1 //===-- MCObjectFileInfo.cpp - Object File Information --------------------===//
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 #include "llvm/MC/MCObjectFileInfo.h"
10 #include "llvm/ADT/StringExtras.h"
11 #include "llvm/ADT/Triple.h"
12 #include "llvm/BinaryFormat/COFF.h"
13 #include "llvm/BinaryFormat/ELF.h"
14 #include "llvm/BinaryFormat/Wasm.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/MCSectionGOFF.h"
21 #include "llvm/MC/MCSectionMachO.h"
22 #include "llvm/MC/MCSectionSPIRV.h"
23 #include "llvm/MC/MCSectionWasm.h"
24 #include "llvm/MC/MCSectionXCOFF.h"
25 #include "llvm/Support/Casting.h"
26 
27 using namespace llvm;
28 
29 static bool useCompactUnwind(const Triple &T) {
30   // Only on darwin.
31   if (!T.isOSDarwin())
32     return false;
33 
34   // aarch64 always has it.
35   if (T.getArch() == Triple::aarch64 || T.getArch() == Triple::aarch64_32)
36     return true;
37 
38   // armv7k always has it.
39   if (T.isWatchABI())
40     return true;
41 
42   // Use it on newer version of OS X.
43   if (T.isMacOSX() && !T.isMacOSXVersionLT(10, 6))
44     return true;
45 
46   // And the iOS simulator.
47   if (T.isiOS() && T.isX86())
48     return true;
49 
50   return false;
51 }
52 
53 void MCObjectFileInfo::initMachOMCObjectFileInfo(const Triple &T) {
54   // MachO
55   SupportsWeakOmittedEHFrame = false;
56 
57   EHFrameSection = Ctx->getMachOSection(
58       "__TEXT", "__eh_frame",
59       MachO::S_COALESCED | MachO::S_ATTR_NO_TOC |
60           MachO::S_ATTR_STRIP_STATIC_SYMS | MachO::S_ATTR_LIVE_SUPPORT,
61       SectionKind::getReadOnly());
62 
63   if (T.isOSDarwin() &&
64       (T.getArch() == Triple::aarch64 || T.getArch() == Triple::aarch64_32))
65     SupportsCompactUnwindWithoutEHFrame = true;
66 
67   if (T.isWatchABI())
68     OmitDwarfIfHaveCompactUnwind = true;
69 
70   FDECFIEncoding = dwarf::DW_EH_PE_pcrel;
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   ConstDataSection  // .const_data
139     = Ctx->getMachOSection("__DATA", "__const", 0,
140                            SectionKind::getReadOnlyWithRel());
141 
142   if (ArchTy == Triple::ppc || ArchTy == Triple::ppc64) {
143     TextCoalSection
144       = Ctx->getMachOSection("__TEXT", "__textcoal_nt",
145                              MachO::S_COALESCED |
146                              MachO::S_ATTR_PURE_INSTRUCTIONS,
147                              SectionKind::getText());
148     ConstTextCoalSection
149       = Ctx->getMachOSection("__TEXT", "__const_coal",
150                              MachO::S_COALESCED,
151                              SectionKind::getReadOnly());
152     DataCoalSection = Ctx->getMachOSection(
153         "__DATA", "__datacoal_nt", MachO::S_COALESCED, SectionKind::getData());
154     ConstDataCoalSection = DataCoalSection;
155   } else {
156     TextCoalSection = TextSection;
157     ConstTextCoalSection = ReadOnlySection;
158     DataCoalSection = DataSection;
159     ConstDataCoalSection = ConstDataSection;
160   }
161 
162   DataCommonSection
163     = Ctx->getMachOSection("__DATA","__common",
164                            MachO::S_ZEROFILL,
165                            SectionKind::getBSS());
166   DataBSSSection
167     = Ctx->getMachOSection("__DATA","__bss", MachO::S_ZEROFILL,
168                            SectionKind::getBSS());
169 
170 
171   LazySymbolPointerSection
172     = Ctx->getMachOSection("__DATA", "__la_symbol_ptr",
173                            MachO::S_LAZY_SYMBOL_POINTERS,
174                            SectionKind::getMetadata());
175   NonLazySymbolPointerSection
176     = Ctx->getMachOSection("__DATA", "__nl_symbol_ptr",
177                            MachO::S_NON_LAZY_SYMBOL_POINTERS,
178                            SectionKind::getMetadata());
179 
180   ThreadLocalPointerSection
181     = Ctx->getMachOSection("__DATA", "__thread_ptr",
182                            MachO::S_THREAD_LOCAL_VARIABLE_POINTERS,
183                            SectionKind::getMetadata());
184 
185   AddrSigSection = Ctx->getMachOSection("__DATA", "__llvm_addrsig", 0,
186                                         SectionKind::getData());
187 
188   // Exception Handling.
189   LSDASection = Ctx->getMachOSection("__TEXT", "__gcc_except_tab", 0,
190                                      SectionKind::getReadOnlyWithRel());
191 
192   COFFDebugSymbolsSection = nullptr;
193   COFFDebugTypesSection = nullptr;
194   COFFGlobalTypeHashesSection = nullptr;
195 
196   if (useCompactUnwind(T)) {
197     CompactUnwindSection =
198         Ctx->getMachOSection("__LD", "__compact_unwind", MachO::S_ATTR_DEBUG,
199                              SectionKind::getReadOnly());
200 
201     if (T.isX86())
202       CompactUnwindDwarfEHFrameOnly = 0x04000000;  // UNWIND_X86_64_MODE_DWARF
203     else if (T.getArch() == Triple::aarch64 || T.getArch() == Triple::aarch64_32)
204       CompactUnwindDwarfEHFrameOnly = 0x03000000;  // UNWIND_ARM64_MODE_DWARF
205     else if (T.getArch() == Triple::arm || T.getArch() == Triple::thumb)
206       CompactUnwindDwarfEHFrameOnly = 0x04000000;  // UNWIND_ARM_MODE_DWARF
207   }
208 
209   // Debug Information.
210   DwarfDebugNamesSection =
211       Ctx->getMachOSection("__DWARF", "__debug_names", MachO::S_ATTR_DEBUG,
212                            SectionKind::getMetadata(), "debug_names_begin");
213   DwarfAccelNamesSection =
214       Ctx->getMachOSection("__DWARF", "__apple_names", MachO::S_ATTR_DEBUG,
215                            SectionKind::getMetadata(), "names_begin");
216   DwarfAccelObjCSection =
217       Ctx->getMachOSection("__DWARF", "__apple_objc", MachO::S_ATTR_DEBUG,
218                            SectionKind::getMetadata(), "objc_begin");
219   // 16 character section limit...
220   DwarfAccelNamespaceSection =
221       Ctx->getMachOSection("__DWARF", "__apple_namespac", MachO::S_ATTR_DEBUG,
222                            SectionKind::getMetadata(), "namespac_begin");
223   DwarfAccelTypesSection =
224       Ctx->getMachOSection("__DWARF", "__apple_types", MachO::S_ATTR_DEBUG,
225                            SectionKind::getMetadata(), "types_begin");
226 
227   DwarfSwiftASTSection =
228       Ctx->getMachOSection("__DWARF", "__swift_ast", MachO::S_ATTR_DEBUG,
229                            SectionKind::getMetadata());
230 
231   DwarfAbbrevSection =
232       Ctx->getMachOSection("__DWARF", "__debug_abbrev", MachO::S_ATTR_DEBUG,
233                            SectionKind::getMetadata(), "section_abbrev");
234   DwarfInfoSection =
235       Ctx->getMachOSection("__DWARF", "__debug_info", MachO::S_ATTR_DEBUG,
236                            SectionKind::getMetadata(), "section_info");
237   DwarfLineSection =
238       Ctx->getMachOSection("__DWARF", "__debug_line", MachO::S_ATTR_DEBUG,
239                            SectionKind::getMetadata(), "section_line");
240   DwarfLineStrSection =
241       Ctx->getMachOSection("__DWARF", "__debug_line_str", MachO::S_ATTR_DEBUG,
242                            SectionKind::getMetadata(), "section_line_str");
243   DwarfFrameSection =
244       Ctx->getMachOSection("__DWARF", "__debug_frame", MachO::S_ATTR_DEBUG,
245                            SectionKind::getMetadata());
246   DwarfPubNamesSection =
247       Ctx->getMachOSection("__DWARF", "__debug_pubnames", MachO::S_ATTR_DEBUG,
248                            SectionKind::getMetadata());
249   DwarfPubTypesSection =
250       Ctx->getMachOSection("__DWARF", "__debug_pubtypes", MachO::S_ATTR_DEBUG,
251                            SectionKind::getMetadata());
252   DwarfGnuPubNamesSection =
253       Ctx->getMachOSection("__DWARF", "__debug_gnu_pubn", MachO::S_ATTR_DEBUG,
254                            SectionKind::getMetadata());
255   DwarfGnuPubTypesSection =
256       Ctx->getMachOSection("__DWARF", "__debug_gnu_pubt", MachO::S_ATTR_DEBUG,
257                            SectionKind::getMetadata());
258   DwarfStrSection =
259       Ctx->getMachOSection("__DWARF", "__debug_str", MachO::S_ATTR_DEBUG,
260                            SectionKind::getMetadata(), "info_string");
261   DwarfStrOffSection =
262       Ctx->getMachOSection("__DWARF", "__debug_str_offs", MachO::S_ATTR_DEBUG,
263                            SectionKind::getMetadata(), "section_str_off");
264   DwarfAddrSection =
265       Ctx->getMachOSection("__DWARF", "__debug_addr", MachO::S_ATTR_DEBUG,
266                            SectionKind::getMetadata(), "section_info");
267   DwarfLocSection =
268       Ctx->getMachOSection("__DWARF", "__debug_loc", MachO::S_ATTR_DEBUG,
269                            SectionKind::getMetadata(), "section_debug_loc");
270   DwarfLoclistsSection =
271       Ctx->getMachOSection("__DWARF", "__debug_loclists", MachO::S_ATTR_DEBUG,
272                            SectionKind::getMetadata(), "section_debug_loc");
273 
274   DwarfARangesSection =
275       Ctx->getMachOSection("__DWARF", "__debug_aranges", MachO::S_ATTR_DEBUG,
276                            SectionKind::getMetadata());
277   DwarfRangesSection =
278       Ctx->getMachOSection("__DWARF", "__debug_ranges", MachO::S_ATTR_DEBUG,
279                            SectionKind::getMetadata(), "debug_range");
280   DwarfRnglistsSection =
281       Ctx->getMachOSection("__DWARF", "__debug_rnglists", MachO::S_ATTR_DEBUG,
282                            SectionKind::getMetadata(), "debug_range");
283   DwarfMacinfoSection =
284       Ctx->getMachOSection("__DWARF", "__debug_macinfo", MachO::S_ATTR_DEBUG,
285                            SectionKind::getMetadata(), "debug_macinfo");
286   DwarfMacroSection =
287       Ctx->getMachOSection("__DWARF", "__debug_macro", MachO::S_ATTR_DEBUG,
288                            SectionKind::getMetadata(), "debug_macro");
289   DwarfDebugInlineSection =
290       Ctx->getMachOSection("__DWARF", "__debug_inlined", MachO::S_ATTR_DEBUG,
291                            SectionKind::getMetadata());
292   DwarfCUIndexSection =
293       Ctx->getMachOSection("__DWARF", "__debug_cu_index", MachO::S_ATTR_DEBUG,
294                            SectionKind::getMetadata());
295   DwarfTUIndexSection =
296       Ctx->getMachOSection("__DWARF", "__debug_tu_index", MachO::S_ATTR_DEBUG,
297                            SectionKind::getMetadata());
298   StackMapSection = Ctx->getMachOSection("__LLVM_STACKMAPS", "__llvm_stackmaps",
299                                          0, SectionKind::getMetadata());
300 
301   FaultMapSection = Ctx->getMachOSection("__LLVM_FAULTMAPS", "__llvm_faultmaps",
302                                          0, SectionKind::getMetadata());
303 
304   RemarksSection = Ctx->getMachOSection(
305       "__LLVM", "__remarks", MachO::S_ATTR_DEBUG, SectionKind::getMetadata());
306 
307   // The architecture of dsymutil makes it very difficult to copy the Swift
308   // reflection metadata sections into the __TEXT segment, so dsymutil creates
309   // these sections in the __DWARF segment instead.
310   if (!Ctx->getSwift5ReflectionSegmentName().empty()) {
311 #define HANDLE_SWIFT_SECTION(KIND, MACHO, ELF, COFF)                           \
312   Swift5ReflectionSections                                                     \
313       [llvm::binaryformat::Swift5ReflectionSectionKind::KIND] =                \
314           Ctx->getMachOSection(Ctx->getSwift5ReflectionSegmentName().data(),   \
315                                MACHO, 0, SectionKind::getMetadata());
316 #include "llvm/BinaryFormat/Swift.def"
317   }
318 
319   TLSExtraDataSection = TLSTLVSection;
320 }
321 
322 void MCObjectFileInfo::initELFMCObjectFileInfo(const Triple &T, bool Large) {
323   switch (T.getArch()) {
324   case Triple::mips:
325   case Triple::mipsel:
326   case Triple::mips64:
327   case Triple::mips64el:
328     // We cannot use DW_EH_PE_sdata8 for the large PositionIndependent case
329     // since there is no R_MIPS_PC64 relocation (only a 32-bit version).
330     if (PositionIndependent && !Large)
331       FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
332     else
333       FDECFIEncoding = Ctx->getAsmInfo()->getCodePointerSize() == 4
334                            ? dwarf::DW_EH_PE_sdata4
335                            : dwarf::DW_EH_PE_sdata8;
336     break;
337   case Triple::ppc64:
338   case Triple::ppc64le:
339   case Triple::aarch64:
340   case Triple::aarch64_be:
341   case Triple::x86_64:
342     FDECFIEncoding = dwarf::DW_EH_PE_pcrel |
343                      (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
344     break;
345   case Triple::bpfel:
346   case Triple::bpfeb:
347     FDECFIEncoding = dwarf::DW_EH_PE_sdata8;
348     break;
349   case Triple::hexagon:
350     FDECFIEncoding =
351         PositionIndependent ? dwarf::DW_EH_PE_pcrel : dwarf::DW_EH_PE_absptr;
352     break;
353   default:
354     FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
355     break;
356   }
357 
358   unsigned EHSectionType = T.getArch() == Triple::x86_64
359                                ? ELF::SHT_X86_64_UNWIND
360                                : ELF::SHT_PROGBITS;
361 
362   // Solaris requires different flags for .eh_frame to seemingly every other
363   // platform.
364   unsigned EHSectionFlags = ELF::SHF_ALLOC;
365   if (T.isOSSolaris() && T.getArch() != Triple::x86_64)
366     EHSectionFlags |= ELF::SHF_WRITE;
367 
368   // ELF
369   BSSSection = Ctx->getELFSection(".bss", ELF::SHT_NOBITS,
370                                   ELF::SHF_WRITE | ELF::SHF_ALLOC);
371 
372   TextSection = Ctx->getELFSection(".text", ELF::SHT_PROGBITS,
373                                    ELF::SHF_EXECINSTR | ELF::SHF_ALLOC);
374 
375   DataSection = Ctx->getELFSection(".data", ELF::SHT_PROGBITS,
376                                    ELF::SHF_WRITE | ELF::SHF_ALLOC);
377 
378   ReadOnlySection =
379       Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);
380 
381   TLSDataSection =
382       Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS,
383                          ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE);
384 
385   TLSBSSSection = Ctx->getELFSection(
386       ".tbss", ELF::SHT_NOBITS, ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE);
387 
388   DataRelROSection = Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS,
389                                         ELF::SHF_ALLOC | ELF::SHF_WRITE);
390 
391   MergeableConst4Section =
392       Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS,
393                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 4);
394 
395   MergeableConst8Section =
396       Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS,
397                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 8);
398 
399   MergeableConst16Section =
400       Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS,
401                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 16);
402 
403   MergeableConst32Section =
404       Ctx->getELFSection(".rodata.cst32", ELF::SHT_PROGBITS,
405                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 32);
406 
407   // Exception Handling Sections.
408 
409   // FIXME: We're emitting LSDA info into a readonly section on ELF, even though
410   // it contains relocatable pointers.  In PIC mode, this is probably a big
411   // runtime hit for C++ apps.  Either the contents of the LSDA need to be
412   // adjusted or this should be a data section.
413   LSDASection = Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS,
414                                    ELF::SHF_ALLOC);
415 
416   COFFDebugSymbolsSection = nullptr;
417   COFFDebugTypesSection = nullptr;
418 
419   unsigned DebugSecType = ELF::SHT_PROGBITS;
420 
421   // MIPS .debug_* sections should have SHT_MIPS_DWARF section type
422   // to distinguish among sections contain DWARF and ECOFF debug formats.
423   // Sections with ECOFF debug format are obsoleted and marked by SHT_PROGBITS.
424   if (T.isMIPS())
425     DebugSecType = ELF::SHT_MIPS_DWARF;
426 
427   // Debug Info Sections.
428   DwarfAbbrevSection =
429       Ctx->getELFSection(".debug_abbrev", DebugSecType, 0);
430   DwarfInfoSection = Ctx->getELFSection(".debug_info", DebugSecType, 0);
431   DwarfLineSection = Ctx->getELFSection(".debug_line", DebugSecType, 0);
432   DwarfLineStrSection =
433       Ctx->getELFSection(".debug_line_str", DebugSecType,
434                          ELF::SHF_MERGE | ELF::SHF_STRINGS, 1);
435   DwarfFrameSection = Ctx->getELFSection(".debug_frame", DebugSecType, 0);
436   DwarfPubNamesSection =
437       Ctx->getELFSection(".debug_pubnames", DebugSecType, 0);
438   DwarfPubTypesSection =
439       Ctx->getELFSection(".debug_pubtypes", DebugSecType, 0);
440   DwarfGnuPubNamesSection =
441       Ctx->getELFSection(".debug_gnu_pubnames", DebugSecType, 0);
442   DwarfGnuPubTypesSection =
443       Ctx->getELFSection(".debug_gnu_pubtypes", DebugSecType, 0);
444   DwarfStrSection =
445       Ctx->getELFSection(".debug_str", DebugSecType,
446                          ELF::SHF_MERGE | ELF::SHF_STRINGS, 1);
447   DwarfLocSection = Ctx->getELFSection(".debug_loc", DebugSecType, 0);
448   DwarfARangesSection =
449       Ctx->getELFSection(".debug_aranges", DebugSecType, 0);
450   DwarfRangesSection =
451       Ctx->getELFSection(".debug_ranges", DebugSecType, 0);
452   DwarfMacinfoSection =
453       Ctx->getELFSection(".debug_macinfo", DebugSecType, 0);
454   DwarfMacroSection = Ctx->getELFSection(".debug_macro", DebugSecType, 0);
455 
456   // DWARF5 Experimental Debug Info
457 
458   // Accelerator Tables
459   DwarfDebugNamesSection =
460       Ctx->getELFSection(".debug_names", ELF::SHT_PROGBITS, 0);
461   DwarfAccelNamesSection =
462       Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0);
463   DwarfAccelObjCSection =
464       Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0);
465   DwarfAccelNamespaceSection =
466       Ctx->getELFSection(".apple_namespaces", ELF::SHT_PROGBITS, 0);
467   DwarfAccelTypesSection =
468       Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0);
469 
470   // String Offset and Address Sections
471   DwarfStrOffSection =
472       Ctx->getELFSection(".debug_str_offsets", DebugSecType, 0);
473   DwarfAddrSection = Ctx->getELFSection(".debug_addr", DebugSecType, 0);
474   DwarfRnglistsSection = Ctx->getELFSection(".debug_rnglists", DebugSecType, 0);
475   DwarfLoclistsSection = Ctx->getELFSection(".debug_loclists", DebugSecType, 0);
476 
477   // Fission Sections
478   DwarfInfoDWOSection =
479       Ctx->getELFSection(".debug_info.dwo", DebugSecType, ELF::SHF_EXCLUDE);
480   DwarfTypesDWOSection =
481       Ctx->getELFSection(".debug_types.dwo", DebugSecType, ELF::SHF_EXCLUDE);
482   DwarfAbbrevDWOSection =
483       Ctx->getELFSection(".debug_abbrev.dwo", DebugSecType, ELF::SHF_EXCLUDE);
484   DwarfStrDWOSection = Ctx->getELFSection(
485       ".debug_str.dwo", DebugSecType,
486       ELF::SHF_MERGE | ELF::SHF_STRINGS | ELF::SHF_EXCLUDE, 1);
487   DwarfLineDWOSection =
488       Ctx->getELFSection(".debug_line.dwo", DebugSecType, ELF::SHF_EXCLUDE);
489   DwarfLocDWOSection =
490       Ctx->getELFSection(".debug_loc.dwo", DebugSecType, ELF::SHF_EXCLUDE);
491   DwarfStrOffDWOSection = Ctx->getELFSection(".debug_str_offsets.dwo",
492                                              DebugSecType, ELF::SHF_EXCLUDE);
493   DwarfRnglistsDWOSection =
494       Ctx->getELFSection(".debug_rnglists.dwo", DebugSecType, ELF::SHF_EXCLUDE);
495   DwarfMacinfoDWOSection =
496       Ctx->getELFSection(".debug_macinfo.dwo", DebugSecType, ELF::SHF_EXCLUDE);
497   DwarfMacroDWOSection =
498       Ctx->getELFSection(".debug_macro.dwo", DebugSecType, ELF::SHF_EXCLUDE);
499 
500   DwarfLoclistsDWOSection =
501       Ctx->getELFSection(".debug_loclists.dwo", DebugSecType, ELF::SHF_EXCLUDE);
502 
503   // DWP Sections
504   DwarfCUIndexSection =
505       Ctx->getELFSection(".debug_cu_index", DebugSecType, 0);
506   DwarfTUIndexSection =
507       Ctx->getELFSection(".debug_tu_index", DebugSecType, 0);
508 
509   StackMapSection =
510       Ctx->getELFSection(".llvm_stackmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);
511 
512   FaultMapSection =
513       Ctx->getELFSection(".llvm_faultmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);
514 
515   EHFrameSection =
516       Ctx->getELFSection(".eh_frame", EHSectionType, EHSectionFlags);
517 
518   StackSizesSection = Ctx->getELFSection(".stack_sizes", ELF::SHT_PROGBITS, 0);
519 
520   PseudoProbeSection = Ctx->getELFSection(".pseudo_probe", DebugSecType, 0);
521   PseudoProbeDescSection =
522       Ctx->getELFSection(".pseudo_probe_desc", DebugSecType, 0);
523 }
524 
525 void MCObjectFileInfo::initGOFFMCObjectFileInfo(const Triple &T) {
526   TextSection =
527       Ctx->getGOFFSection(".text", SectionKind::getText(), nullptr, nullptr);
528   BSSSection =
529       Ctx->getGOFFSection(".bss", SectionKind::getBSS(), nullptr, nullptr);
530   PPA1Section =
531       Ctx->getGOFFSection(".ppa1", SectionKind::getMetadata(), TextSection,
532                           MCConstantExpr::create(GOFF::SK_PPA1, *Ctx));
533 }
534 
535 void MCObjectFileInfo::initCOFFMCObjectFileInfo(const Triple &T) {
536   EHFrameSection =
537       Ctx->getCOFFSection(".eh_frame", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
538                                            COFF::IMAGE_SCN_MEM_READ,
539                           SectionKind::getData());
540 
541   // Set the `IMAGE_SCN_MEM_16BIT` flag when compiling for thumb mode.  This is
542   // used to indicate to the linker that the text segment contains thumb instructions
543   // and to set the ISA selection bit for calls accordingly.
544   const bool IsThumb = T.getArch() == Triple::thumb;
545 
546   CommDirectiveSupportsAlignment = true;
547 
548   // COFF
549   BSSSection = Ctx->getCOFFSection(
550       ".bss", COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA |
551                   COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE,
552       SectionKind::getBSS());
553   TextSection = Ctx->getCOFFSection(
554       ".text",
555       (IsThumb ? COFF::IMAGE_SCN_MEM_16BIT : (COFF::SectionCharacteristics)0) |
556           COFF::IMAGE_SCN_CNT_CODE | COFF::IMAGE_SCN_MEM_EXECUTE |
557           COFF::IMAGE_SCN_MEM_READ,
558       SectionKind::getText());
559   DataSection = Ctx->getCOFFSection(
560       ".data", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ |
561                    COFF::IMAGE_SCN_MEM_WRITE,
562       SectionKind::getData());
563   ReadOnlySection = Ctx->getCOFFSection(
564       ".rdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
565       SectionKind::getReadOnly());
566 
567   if (T.getArch() == Triple::x86_64 || T.getArch() == Triple::aarch64 ||
568       T.getArch() == Triple::arm || T.getArch() == Triple::thumb) {
569     // On Windows with SEH, the LSDA is emitted into the .xdata section
570     LSDASection = nullptr;
571   } else {
572     LSDASection = Ctx->getCOFFSection(".gcc_except_table",
573                                       COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
574                                           COFF::IMAGE_SCN_MEM_READ,
575                                       SectionKind::getReadOnly());
576   }
577 
578   // Debug info.
579   COFFDebugSymbolsSection =
580       Ctx->getCOFFSection(".debug$S", (COFF::IMAGE_SCN_MEM_DISCARDABLE |
581                                        COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
582                                        COFF::IMAGE_SCN_MEM_READ),
583                           SectionKind::getMetadata());
584   COFFDebugTypesSection =
585       Ctx->getCOFFSection(".debug$T", (COFF::IMAGE_SCN_MEM_DISCARDABLE |
586                                        COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
587                                        COFF::IMAGE_SCN_MEM_READ),
588                           SectionKind::getMetadata());
589   COFFGlobalTypeHashesSection = Ctx->getCOFFSection(
590       ".debug$H",
591       (COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
592        COFF::IMAGE_SCN_MEM_READ),
593       SectionKind::getMetadata());
594 
595   DwarfAbbrevSection = Ctx->getCOFFSection(
596       ".debug_abbrev",
597       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
598           COFF::IMAGE_SCN_MEM_READ,
599       SectionKind::getMetadata(), "section_abbrev");
600   DwarfInfoSection = Ctx->getCOFFSection(
601       ".debug_info",
602       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
603           COFF::IMAGE_SCN_MEM_READ,
604       SectionKind::getMetadata(), "section_info");
605   DwarfLineSection = Ctx->getCOFFSection(
606       ".debug_line",
607       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
608           COFF::IMAGE_SCN_MEM_READ,
609       SectionKind::getMetadata(), "section_line");
610   DwarfLineStrSection = Ctx->getCOFFSection(
611       ".debug_line_str",
612       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
613           COFF::IMAGE_SCN_MEM_READ,
614       SectionKind::getMetadata(), "section_line_str");
615   DwarfFrameSection = Ctx->getCOFFSection(
616       ".debug_frame",
617       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
618           COFF::IMAGE_SCN_MEM_READ,
619       SectionKind::getMetadata());
620   DwarfPubNamesSection = Ctx->getCOFFSection(
621       ".debug_pubnames",
622       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
623           COFF::IMAGE_SCN_MEM_READ,
624       SectionKind::getMetadata());
625   DwarfPubTypesSection = Ctx->getCOFFSection(
626       ".debug_pubtypes",
627       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
628           COFF::IMAGE_SCN_MEM_READ,
629       SectionKind::getMetadata());
630   DwarfGnuPubNamesSection = Ctx->getCOFFSection(
631       ".debug_gnu_pubnames",
632       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
633           COFF::IMAGE_SCN_MEM_READ,
634       SectionKind::getMetadata());
635   DwarfGnuPubTypesSection = Ctx->getCOFFSection(
636       ".debug_gnu_pubtypes",
637       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
638           COFF::IMAGE_SCN_MEM_READ,
639       SectionKind::getMetadata());
640   DwarfStrSection = Ctx->getCOFFSection(
641       ".debug_str",
642       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
643           COFF::IMAGE_SCN_MEM_READ,
644       SectionKind::getMetadata(), "info_string");
645   DwarfStrOffSection = Ctx->getCOFFSection(
646       ".debug_str_offsets",
647       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
648           COFF::IMAGE_SCN_MEM_READ,
649       SectionKind::getMetadata(), "section_str_off");
650   DwarfLocSection = Ctx->getCOFFSection(
651       ".debug_loc",
652       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
653           COFF::IMAGE_SCN_MEM_READ,
654       SectionKind::getMetadata(), "section_debug_loc");
655   DwarfLoclistsSection = Ctx->getCOFFSection(
656       ".debug_loclists",
657       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
658           COFF::IMAGE_SCN_MEM_READ,
659       SectionKind::getMetadata(), "section_debug_loclists");
660   DwarfARangesSection = Ctx->getCOFFSection(
661       ".debug_aranges",
662       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
663           COFF::IMAGE_SCN_MEM_READ,
664       SectionKind::getMetadata());
665   DwarfRangesSection = Ctx->getCOFFSection(
666       ".debug_ranges",
667       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
668           COFF::IMAGE_SCN_MEM_READ,
669       SectionKind::getMetadata(), "debug_range");
670   DwarfRnglistsSection = Ctx->getCOFFSection(
671       ".debug_rnglists",
672       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
673           COFF::IMAGE_SCN_MEM_READ,
674       SectionKind::getMetadata(), "debug_rnglists");
675   DwarfMacinfoSection = Ctx->getCOFFSection(
676       ".debug_macinfo",
677       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
678           COFF::IMAGE_SCN_MEM_READ,
679       SectionKind::getMetadata(), "debug_macinfo");
680   DwarfMacroSection = Ctx->getCOFFSection(
681       ".debug_macro",
682       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
683           COFF::IMAGE_SCN_MEM_READ,
684       SectionKind::getMetadata(), "debug_macro");
685   DwarfMacinfoDWOSection = Ctx->getCOFFSection(
686       ".debug_macinfo.dwo",
687       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
688           COFF::IMAGE_SCN_MEM_READ,
689       SectionKind::getMetadata(), "debug_macinfo.dwo");
690   DwarfMacroDWOSection = Ctx->getCOFFSection(
691       ".debug_macro.dwo",
692       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
693           COFF::IMAGE_SCN_MEM_READ,
694       SectionKind::getMetadata(), "debug_macro.dwo");
695   DwarfInfoDWOSection = Ctx->getCOFFSection(
696       ".debug_info.dwo",
697       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
698           COFF::IMAGE_SCN_MEM_READ,
699       SectionKind::getMetadata(), "section_info_dwo");
700   DwarfTypesDWOSection = Ctx->getCOFFSection(
701       ".debug_types.dwo",
702       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
703           COFF::IMAGE_SCN_MEM_READ,
704       SectionKind::getMetadata(), "section_types_dwo");
705   DwarfAbbrevDWOSection = Ctx->getCOFFSection(
706       ".debug_abbrev.dwo",
707       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
708           COFF::IMAGE_SCN_MEM_READ,
709       SectionKind::getMetadata(), "section_abbrev_dwo");
710   DwarfStrDWOSection = Ctx->getCOFFSection(
711       ".debug_str.dwo",
712       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
713           COFF::IMAGE_SCN_MEM_READ,
714       SectionKind::getMetadata(), "skel_string");
715   DwarfLineDWOSection = Ctx->getCOFFSection(
716       ".debug_line.dwo",
717       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
718           COFF::IMAGE_SCN_MEM_READ,
719       SectionKind::getMetadata());
720   DwarfLocDWOSection = Ctx->getCOFFSection(
721       ".debug_loc.dwo",
722       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
723           COFF::IMAGE_SCN_MEM_READ,
724       SectionKind::getMetadata(), "skel_loc");
725   DwarfStrOffDWOSection = Ctx->getCOFFSection(
726       ".debug_str_offsets.dwo",
727       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
728           COFF::IMAGE_SCN_MEM_READ,
729       SectionKind::getMetadata(), "section_str_off_dwo");
730   DwarfAddrSection = Ctx->getCOFFSection(
731       ".debug_addr",
732       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
733           COFF::IMAGE_SCN_MEM_READ,
734       SectionKind::getMetadata(), "addr_sec");
735   DwarfCUIndexSection = Ctx->getCOFFSection(
736       ".debug_cu_index",
737       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
738           COFF::IMAGE_SCN_MEM_READ,
739       SectionKind::getMetadata());
740   DwarfTUIndexSection = Ctx->getCOFFSection(
741       ".debug_tu_index",
742       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
743           COFF::IMAGE_SCN_MEM_READ,
744       SectionKind::getMetadata());
745   DwarfDebugNamesSection = Ctx->getCOFFSection(
746       ".debug_names",
747       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
748           COFF::IMAGE_SCN_MEM_READ,
749       SectionKind::getMetadata(), "debug_names_begin");
750   DwarfAccelNamesSection = Ctx->getCOFFSection(
751       ".apple_names",
752       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
753           COFF::IMAGE_SCN_MEM_READ,
754       SectionKind::getMetadata(), "names_begin");
755   DwarfAccelNamespaceSection = Ctx->getCOFFSection(
756       ".apple_namespaces",
757       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
758           COFF::IMAGE_SCN_MEM_READ,
759       SectionKind::getMetadata(), "namespac_begin");
760   DwarfAccelTypesSection = Ctx->getCOFFSection(
761       ".apple_types",
762       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
763           COFF::IMAGE_SCN_MEM_READ,
764       SectionKind::getMetadata(), "types_begin");
765   DwarfAccelObjCSection = Ctx->getCOFFSection(
766       ".apple_objc",
767       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
768           COFF::IMAGE_SCN_MEM_READ,
769       SectionKind::getMetadata(), "objc_begin");
770 
771   DrectveSection = Ctx->getCOFFSection(
772       ".drectve", COFF::IMAGE_SCN_LNK_INFO | COFF::IMAGE_SCN_LNK_REMOVE,
773       SectionKind::getMetadata());
774 
775   PDataSection = Ctx->getCOFFSection(
776       ".pdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
777       SectionKind::getData());
778 
779   XDataSection = Ctx->getCOFFSection(
780       ".xdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
781       SectionKind::getData());
782 
783   SXDataSection = Ctx->getCOFFSection(".sxdata", COFF::IMAGE_SCN_LNK_INFO,
784                                       SectionKind::getMetadata());
785 
786   GEHContSection = Ctx->getCOFFSection(".gehcont$y",
787                                        COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
788                                            COFF::IMAGE_SCN_MEM_READ,
789                                        SectionKind::getMetadata());
790 
791   GFIDsSection = Ctx->getCOFFSection(".gfids$y",
792                                      COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
793                                          COFF::IMAGE_SCN_MEM_READ,
794                                      SectionKind::getMetadata());
795 
796   GIATsSection = Ctx->getCOFFSection(".giats$y",
797                                      COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
798                                          COFF::IMAGE_SCN_MEM_READ,
799                                      SectionKind::getMetadata());
800 
801   GLJMPSection = Ctx->getCOFFSection(".gljmp$y",
802                                      COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
803                                          COFF::IMAGE_SCN_MEM_READ,
804                                      SectionKind::getMetadata());
805 
806   TLSDataSection = Ctx->getCOFFSection(
807       ".tls$", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ |
808                    COFF::IMAGE_SCN_MEM_WRITE,
809       SectionKind::getData());
810 
811   StackMapSection = Ctx->getCOFFSection(".llvm_stackmaps",
812                                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
813                                             COFF::IMAGE_SCN_MEM_READ,
814                                         SectionKind::getReadOnly());
815 }
816 
817 void MCObjectFileInfo::initSPIRVMCObjectFileInfo(const Triple &T) {
818   // Put everything in a single binary section.
819   TextSection = Ctx->getSPIRVSection();
820 }
821 
822 void MCObjectFileInfo::initWasmMCObjectFileInfo(const Triple &T) {
823   TextSection = Ctx->getWasmSection(".text", SectionKind::getText());
824   DataSection = Ctx->getWasmSection(".data", SectionKind::getData());
825 
826   DwarfLineSection =
827       Ctx->getWasmSection(".debug_line", SectionKind::getMetadata());
828   DwarfLineStrSection =
829       Ctx->getWasmSection(".debug_line_str", SectionKind::getMetadata(),
830                           wasm::WASM_SEG_FLAG_STRINGS);
831   DwarfStrSection = Ctx->getWasmSection(
832       ".debug_str", SectionKind::getMetadata(), wasm::WASM_SEG_FLAG_STRINGS);
833   DwarfLocSection =
834       Ctx->getWasmSection(".debug_loc", SectionKind::getMetadata());
835   DwarfAbbrevSection =
836       Ctx->getWasmSection(".debug_abbrev", SectionKind::getMetadata());
837   DwarfARangesSection = Ctx->getWasmSection(".debug_aranges", SectionKind::getMetadata());
838   DwarfRangesSection =
839       Ctx->getWasmSection(".debug_ranges", SectionKind::getMetadata());
840   DwarfMacinfoSection =
841       Ctx->getWasmSection(".debug_macinfo", SectionKind::getMetadata());
842   DwarfMacroSection =
843       Ctx->getWasmSection(".debug_macro", SectionKind::getMetadata());
844   DwarfCUIndexSection = Ctx->getWasmSection(".debug_cu_index", SectionKind::getMetadata());
845   DwarfTUIndexSection = Ctx->getWasmSection(".debug_tu_index", SectionKind::getMetadata());
846   DwarfInfoSection =
847       Ctx->getWasmSection(".debug_info", SectionKind::getMetadata());
848   DwarfFrameSection = Ctx->getWasmSection(".debug_frame", SectionKind::getMetadata());
849   DwarfPubNamesSection = Ctx->getWasmSection(".debug_pubnames", SectionKind::getMetadata());
850   DwarfPubTypesSection = Ctx->getWasmSection(".debug_pubtypes", SectionKind::getMetadata());
851   DwarfGnuPubNamesSection =
852       Ctx->getWasmSection(".debug_gnu_pubnames", SectionKind::getMetadata());
853   DwarfGnuPubTypesSection =
854       Ctx->getWasmSection(".debug_gnu_pubtypes", SectionKind::getMetadata());
855 
856   DwarfDebugNamesSection =
857       Ctx->getWasmSection(".debug_names", SectionKind::getMetadata());
858   DwarfStrOffSection =
859       Ctx->getWasmSection(".debug_str_offsets", SectionKind::getMetadata());
860   DwarfAddrSection =
861       Ctx->getWasmSection(".debug_addr", SectionKind::getMetadata());
862   DwarfRnglistsSection =
863       Ctx->getWasmSection(".debug_rnglists", SectionKind::getMetadata());
864   DwarfLoclistsSection =
865       Ctx->getWasmSection(".debug_loclists", SectionKind::getMetadata());
866 
867   // Fission Sections
868   DwarfInfoDWOSection =
869       Ctx->getWasmSection(".debug_info.dwo", SectionKind::getMetadata());
870   DwarfTypesDWOSection =
871       Ctx->getWasmSection(".debug_types.dwo", SectionKind::getMetadata());
872   DwarfAbbrevDWOSection =
873       Ctx->getWasmSection(".debug_abbrev.dwo", SectionKind::getMetadata());
874   DwarfStrDWOSection =
875       Ctx->getWasmSection(".debug_str.dwo", SectionKind::getMetadata(),
876                           wasm::WASM_SEG_FLAG_STRINGS);
877   DwarfLineDWOSection =
878       Ctx->getWasmSection(".debug_line.dwo", SectionKind::getMetadata());
879   DwarfLocDWOSection =
880       Ctx->getWasmSection(".debug_loc.dwo", SectionKind::getMetadata());
881   DwarfStrOffDWOSection =
882       Ctx->getWasmSection(".debug_str_offsets.dwo", SectionKind::getMetadata());
883   DwarfRnglistsDWOSection =
884       Ctx->getWasmSection(".debug_rnglists.dwo", SectionKind::getMetadata());
885   DwarfMacinfoDWOSection =
886       Ctx->getWasmSection(".debug_macinfo.dwo", SectionKind::getMetadata());
887   DwarfMacroDWOSection =
888       Ctx->getWasmSection(".debug_macro.dwo", SectionKind::getMetadata());
889 
890   DwarfLoclistsDWOSection =
891       Ctx->getWasmSection(".debug_loclists.dwo", SectionKind::getMetadata());
892 
893   // DWP Sections
894   DwarfCUIndexSection =
895       Ctx->getWasmSection(".debug_cu_index", SectionKind::getMetadata());
896   DwarfTUIndexSection =
897       Ctx->getWasmSection(".debug_tu_index", SectionKind::getMetadata());
898 
899   // Wasm use data section for LSDA.
900   // TODO Consider putting each function's exception table in a separate
901   // section, as in -function-sections, to facilitate lld's --gc-section.
902   LSDASection = Ctx->getWasmSection(".rodata.gcc_except_table",
903                                     SectionKind::getReadOnlyWithRel());
904 
905   // TODO: Define more sections.
906 }
907 
908 void MCObjectFileInfo::initXCOFFMCObjectFileInfo(const Triple &T) {
909   // The default csect for program code. Functions without a specified section
910   // get placed into this csect. The choice of csect name is not a property of
911   // the ABI or object file format. For example, the XL compiler uses an unnamed
912   // csect for program code.
913   TextSection = Ctx->getXCOFFSection(
914       ".text", SectionKind::getText(),
915       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_PR, XCOFF::XTY_SD),
916       /* MultiSymbolsAllowed*/ true);
917 
918   DataSection = Ctx->getXCOFFSection(
919       ".data", SectionKind::getData(),
920       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RW, XCOFF::XTY_SD),
921       /* MultiSymbolsAllowed*/ true);
922 
923   ReadOnlySection = Ctx->getXCOFFSection(
924       ".rodata", SectionKind::getReadOnly(),
925       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RO, XCOFF::XTY_SD),
926       /* MultiSymbolsAllowed*/ true);
927   ReadOnlySection->setAlignment(Align(4));
928 
929   ReadOnly8Section = Ctx->getXCOFFSection(
930       ".rodata.8", SectionKind::getReadOnly(),
931       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RO, XCOFF::XTY_SD),
932       /* MultiSymbolsAllowed*/ true);
933   ReadOnly8Section->setAlignment(Align(8));
934 
935   ReadOnly16Section = Ctx->getXCOFFSection(
936       ".rodata.16", SectionKind::getReadOnly(),
937       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RO, XCOFF::XTY_SD),
938       /* MultiSymbolsAllowed*/ true);
939   ReadOnly16Section->setAlignment(Align(16));
940 
941   TLSDataSection = Ctx->getXCOFFSection(
942       ".tdata", SectionKind::getThreadData(),
943       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_TL, XCOFF::XTY_SD),
944       /* MultiSymbolsAllowed*/ true);
945 
946   TOCBaseSection = Ctx->getXCOFFSection(
947       "TOC", SectionKind::getData(),
948       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_TC0,
949                              XCOFF::XTY_SD));
950 
951   // The TOC-base always has 0 size, but 4 byte alignment.
952   TOCBaseSection->setAlignment(Align(4));
953 
954   LSDASection = Ctx->getXCOFFSection(
955       ".gcc_except_table", SectionKind::getReadOnly(),
956       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RO,
957                              XCOFF::XTY_SD));
958 
959   CompactUnwindSection = Ctx->getXCOFFSection(
960       ".eh_info_table", SectionKind::getData(),
961       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RW,
962                              XCOFF::XTY_SD));
963 
964   // DWARF sections for XCOFF are not csects. They are special STYP_DWARF
965   // sections, and the individual DWARF sections are distinguished by their
966   // section subtype.
967   DwarfAbbrevSection = Ctx->getXCOFFSection(
968       ".dwabrev", SectionKind::getMetadata(), /* CsectProperties */ None,
969       /* MultiSymbolsAllowed */ true, ".dwabrev", XCOFF::SSUBTYP_DWABREV);
970 
971   DwarfInfoSection = Ctx->getXCOFFSection(
972       ".dwinfo", SectionKind::getMetadata(), /* CsectProperties */ None,
973       /* MultiSymbolsAllowed */ true, ".dwinfo", XCOFF::SSUBTYP_DWINFO);
974 
975   DwarfLineSection = Ctx->getXCOFFSection(
976       ".dwline", SectionKind::getMetadata(), /* CsectProperties */ None,
977       /* MultiSymbolsAllowed */ true, ".dwline", XCOFF::SSUBTYP_DWLINE);
978 
979   DwarfFrameSection = Ctx->getXCOFFSection(
980       ".dwframe", SectionKind::getMetadata(), /* CsectProperties */ None,
981       /* MultiSymbolsAllowed */ true, ".dwframe", XCOFF::SSUBTYP_DWFRAME);
982 
983   DwarfPubNamesSection = Ctx->getXCOFFSection(
984       ".dwpbnms", SectionKind::getMetadata(), /* CsectProperties */ None,
985       /* MultiSymbolsAllowed */ true, ".dwpbnms", XCOFF::SSUBTYP_DWPBNMS);
986 
987   DwarfPubTypesSection = Ctx->getXCOFFSection(
988       ".dwpbtyp", SectionKind::getMetadata(), /* CsectProperties */ None,
989       /* MultiSymbolsAllowed */ true, ".dwpbtyp", XCOFF::SSUBTYP_DWPBTYP);
990 
991   DwarfStrSection = Ctx->getXCOFFSection(
992       ".dwstr", SectionKind::getMetadata(), /* CsectProperties */ None,
993       /* MultiSymbolsAllowed */ true, ".dwstr", XCOFF::SSUBTYP_DWSTR);
994 
995   DwarfLocSection = Ctx->getXCOFFSection(
996       ".dwloc", SectionKind::getMetadata(), /* CsectProperties */ None,
997       /* MultiSymbolsAllowed */ true, ".dwloc", XCOFF::SSUBTYP_DWLOC);
998 
999   DwarfARangesSection = Ctx->getXCOFFSection(
1000       ".dwarnge", SectionKind::getMetadata(), /* CsectProperties */ None,
1001       /* MultiSymbolsAllowed */ true, ".dwarnge", XCOFF::SSUBTYP_DWARNGE);
1002 
1003   DwarfRangesSection = Ctx->getXCOFFSection(
1004       ".dwrnges", SectionKind::getMetadata(), /* CsectProperties */ None,
1005       /* MultiSymbolsAllowed */ true, ".dwrnges", XCOFF::SSUBTYP_DWRNGES);
1006 
1007   DwarfMacinfoSection = Ctx->getXCOFFSection(
1008       ".dwmac", SectionKind::getMetadata(), /* CsectProperties */ None,
1009       /* MultiSymbolsAllowed */ true, ".dwmac", XCOFF::SSUBTYP_DWMAC);
1010 }
1011 
1012 MCObjectFileInfo::~MCObjectFileInfo() = default;
1013 
1014 void MCObjectFileInfo::initMCObjectFileInfo(MCContext &MCCtx, bool PIC,
1015                                             bool LargeCodeModel) {
1016   PositionIndependent = PIC;
1017   Ctx = &MCCtx;
1018 
1019   // Common.
1020   CommDirectiveSupportsAlignment = true;
1021   SupportsWeakOmittedEHFrame = true;
1022   SupportsCompactUnwindWithoutEHFrame = false;
1023   OmitDwarfIfHaveCompactUnwind = false;
1024 
1025   FDECFIEncoding = dwarf::DW_EH_PE_absptr;
1026 
1027   CompactUnwindDwarfEHFrameOnly = 0;
1028 
1029   EHFrameSection = nullptr;             // Created on demand.
1030   CompactUnwindSection = nullptr;       // Used only by selected targets.
1031   DwarfAccelNamesSection = nullptr;     // Used only by selected targets.
1032   DwarfAccelObjCSection = nullptr;      // Used only by selected targets.
1033   DwarfAccelNamespaceSection = nullptr; // Used only by selected targets.
1034   DwarfAccelTypesSection = nullptr;     // Used only by selected targets.
1035 
1036   Triple TheTriple = Ctx->getTargetTriple();
1037   switch (Ctx->getObjectFileType()) {
1038   case MCContext::IsMachO:
1039     initMachOMCObjectFileInfo(TheTriple);
1040     break;
1041   case MCContext::IsCOFF:
1042     initCOFFMCObjectFileInfo(TheTriple);
1043     break;
1044   case MCContext::IsELF:
1045     initELFMCObjectFileInfo(TheTriple, LargeCodeModel);
1046     break;
1047   case MCContext::IsGOFF:
1048     initGOFFMCObjectFileInfo(TheTriple);
1049     break;
1050   case MCContext::IsSPIRV:
1051     initSPIRVMCObjectFileInfo(TheTriple);
1052     break;
1053   case MCContext::IsWasm:
1054     initWasmMCObjectFileInfo(TheTriple);
1055     break;
1056   case MCContext::IsXCOFF:
1057     initXCOFFMCObjectFileInfo(TheTriple);
1058     break;
1059   case MCContext::IsDXContainer:
1060     break;
1061   }
1062 }
1063 
1064 MCSection *MCObjectFileInfo::getDwarfComdatSection(const char *Name,
1065                                                    uint64_t Hash) const {
1066   switch (Ctx->getTargetTriple().getObjectFormat()) {
1067   case Triple::ELF:
1068     return Ctx->getELFSection(Name, ELF::SHT_PROGBITS, ELF::SHF_GROUP, 0,
1069                               utostr(Hash), /*IsComdat=*/true);
1070   case Triple::Wasm:
1071     return Ctx->getWasmSection(Name, SectionKind::getMetadata(), 0,
1072                                utostr(Hash), MCContext::GenericSectionID);
1073   case Triple::MachO:
1074   case Triple::COFF:
1075   case Triple::GOFF:
1076   case Triple::SPIRV:
1077   case Triple::XCOFF:
1078   case Triple::DXContainer:
1079   case Triple::UnknownObjectFormat:
1080     report_fatal_error("Cannot get DWARF comdat section for this object file "
1081                        "format: not implemented.");
1082     break;
1083   }
1084   llvm_unreachable("Unknown ObjectFormatType");
1085 }
1086 
1087 MCSection *
1088 MCObjectFileInfo::getStackSizesSection(const MCSection &TextSec) const {
1089   if (Ctx->getObjectFileType() != MCContext::IsELF)
1090     return StackSizesSection;
1091 
1092   const MCSectionELF &ElfSec = static_cast<const MCSectionELF &>(TextSec);
1093   unsigned Flags = ELF::SHF_LINK_ORDER;
1094   StringRef GroupName;
1095   if (const MCSymbol *Group = ElfSec.getGroup()) {
1096     GroupName = Group->getName();
1097     Flags |= ELF::SHF_GROUP;
1098   }
1099 
1100   return Ctx->getELFSection(".stack_sizes", ELF::SHT_PROGBITS, Flags, 0,
1101                             GroupName, true, ElfSec.getUniqueID(),
1102                             cast<MCSymbolELF>(TextSec.getBeginSymbol()));
1103 }
1104 
1105 MCSection *
1106 MCObjectFileInfo::getBBAddrMapSection(const MCSection &TextSec) const {
1107   if (Ctx->getObjectFileType() != MCContext::IsELF)
1108     return nullptr;
1109 
1110   const MCSectionELF &ElfSec = static_cast<const MCSectionELF &>(TextSec);
1111   unsigned Flags = ELF::SHF_LINK_ORDER;
1112   StringRef GroupName;
1113   if (const MCSymbol *Group = ElfSec.getGroup()) {
1114     GroupName = Group->getName();
1115     Flags |= ELF::SHF_GROUP;
1116   }
1117 
1118   // Use the text section's begin symbol and unique ID to create a separate
1119   // .llvm_bb_addr_map section associated with every unique text section.
1120   return Ctx->getELFSection(".llvm_bb_addr_map", ELF::SHT_LLVM_BB_ADDR_MAP,
1121                             Flags, 0, GroupName, true, ElfSec.getUniqueID(),
1122                             cast<MCSymbolELF>(TextSec.getBeginSymbol()));
1123 }
1124 
1125 MCSection *
1126 MCObjectFileInfo::getPseudoProbeSection(const MCSection *TextSec) const {
1127   if (Ctx->getObjectFileType() == MCContext::IsELF) {
1128     const auto *ElfSec = static_cast<const MCSectionELF *>(TextSec);
1129     // Create a separate section for probes that comes with a comdat function.
1130     if (const MCSymbol *Group = ElfSec->getGroup()) {
1131       auto *S = static_cast<MCSectionELF *>(PseudoProbeSection);
1132       auto Flags = S->getFlags() | ELF::SHF_GROUP;
1133       return Ctx->getELFSection(S->getName(), S->getType(), Flags,
1134                                 S->getEntrySize(), Group->getName(),
1135                                 /*IsComdat=*/true);
1136     }
1137   }
1138   return PseudoProbeSection;
1139 }
1140 
1141 MCSection *
1142 MCObjectFileInfo::getPseudoProbeDescSection(StringRef FuncName) const {
1143   if (Ctx->getObjectFileType() == MCContext::IsELF) {
1144     // Create a separate comdat group for each function's descriptor in order
1145     // for the linker to deduplicate. The duplication, must be from different
1146     // tranlation unit, can come from:
1147     //  1. Inline functions defined in header files;
1148     //  2. ThinLTO imported funcions;
1149     //  3. Weak-linkage definitions.
1150     // Use a concatenation of the section name and the function name as the
1151     // group name so that descriptor-only groups won't be folded with groups of
1152     // code.
1153     if (Ctx->getTargetTriple().supportsCOMDAT() && !FuncName.empty()) {
1154       auto *S = static_cast<MCSectionELF *>(PseudoProbeDescSection);
1155       auto Flags = S->getFlags() | ELF::SHF_GROUP;
1156       return Ctx->getELFSection(S->getName(), S->getType(), Flags,
1157                                 S->getEntrySize(),
1158                                 S->getName() + "_" + FuncName,
1159                                 /*IsComdat=*/true);
1160     }
1161   }
1162   return PseudoProbeDescSection;
1163 }
1164