUG,
244                            SectionKind::getMetadata());
245   DwarfStrSection =
246       Ctx->getMachOSection("__DWARF", "__debug_str", MachO::S_ATTR_DEBUG,
247                            SectionKind::getMetadata(), "info_string");
248   DwarfStrOffSection =
249       Ctx->getMachOSection("__DWARF", "__debug_str_offs", MachO::S_ATTR_DEBUG,
250                            SectionKind::getMetadata(), "section_str_off");
251   DwarfLocSection =
252       Ctx->getMachOSection("__DWARF", "__debug_loc", MachO::S_ATTR_DEBUG,
253                            SectionKind::getMetadata(), "section_debug_loc");
254   DwarfARangesSection =
255       Ctx->getMachOSection("__DWARF", "__debug_aranges", MachO::S_ATTR_DEBUG,
256                            SectionKind::getMetadata());
257   DwarfRangesSection =
258       Ctx->getMachOSection("__DWARF", "__debug_ranges", MachO::S_ATTR_DEBUG,
259                            SectionKind::getMetadata(), "debug_range");
260   DwarfMacinfoSection =
261       Ctx->getMachOSection("__DWARF", "__debug_macinfo", MachO::S_ATTR_DEBUG,
262                            SectionKind::getMetadata(), "debug_macinfo");
263   DwarfDebugInlineSection =
264       Ctx->getMachOSection("__DWARF", "__debug_inlined", MachO::S_ATTR_DEBUG,
265                            SectionKind::getMetadata());
266   DwarfCUIndexSection =
267       Ctx->getMachOSection("__DWARF", "__debug_cu_index", MachO::S_ATTR_DEBUG,
268                            SectionKind::getMetadata());
269   DwarfTUIndexSection =
270       Ctx->getMachOSection("__DWARF", "__debug_tu_index", MachO::S_ATTR_DEBUG,
271                            SectionKind::getMetadata());
272   StackMapSection = Ctx->getMachOSection("__LLVM_STACKMAPS", "__llvm_stackmaps",
273                                          0, SectionKind::getMetadata());
274 
275   FaultMapSection = Ctx->getMachOSection("__LLVM_FAULTMAPS", "__llvm_faultmaps",
276                                          0, SectionKind::getMetadata());
277 
278   TLSExtraDataSection = TLSTLVSection;
279 }
280 
281 void MCObjectFileInfo::initELFMCObjectFileInfo(const Triple &T, bool Large) {
282   switch (T.getArch()) {
283   case Triple::mips:
284   case Triple::mipsel:
285     FDECFIEncoding = dwarf::DW_EH_PE_sdata4;
286     break;
287   case Triple::mips64:
288   case Triple::mips64el:
289     FDECFIEncoding = dwarf::DW_EH_PE_sdata8;
290     break;
291   case Triple::x86_64:
292     FDECFIEncoding = dwarf::DW_EH_PE_pcrel |
293                      (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
294     break;
295   case Triple::bpfel:
296   case Triple::bpfeb:
297     FDECFIEncoding = dwarf::DW_EH_PE_sdata8;
298     break;
299   default:
300     FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
301     break;
302   }
303 
304   switch (T.getArch()) {
305   case Triple::arm:
306   case Triple::armeb:
307   case Triple::thumb:
308   case Triple::thumbeb:
309     if (Ctx->getAsmInfo()->getExceptionHandlingType() == ExceptionHandling::ARM)
310       break;
311     // Fallthrough if not using EHABI
312     LLVM_FALLTHROUGH;
313   case Triple::ppc:
314   case Triple::x86:
315     PersonalityEncoding = PositionIndependent
316                               ? dwarf::DW_EH_PE_indirect |
317                                     dwarf::DW_EH_PE_pcrel |
318                                     dwarf::DW_EH_PE_sdata4
319                               : dwarf::DW_EH_PE_absptr;
320     LSDAEncoding = PositionIndependent
321                        ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4
322                        : dwarf::DW_EH_PE_absptr;
323     TTypeEncoding = PositionIndependent
324                         ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
325                               dwarf::DW_EH_PE_sdata4
326                         : dwarf::DW_EH_PE_absptr;
327     break;
328   case Triple::x86_64:
329     if (PositionIndependent) {
330       PersonalityEncoding =
331           dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
332           (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
333       LSDAEncoding = dwarf::DW_EH_PE_pcrel |
334                      (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
335       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
336                       (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
337     } else {
338       PersonalityEncoding =
339           Large ? dwarf::DW_EH_PE_absptr : dwarf::DW_EH_PE_udata4;
340       LSDAEncoding = Large ? dwarf::DW_EH_PE_absptr : dwarf::DW_EH_PE_udata4;
341       TTypeEncoding = Large ? dwarf::DW_EH_PE_absptr : dwarf::DW_EH_PE_udata4;
342     }
343     break;
344   case Triple::hexagon:
345     PersonalityEncoding = dwarf::DW_EH_PE_absptr;
346     LSDAEncoding = dwarf::DW_EH_PE_absptr;
347     FDECFIEncoding = dwarf::DW_EH_PE_absptr;
348     TTypeEncoding = dwarf::DW_EH_PE_absptr;
349     if (PositionIndependent) {
350       PersonalityEncoding |= dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel;
351       LSDAEncoding |= dwarf::DW_EH_PE_pcrel;
352       FDECFIEncoding |= dwarf::DW_EH_PE_pcrel;
353       TTypeEncoding |= dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel;
354     }
355     break;
356   case Triple::aarch64:
357   case Triple::aarch64_be:
358     // The small model guarantees static code/data size < 4GB, but not where it
359     // will be in memory. Most of these could end up >2GB away so even a signed
360     // pc-relative 32-bit address is insufficient, theoretically.
361     if (PositionIndependent) {
362       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
363         dwarf::DW_EH_PE_sdata8;
364       LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8;
365       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
366         dwarf::DW_EH_PE_sdata8;
367     } else {
368       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
369       LSDAEncoding = dwarf::DW_EH_PE_absptr;
370       TTypeEncoding = dwarf::DW_EH_PE_absptr;
371     }
372     break;
373   case Triple::lanai:
374     LSDAEncoding = dwarf::DW_EH_PE_absptr;
375     PersonalityEncoding = dwarf::DW_EH_PE_absptr;
376     TTypeEncoding = dwarf::DW_EH_PE_absptr;
377     break;
378   case Triple::mips:
379   case Triple::mipsel:
380   case Triple::mips64:
381   case Triple::mips64el:
382     // MIPS uses indirect pointer to refer personality functions and types, so
383     // that the eh_frame section can be read-only. DW.ref.personality will be
384     // generated for relocation.
385     PersonalityEncoding = dwarf::DW_EH_PE_indirect;
386     // FIXME: The N64 ABI probably ought to use DW_EH_PE_sdata8 but we can't
387     //        identify N64 from just a triple.
388     TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
389                     dwarf::DW_EH_PE_sdata4;
390     // We don't support PC-relative LSDA references in GAS so we use the default
391     // DW_EH_PE_absptr for those.
392 
393     // FreeBSD must be explicit about the data size and using pcrel since it's
394     // assembler/linker won't do the automatic conversion that the Linux tools
395     // do.
396     if (T.isOSFreeBSD()) {
397       PersonalityEncoding |= dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
398       LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
399     }
400     break;
401   case Triple::ppc64:
402   case Triple::ppc64le:
403     PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
404       dwarf::DW_EH_PE_udata8;
405     LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8;
406     TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
407       dwarf::DW_EH_PE_udata8;
408     break;
409   case Triple::sparcel:
410   case Triple::sparc:
411     if (PositionIndependent) {
412       LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
413       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
414         dwarf::DW_EH_PE_sdata4;
415       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
416         dwarf::DW_EH_PE_sdata4;
417     } else {
418       LSDAEncoding = dwarf::DW_EH_PE_absptr;
419       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
420       TTypeEncoding = dwarf::DW_EH_PE_absptr;
421     }
422     break;
423   case Triple::sparcv9:
424     LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
425     if (PositionIndependent) {
426       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
427         dwarf::DW_EH_PE_sdata4;
428       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
429         dwarf::DW_EH_PE_sdata4;
430     } else {
431       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
432       TTypeEncoding = dwarf::DW_EH_PE_absptr;
433     }
434     break;
435   case Triple::systemz:
436     // All currently-defined code models guarantee that 4-byte PC-relative
437     // values will be in range.
438     if (PositionIndependent) {
439       PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
440         dwarf::DW_EH_PE_sdata4;
441       LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
442       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
443         dwarf::DW_EH_PE_sdata4;
444     } else {
445       PersonalityEncoding = dwarf::DW_EH_PE_absptr;
446       LSDAEncoding = dwarf::DW_EH_PE_absptr;
447       TTypeEncoding = dwarf::DW_EH_PE_absptr;
448     }
449     break;
450   default:
451     break;
452   }
453 
454   unsigned EHSectionType = T.getArch() == Triple::x86_64
455                                ? ELF::SHT_X86_64_UNWIND
456                                : ELF::SHT_PROGBITS;
457 
458   // Solaris requires different flags for .eh_frame to seemingly every other
459   // platform.
460   unsigned EHSectionFlags = ELF::SHF_ALLOC;
461   if (T.isOSSolaris() && T.getArch() != Triple::x86_64)
462     EHSectionFlags |= ELF::SHF_WRITE;
463 
464   // ELF
465   BSSSection = Ctx->getELFSection(".bss", ELF::SHT_NOBITS,
466                                   ELF::SHF_WRITE | ELF::SHF_ALLOC);
467 
468   TextSection = Ctx->getELFSection(".text", ELF::SHT_PROGBITS,
469                                    ELF::SHF_EXECINSTR | ELF::SHF_ALLOC);
470 
471   DataSection = Ctx->getELFSection(".data", ELF::SHT_PROGBITS,
472                                    ELF::SHF_WRITE | ELF::SHF_ALLOC);
473 
474   ReadOnlySection =
475       Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);
476 
477   TLSDataSection =
478       Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS,
479                          ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE);
480 
481   TLSBSSSection = Ctx->getELFSection(
482       ".tbss", ELF::SHT_NOBITS, ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE);
483 
484   DataRelROSection = Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS,
485                                         ELF::SHF_ALLOC | ELF::SHF_WRITE);
486 
487   MergeableConst4Section =
488       Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS,
489                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 4, "");
490 
491   MergeableConst8Section =
492       Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS,
493                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 8, "");
494 
495   MergeableConst16Section =
496       Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS,
497                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 16, "");
498 
499   MergeableConst32Section =
500       Ctx->getELFSection(".rodata.cst32", ELF::SHT_PROGBITS,
501                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 32, "");
502 
503   // Exception Handling Sections.
504 
505   // FIXME: We're emitting LSDA info into a readonly section on ELF, even though
506   // it contains relocatable pointers.  In PIC mode, this is probably a big
507   // runtime hit for C++ apps.  Either the contents of the LSDA need to be
508   // adjusted or this should be a data section.
509   LSDASection = Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS,
510                                    ELF::SHF_ALLOC);
511 
512   COFFDebugSymbolsSection = nullptr;
513   COFFDebugTypesSection = nullptr;
514 
515   unsigned DebugSecType = ELF::SHT_PROGBITS;
516 
517   // MIPS .debug_* sections should have SHT_MIPS_DWARF section type
518   // to distinguish among sections contain DWARF and ECOFF debug formats.
519   // Sections with ECOFF debug format are obsoleted and marked by SHT_PROGBITS.
520   if (T.getArch() == Triple::mips || T.getArch() == Triple::mipsel ||
521       T.getArch() == Triple::mips64 || T.getArch() == Triple::mips64el)
522     DebugSecType = ELF::SHT_MIPS_DWARF;
523 
524   // Debug Info Sections.
525   DwarfAbbrevSection =
526       Ctx->getELFSection(".debug_abbrev", DebugSecType, 0);
527   DwarfInfoSection = Ctx->getELFSection(".debug_info", DebugSecType, 0);
528   DwarfLineSection = Ctx->getELFSection(".debug_line", DebugSecType, 0);
529   DwarfFrameSection = Ctx->getELFSection(".debug_frame", DebugSecType, 0);
530   DwarfPubNamesSection =
531       Ctx->getELFSection(".debug_pubnames", DebugSecType, 0);
532   DwarfPubTypesSection =
533       Ctx->getELFSection(".debug_pubtypes", DebugSecType, 0);
534   DwarfGnuPubNamesSection =
535       Ctx->getELFSection(".debug_gnu_pubnames", DebugSecType, 0);
536   DwarfGnuPubTypesSection =
537       Ctx->getELFSection(".debug_gnu_pubtypes", DebugSecType, 0);
538   DwarfStrSection =
539       Ctx->getELFSection(".debug_str", DebugSecType,
540                          ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, "");
541   DwarfLocSection = Ctx->getELFSection(".debug_loc", DebugSecType, 0);
542   DwarfARangesSection =
543       Ctx->getELFSection(".debug_aranges", DebugSecType, 0);
544   DwarfRangesSection =
545       Ctx->getELFSection(".debug_ranges", DebugSecType, 0);
546   DwarfMacinfoSection =
547       Ctx->getELFSection(".debug_macinfo", DebugSecType, 0);
548 
549   // DWARF5 Experimental Debug Info
550 
551   // Accelerator Tables
552   DwarfAccelNamesSection =
553       Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0);
554   DwarfAccelObjCSection =
555       Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0);
556   DwarfAccelNamespaceSection =
557       Ctx->getELFSection(".apple_namespaces", ELF::SHT_PROGBITS, 0);
558   DwarfAccelTypesSection =
559       Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0);
560 
561   // String Offset and Address Sections
562   DwarfStrOffSection =
563       Ctx->getELFSection(".debug_str_offsets", DebugSecType, 0);
564   DwarfAddrSection = Ctx->getELFSection(".debug_addr", DebugSecType, 0);
565 
566   // Fission Sections
567   DwarfInfoDWOSection =
568       Ctx->getELFSection(".debug_info.dwo", DebugSecType, 0);
569   DwarfTypesDWOSection =
570       Ctx->getELFSection(".debug_types.dwo", DebugSecType, 0);
571   DwarfAbbrevDWOSection =
572       Ctx->getELFSection(".debug_abbrev.dwo", DebugSecType, 0);
573   DwarfStrDWOSection =
574       Ctx->getELFSection(".debug_str.dwo", DebugSecType,
575                          ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, "");
576   DwarfLineDWOSection =
577       Ctx->getELFSection(".debug_line.dwo", DebugSecType, 0);
578   DwarfLocDWOSection =
579       Ctx->getELFSection(".debug_loc.dwo", DebugSecType, 0);
580   DwarfStrOffDWOSection =
581       Ctx->getELFSection(".debug_str_offsets.dwo", DebugSecType, 0);
582 
583   // DWP Sections
584   DwarfCUIndexSection =
585       Ctx->getELFSection(".debug_cu_index", DebugSecType, 0);
586   DwarfTUIndexSection =
587       Ctx->getELFSection(".debug_tu_index", DebugSecType, 0);
588 
589   StackMapSection =
590       Ctx->getELFSection(".llvm_stackmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);
591 
592   FaultMapSection =
593       Ctx->getELFSection(".llvm_faultmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);
594 
595   EHFrameSection =
596       Ctx->getELFSection(".eh_frame", EHSectionType, EHSectionFlags);
597 
598   StackSizesSection = Ctx->getELFSection(".stack_sizes", ELF::SHT_PROGBITS, 0);
599 }
600 
601 void MCObjectFileInfo::initCOFFMCObjectFileInfo(const Triple &T) {
602   EHFrameSection = Ctx->getCOFFSection(
603       ".eh_frame", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
604                        COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE,
605       SectionKind::getData());
606 
607   // Set the `IMAGE_SCN_MEM_16BIT` flag when compiling for thumb mode.  This is
608   // used to indicate to the linker that the text segment contains thumb instructions
609   // and to set the ISA selection bit for calls accordingly.
610   const bool IsThumb = T.getArch() == Triple::thumb;
611 
612   CommDirectiveSupportsAlignment = true;
613 
614   // COFF
615   BSSSection = Ctx->getCOFFSection(
616       ".bss", COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA |
617                   COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE,
618       SectionKind::getBSS());
619   TextSection = Ctx->getCOFFSection(
620       ".text",
621       (IsThumb ? COFF::IMAGE_SCN_MEM_16BIT : (COFF::SectionCharacteristics)0) |
622           COFF::IMAGE_SCN_CNT_CODE | COFF::IMAGE_SCN_MEM_EXECUTE |
623           COFF::IMAGE_SCN_MEM_READ,
624       SectionKind::getText());
625   DataSection = Ctx->getCOFFSection(
626       ".data", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ |
627                    COFF::IMAGE_SCN_MEM_WRITE,
628       SectionKind::getData());
629   ReadOnlySection = Ctx->getCOFFSection(
630       ".rdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
631       SectionKind::getReadOnly());
632 
633   // FIXME: We're emitting LSDA info into a readonly section on COFF, even
634   // though it contains relocatable pointers.  In PIC mode, this is probably a
635   // big runtime hit for C++ apps.  Either the contents of the LSDA need to be
636   // adjusted or this should be a data section.
637   if (T.getArch() == Triple::x86_64) {
638     // On Windows 64 with SEH, the LSDA is emitted into the .xdata section
639     LSDASection = nullptr;
640   } else {
641     LSDASection = Ctx->getCOFFSection(".gcc_except_table",
642                                       COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
643                                           COFF::IMAGE_SCN_MEM_READ,
644                                       SectionKind::getReadOnly());
645   }
646 
647   // Debug info.
648   COFFDebugSymbolsSection =
649       Ctx->getCOFFSection(".debug$S", (COFF::IMAGE_SCN_MEM_DISCARDABLE |
650                                        COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
651                                        COFF::IMAGE_SCN_MEM_READ),
652                           SectionKind::getMetadata());
653   COFFDebugTypesSection =
654       Ctx->getCOFFSection(".debug$T", (COFF::IMAGE_SCN_MEM_DISCARDABLE |
655                                        COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
656                                        COFF::IMAGE_SCN_MEM_READ),
657                           SectionKind::getMetadata());
658 
659   DwarfAbbrevSection = Ctx->getCOFFSection(
660       ".debug_abbrev",
661       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
662           COFF::IMAGE_SCN_MEM_READ,
663       SectionKind::getMetadata(), "section_abbrev");
664   DwarfInfoSection = Ctx->getCOFFSection(
665       ".debug_info",
666       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
667           COFF::IMAGE_SCN_MEM_READ,
668       SectionKind::getMetadata(), "section_info");
669   DwarfLineSection = Ctx->getCOFFSection(
670       ".debug_line",
671       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
672           COFF::IMAGE_SCN_MEM_READ,
673       SectionKind::getMetadata(), "section_line");
674 
675   DwarfFrameSection = Ctx->getCOFFSection(
676       ".debug_frame",
677       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
678           COFF::IMAGE_SCN_MEM_READ,
679       SectionKind::getMetadata());
680   DwarfPubNamesSection = Ctx->getCOFFSection(
681       ".debug_pubnames",
682       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
683           COFF::IMAGE_SCN_MEM_READ,
684       SectionKind::getMetadata());
685   DwarfPubTypesSection = Ctx->getCOFFSection(
686       ".debug_pubtypes",
687       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
688           COFF::IMAGE_SCN_MEM_READ,
689       SectionKind::getMetadata());
690   DwarfGnuPubNamesSection = Ctx->getCOFFSection(
691       ".debug_gnu_pubnames",
692       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
693           COFF::IMAGE_SCN_MEM_READ,
694       SectionKind::getMetadata());
695   DwarfGnuPubTypesSection = Ctx->getCOFFSection(
696       ".debug_gnu_pubtypes",
697       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
698           COFF::IMAGE_SCN_MEM_READ,
699       SectionKind::getMetadata());
700   DwarfStrSection = Ctx->getCOFFSection(
701       ".debug_str",
702       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
703           COFF::IMAGE_SCN_MEM_READ,
704       SectionKind::getMetadata(), "info_string");
705   DwarfStrOffSection = Ctx->getCOFFSection(
706       ".debug_str_offsets",
707       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
708           COFF::IMAGE_SCN_MEM_READ,
709       SectionKind::getMetadata(), "section_str_off");
710   DwarfLocSection = Ctx->getCOFFSection(
711       ".debug_loc",
712       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
713           COFF::IMAGE_SCN_MEM_READ,
714       SectionKind::getMetadata(), "section_debug_loc");
715   DwarfARangesSection = Ctx->getCOFFSection(
716       ".debug_aranges",
717       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
718           COFF::IMAGE_SCN_MEM_READ,
719       SectionKind::getMetadata());
720   DwarfRangesSection = Ctx->getCOFFSection(
721       ".debug_ranges",
722       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
723           COFF::IMAGE_SCN_MEM_READ,
724       SectionKind::getMetadata(), "debug_range");
725   DwarfMacinfoSection = Ctx->getCOFFSection(
726       ".debug_macinfo",
727       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
728           COFF::IMAGE_SCN_MEM_READ,
729       SectionKind::getMetadata(), "debug_macinfo");
730   DwarfInfoDWOSection = Ctx->getCOFFSection(
731       ".debug_info.dwo",
732       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
733           COFF::IMAGE_SCN_MEM_READ,
734       SectionKind::getMetadata(), "section_info_dwo");
735   DwarfTypesDWOSection = Ctx->getCOFFSection(
736       ".debug_types.dwo",
737       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
738           COFF::IMAGE_SCN_MEM_READ,
739       SectionKind::getMetadata(), "section_types_dwo");
740   DwarfAbbrevDWOSection = Ctx->getCOFFSection(
741       ".debug_abbrev.dwo",
742       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
743           COFF::IMAGE_SCN_MEM_READ,
744       SectionKind::getMetadata(), "section_abbrev_dwo");
745   DwarfStrDWOSection = Ctx->getCOFFSection(
746       ".debug_str.dwo",
747       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
748           COFF::IMAGE_SCN_MEM_READ,
749       SectionKind::getMetadata(), "skel_string");
750   DwarfLineDWOSection = Ctx->getCOFFSection(
751       ".debug_line.dwo",
752       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
753           COFF::IMAGE_SCN_MEM_READ,
754       SectionKind::getMetadata());
755   DwarfLocDWOSection = Ctx->getCOFFSection(
756       ".debug_loc.dwo",
757       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
758           COFF::IMAGE_SCN_MEM_READ,
759       SectionKind::getMetadata(), "skel_loc");
760   DwarfStrOffDWOSection = Ctx->getCOFFSection(
761       ".debug_str_offsets.dwo",
762       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
763           COFF::IMAGE_SCN_MEM_READ,
764       SectionKind::getMetadata(), "section_str_off_dwo");
765   DwarfAddrSection = Ctx->getCOFFSection(
766       ".debug_addr",
767       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
768           COFF::IMAGE_SCN_MEM_READ,
769       SectionKind::getMetadata(), "addr_sec");
770   DwarfCUIndexSection = Ctx->getCOFFSection(
771       ".debug_cu_index",
772       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
773           COFF::IMAGE_SCN_MEM_READ,
774       SectionKind::getMetadata());
775   DwarfTUIndexSection = Ctx->getCOFFSection(
776       ".debug_tu_index",
777       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
778           COFF::IMAGE_SCN_MEM_READ,
779       SectionKind::getMetadata());
780   DwarfAccelNamesSection = Ctx->getCOFFSection(
781       ".apple_names",
782       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
783           COFF::IMAGE_SCN_MEM_READ,
784       SectionKind::getMetadata(), "names_begin");
785   DwarfAccelNamespaceSection = Ctx->getCOFFSection(
786       ".apple_namespaces",
787       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
788           COFF::IMAGE_SCN_MEM_READ,
789       SectionKind::getMetadata(), "namespac_begin");
790   DwarfAccelTypesSection = Ctx->getCOFFSection(
791       ".apple_types",
792       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
793           COFF::IMAGE_SCN_MEM_READ,
794       SectionKind::getMetadata(), "types_begin");
795   DwarfAccelObjCSection = Ctx->getCOFFSection(
796       ".apple_objc",
797       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
798           COFF::IMAGE_SCN_MEM_READ,
799       SectionKind::getMetadata(), "objc_begin");
800 
801   DrectveSection = Ctx->getCOFFSection(
802       ".drectve", COFF::IMAGE_SCN_LNK_INFO | COFF::IMAGE_SCN_LNK_REMOVE,
803       SectionKind::getMetadata());
804 
805   PDataSection = Ctx->getCOFFSection(
806       ".pdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
807       SectionKind::getData());
808 
809   XDataSection = Ctx->getCOFFSection(
810       ".xdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
811       SectionKind::getData());
812 
813   SXDataSection = Ctx->getCOFFSection(".sxdata", COFF::IMAGE_SCN_LNK_INFO,
814                                       SectionKind::getMetadata());
815 
816   TLSDataSection = Ctx->getCOFFSection(
817       ".tls$", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ |
818                    COFF::IMAGE_SCN_MEM_WRITE,
819       SectionKind::getData());
820 
821   StackMapSection = Ctx->getCOFFSection(".llvm_stackmaps",
822                                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
823                                             COFF::IMAGE_SCN_MEM_READ,
824                                         SectionKind::getReadOnly());
825 }
826 
827 void MCObjectFileInfo::initWasmMCObjectFileInfo(const Triple &T) {
828   // TODO: Set the section types and flags.
829   TextSection = Ctx->getWasmSection(".text", SectionKind::getText());
830   DataSection = Ctx->getWasmSection(".data", SectionKind::getData());
831 
832   // TODO: Set the section types and flags.
833   DwarfLineSection = Ctx->getWasmSection(".debug_line", SectionKind::getMetadata());
834   DwarfStrSection = Ctx->getWasmSection(".debug_str", SectionKind::getMetadata());
835   DwarfLocSection = Ctx->getWasmSection(".debug_loc", SectionKind::getMetadata());
836   DwarfAbbrevSection = Ctx->getWasmSection(".debug_abbrev", SectionKind::getMetadata(), "section_abbrev");
837   DwarfARangesSection = Ctx->getWasmSection(".debug_aranges", SectionKind::getMetadata());
838   DwarfRangesSection = Ctx->getWasmSection(".debug_ranges", SectionKind::getMetadata(), "debug_range");
839   DwarfMacinfoSection = Ctx->getWasmSection(".debug_macinfo", SectionKind::getMetadata(), "debug_macinfo");
840   DwarfAddrSection = Ctx->getWasmSection(".debug_addr", SectionKind::getMetadata());
841   DwarfCUIndexSection = Ctx->getWasmSection(".debug_cu_index", SectionKind::getMetadata());
842   DwarfTUIndexSection = Ctx->getWasmSection(".debug_tu_index", SectionKind::getMetadata());
843   DwarfInfoSection = Ctx->getWasmSection(".debug_info", SectionKind::getMetadata(), "section_info");
844   DwarfFrameSection = Ctx->getWasmSection(".debug_frame", SectionKind::getMetadata());
845   DwarfPubNamesSection = Ctx->getWasmSection(".debug_pubnames", SectionKind::getMetadata());
846   DwarfPubTypesSection = Ctx->getWasmSection(".debug_pubtypes", SectionKind::getMetadata());
847 
848   // TODO: Define more sections.
849 }
850 
851 void MCObjectFileInfo::InitMCObjectFileInfo(const Triple &TheTriple, bool PIC,
852                                             MCContext &ctx,
853                                             bool LargeCodeModel) {
854   PositionIndependent = PIC;
855   Ctx = &ctx;
856 
857   // Common.
858   CommDirectiveSupportsAlignment = true;
859   SupportsWeakOmittedEHFrame = true;
860   SupportsCompactUnwindWithoutEHFrame = false;
861   OmitDwarfIfHaveCompactUnwind = false;
862 
863   PersonalityEncoding = LSDAEncoding = FDECFIEncoding = TTypeEncoding =
864       dwarf::DW_EH_PE_absptr;
865 
866   CompactUnwindDwarfEHFrameOnly = 0;
867 
868   EHFrameSection = nullptr;             // Created on demand.
869   CompactUnwindSection = nullptr;       // Used only by selected targets.
870   DwarfAccelNamesSection = nullptr;     // Used only by selected targets.
871   DwarfAccelObjCSection = nullptr;      // Used only by selected targets.
872   DwarfAccelNamespaceSection = nullptr; // Used only by selected targets.
873   DwarfAccelTypesSection = nullptr;     // Used only by selected targets.
874 
875   TT = TheTriple;
876 
877   switch (TT.getObjectFormat()) {
878   case Triple::MachO:
879     Env = IsMachO;
880     initMachOMCObjectFileInfo(TT);
881     break;
882   case Triple::COFF:
883     if (!TT.isOSWindows())
884       report_fatal_error(
885           "Cannot initialize MC for non-Windows COFF object files.");
886 
887     Env = IsCOFF;
888     initCOFFMCObjectFileInfo(TT);
889     break;
890   case Triple::ELF:
891     Env = IsELF;
892     initELFMCObjectFileInfo(TT, LargeCodeModel);
893     break;
894   case Triple::Wasm:
895     Env = IsWasm;
896     initWasmMCObjectFileInfo(TT);
897     break;
898   case Triple::UnknownObjectFormat:
899     report_fatal_error("Cannot initialize MC for unknown object file format.");
900     break;
901   }
902 }
903 
904 MCSection *MCObjectFileInfo::getDwarfTypesSection(uint64_t Hash) const {
905   return Ctx->getELFSection(".debug_types", ELF::SHT_PROGBITS, ELF::SHF_GROUP,
906                             0, utostr(Hash));
907 }
908