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     // On Windows 64 with SEH, the LSDA is emitted into the .xdata section
569     LSDASection = nullptr;
570   } else {
571     LSDASection = Ctx->getCOFFSection(".gcc_except_table",
572                                       COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
573                                           COFF::IMAGE_SCN_MEM_READ,
574                                       SectionKind::getReadOnly());
575   }
576 
577   // Debug info.
578   COFFDebugSymbolsSection =
579       Ctx->getCOFFSection(".debug$S", (COFF::IMAGE_SCN_MEM_DISCARDABLE |
580                                        COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
581                                        COFF::IMAGE_SCN_MEM_READ),
582                           SectionKind::getMetadata());
583   COFFDebugTypesSection =
584       Ctx->getCOFFSection(".debug$T", (COFF::IMAGE_SCN_MEM_DISCARDABLE |
585                                        COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
586                                        COFF::IMAGE_SCN_MEM_READ),
587                           SectionKind::getMetadata());
588   COFFGlobalTypeHashesSection = Ctx->getCOFFSection(
589       ".debug$H",
590       (COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
591        COFF::IMAGE_SCN_MEM_READ),
592       SectionKind::getMetadata());
593 
594   DwarfAbbrevSection = Ctx->getCOFFSection(
595       ".debug_abbrev",
596       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
597           COFF::IMAGE_SCN_MEM_READ,
598       SectionKind::getMetadata(), "section_abbrev");
599   DwarfInfoSection = Ctx->getCOFFSection(
600       ".debug_info",
601       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
602           COFF::IMAGE_SCN_MEM_READ,
603       SectionKind::getMetadata(), "section_info");
604   DwarfLineSection = Ctx->getCOFFSection(
605       ".debug_line",
606       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
607           COFF::IMAGE_SCN_MEM_READ,
608       SectionKind::getMetadata(), "section_line");
609   DwarfLineStrSection = Ctx->getCOFFSection(
610       ".debug_line_str",
611       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
612           COFF::IMAGE_SCN_MEM_READ,
613       SectionKind::getMetadata(), "section_line_str");
614   DwarfFrameSection = Ctx->getCOFFSection(
615       ".debug_frame",
616       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
617           COFF::IMAGE_SCN_MEM_READ,
618       SectionKind::getMetadata());
619   DwarfPubNamesSection = Ctx->getCOFFSection(
620       ".debug_pubnames",
621       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
622           COFF::IMAGE_SCN_MEM_READ,
623       SectionKind::getMetadata());
624   DwarfPubTypesSection = Ctx->getCOFFSection(
625       ".debug_pubtypes",
626       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
627           COFF::IMAGE_SCN_MEM_READ,
628       SectionKind::getMetadata());
629   DwarfGnuPubNamesSection = Ctx->getCOFFSection(
630       ".debug_gnu_pubnames",
631       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
632           COFF::IMAGE_SCN_MEM_READ,
633       SectionKind::getMetadata());
634   DwarfGnuPubTypesSection = Ctx->getCOFFSection(
635       ".debug_gnu_pubtypes",
636       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
637           COFF::IMAGE_SCN_MEM_READ,
638       SectionKind::getMetadata());
639   DwarfStrSection = Ctx->getCOFFSection(
640       ".debug_str",
641       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
642           COFF::IMAGE_SCN_MEM_READ,
643       SectionKind::getMetadata(), "info_string");
644   DwarfStrOffSection = Ctx->getCOFFSection(
645       ".debug_str_offsets",
646       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
647           COFF::IMAGE_SCN_MEM_READ,
648       SectionKind::getMetadata(), "section_str_off");
649   DwarfLocSection = Ctx->getCOFFSection(
650       ".debug_loc",
651       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
652           COFF::IMAGE_SCN_MEM_READ,
653       SectionKind::getMetadata(), "section_debug_loc");
654   DwarfLoclistsSection = Ctx->getCOFFSection(
655       ".debug_loclists",
656       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
657           COFF::IMAGE_SCN_MEM_READ,
658       SectionKind::getMetadata(), "section_debug_loclists");
659   DwarfARangesSection = Ctx->getCOFFSection(
660       ".debug_aranges",
661       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
662           COFF::IMAGE_SCN_MEM_READ,
663       SectionKind::getMetadata());
664   DwarfRangesSection = Ctx->getCOFFSection(
665       ".debug_ranges",
666       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
667           COFF::IMAGE_SCN_MEM_READ,
668       SectionKind::getMetadata(), "debug_range");
669   DwarfRnglistsSection = Ctx->getCOFFSection(
670       ".debug_rnglists",
671       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
672           COFF::IMAGE_SCN_MEM_READ,
673       SectionKind::getMetadata(), "debug_rnglists");
674   DwarfMacinfoSection = Ctx->getCOFFSection(
675       ".debug_macinfo",
676       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
677           COFF::IMAGE_SCN_MEM_READ,
678       SectionKind::getMetadata(), "debug_macinfo");
679   DwarfMacroSection = Ctx->getCOFFSection(
680       ".debug_macro",
681       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
682           COFF::IMAGE_SCN_MEM_READ,
683       SectionKind::getMetadata(), "debug_macro");
684   DwarfMacinfoDWOSection = Ctx->getCOFFSection(
685       ".debug_macinfo.dwo",
686       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
687           COFF::IMAGE_SCN_MEM_READ,
688       SectionKind::getMetadata(), "debug_macinfo.dwo");
689   DwarfMacroDWOSection = Ctx->getCOFFSection(
690       ".debug_macro.dwo",
691       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
692           COFF::IMAGE_SCN_MEM_READ,
693       SectionKind::getMetadata(), "debug_macro.dwo");
694   DwarfInfoDWOSection = Ctx->getCOFFSection(
695       ".debug_info.dwo",
696       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
697           COFF::IMAGE_SCN_MEM_READ,
698       SectionKind::getMetadata(), "section_info_dwo");
699   DwarfTypesDWOSection = Ctx->getCOFFSection(
700       ".debug_types.dwo",
701       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
702           COFF::IMAGE_SCN_MEM_READ,
703       SectionKind::getMetadata(), "section_types_dwo");
704   DwarfAbbrevDWOSection = Ctx->getCOFFSection(
705       ".debug_abbrev.dwo",
706       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
707           COFF::IMAGE_SCN_MEM_READ,
708       SectionKind::getMetadata(), "section_abbrev_dwo");
709   DwarfStrDWOSection = Ctx->getCOFFSection(
710       ".debug_str.dwo",
711       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
712           COFF::IMAGE_SCN_MEM_READ,
713       SectionKind::getMetadata(), "skel_string");
714   DwarfLineDWOSection = Ctx->getCOFFSection(
715       ".debug_line.dwo",
716       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
717           COFF::IMAGE_SCN_MEM_READ,
718       SectionKind::getMetadata());
719   DwarfLocDWOSection = Ctx->getCOFFSection(
720       ".debug_loc.dwo",
721       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
722           COFF::IMAGE_SCN_MEM_READ,
723       SectionKind::getMetadata(), "skel_loc");
724   DwarfStrOffDWOSection = Ctx->getCOFFSection(
725       ".debug_str_offsets.dwo",
726       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
727           COFF::IMAGE_SCN_MEM_READ,
728       SectionKind::getMetadata(), "section_str_off_dwo");
729   DwarfAddrSection = Ctx->getCOFFSection(
730       ".debug_addr",
731       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
732           COFF::IMAGE_SCN_MEM_READ,
733       SectionKind::getMetadata(), "addr_sec");
734   DwarfCUIndexSection = Ctx->getCOFFSection(
735       ".debug_cu_index",
736       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
737           COFF::IMAGE_SCN_MEM_READ,
738       SectionKind::getMetadata());
739   DwarfTUIndexSection = Ctx->getCOFFSection(
740       ".debug_tu_index",
741       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
742           COFF::IMAGE_SCN_MEM_READ,
743       SectionKind::getMetadata());
744   DwarfDebugNamesSection = Ctx->getCOFFSection(
745       ".debug_names",
746       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
747           COFF::IMAGE_SCN_MEM_READ,
748       SectionKind::getMetadata(), "debug_names_begin");
749   DwarfAccelNamesSection = Ctx->getCOFFSection(
750       ".apple_names",
751       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
752           COFF::IMAGE_SCN_MEM_READ,
753       SectionKind::getMetadata(), "names_begin");
754   DwarfAccelNamespaceSection = Ctx->getCOFFSection(
755       ".apple_namespaces",
756       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
757           COFF::IMAGE_SCN_MEM_READ,
758       SectionKind::getMetadata(), "namespac_begin");
759   DwarfAccelTypesSection = Ctx->getCOFFSection(
760       ".apple_types",
761       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
762           COFF::IMAGE_SCN_MEM_READ,
763       SectionKind::getMetadata(), "types_begin");
764   DwarfAccelObjCSection = Ctx->getCOFFSection(
765       ".apple_objc",
766       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
767           COFF::IMAGE_SCN_MEM_READ,
768       SectionKind::getMetadata(), "objc_begin");
769 
770   DrectveSection = Ctx->getCOFFSection(
771       ".drectve", COFF::IMAGE_SCN_LNK_INFO | COFF::IMAGE_SCN_LNK_REMOVE,
772       SectionKind::getMetadata());
773 
774   PDataSection = Ctx->getCOFFSection(
775       ".pdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
776       SectionKind::getData());
777 
778   XDataSection = Ctx->getCOFFSection(
779       ".xdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
780       SectionKind::getData());
781 
782   SXDataSection = Ctx->getCOFFSection(".sxdata", COFF::IMAGE_SCN_LNK_INFO,
783                                       SectionKind::getMetadata());
784 
785   GEHContSection = Ctx->getCOFFSection(".gehcont$y",
786                                        COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
787                                            COFF::IMAGE_SCN_MEM_READ,
788                                        SectionKind::getMetadata());
789 
790   GFIDsSection = Ctx->getCOFFSection(".gfids$y",
791                                      COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
792                                          COFF::IMAGE_SCN_MEM_READ,
793                                      SectionKind::getMetadata());
794 
795   GIATsSection = Ctx->getCOFFSection(".giats$y",
796                                      COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
797                                          COFF::IMAGE_SCN_MEM_READ,
798                                      SectionKind::getMetadata());
799 
800   GLJMPSection = Ctx->getCOFFSection(".gljmp$y",
801                                      COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
802                                          COFF::IMAGE_SCN_MEM_READ,
803                                      SectionKind::getMetadata());
804 
805   TLSDataSection = Ctx->getCOFFSection(
806       ".tls$", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ |
807                    COFF::IMAGE_SCN_MEM_WRITE,
808       SectionKind::getData());
809 
810   StackMapSection = Ctx->getCOFFSection(".llvm_stackmaps",
811                                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
812                                             COFF::IMAGE_SCN_MEM_READ,
813                                         SectionKind::getReadOnly());
814 }
815 
816 void MCObjectFileInfo::initSPIRVMCObjectFileInfo(const Triple &T) {
817   // Put everything in a single binary section.
818   TextSection = Ctx->getSPIRVSection();
819 }
820 
821 void MCObjectFileInfo::initWasmMCObjectFileInfo(const Triple &T) {
822   TextSection = Ctx->getWasmSection(".text", SectionKind::getText());
823   DataSection = Ctx->getWasmSection(".data", SectionKind::getData());
824 
825   DwarfLineSection =
826       Ctx->getWasmSection(".debug_line", SectionKind::getMetadata());
827   DwarfLineStrSection =
828       Ctx->getWasmSection(".debug_line_str", SectionKind::getMetadata(),
829                           wasm::WASM_SEG_FLAG_STRINGS);
830   DwarfStrSection = Ctx->getWasmSection(
831       ".debug_str", SectionKind::getMetadata(), wasm::WASM_SEG_FLAG_STRINGS);
832   DwarfLocSection =
833       Ctx->getWasmSection(".debug_loc", SectionKind::getMetadata());
834   DwarfAbbrevSection =
835       Ctx->getWasmSection(".debug_abbrev", SectionKind::getMetadata());
836   DwarfARangesSection = Ctx->getWasmSection(".debug_aranges", SectionKind::getMetadata());
837   DwarfRangesSection =
838       Ctx->getWasmSection(".debug_ranges", SectionKind::getMetadata());
839   DwarfMacinfoSection =
840       Ctx->getWasmSection(".debug_macinfo", SectionKind::getMetadata());
841   DwarfMacroSection =
842       Ctx->getWasmSection(".debug_macro", SectionKind::getMetadata());
843   DwarfCUIndexSection = Ctx->getWasmSection(".debug_cu_index", SectionKind::getMetadata());
844   DwarfTUIndexSection = Ctx->getWasmSection(".debug_tu_index", SectionKind::getMetadata());
845   DwarfInfoSection =
846       Ctx->getWasmSection(".debug_info", SectionKind::getMetadata());
847   DwarfFrameSection = Ctx->getWasmSection(".debug_frame", SectionKind::getMetadata());
848   DwarfPubNamesSection = Ctx->getWasmSection(".debug_pubnames", SectionKind::getMetadata());
849   DwarfPubTypesSection = Ctx->getWasmSection(".debug_pubtypes", SectionKind::getMetadata());
850   DwarfGnuPubNamesSection =
851       Ctx->getWasmSection(".debug_gnu_pubnames", SectionKind::getMetadata());
852   DwarfGnuPubTypesSection =
853       Ctx->getWasmSection(".debug_gnu_pubtypes", SectionKind::getMetadata());
854 
855   DwarfDebugNamesSection =
856       Ctx->getWasmSection(".debug_names", SectionKind::getMetadata());
857   DwarfStrOffSection =
858       Ctx->getWasmSection(".debug_str_offsets", SectionKind::getMetadata());
859   DwarfAddrSection =
860       Ctx->getWasmSection(".debug_addr", SectionKind::getMetadata());
861   DwarfRnglistsSection =
862       Ctx->getWasmSection(".debug_rnglists", SectionKind::getMetadata());
863   DwarfLoclistsSection =
864       Ctx->getWasmSection(".debug_loclists", SectionKind::getMetadata());
865 
866   // Fission Sections
867   DwarfInfoDWOSection =
868       Ctx->getWasmSection(".debug_info.dwo", SectionKind::getMetadata());
869   DwarfTypesDWOSection =
870       Ctx->getWasmSection(".debug_types.dwo", SectionKind::getMetadata());
871   DwarfAbbrevDWOSection =
872       Ctx->getWasmSection(".debug_abbrev.dwo", SectionKind::getMetadata());
873   DwarfStrDWOSection =
874       Ctx->getWasmSection(".debug_str.dwo", SectionKind::getMetadata(),
875                           wasm::WASM_SEG_FLAG_STRINGS);
876   DwarfLineDWOSection =
877       Ctx->getWasmSection(".debug_line.dwo", SectionKind::getMetadata());
878   DwarfLocDWOSection =
879       Ctx->getWasmSection(".debug_loc.dwo", SectionKind::getMetadata());
880   DwarfStrOffDWOSection =
881       Ctx->getWasmSection(".debug_str_offsets.dwo", SectionKind::getMetadata());
882   DwarfRnglistsDWOSection =
883       Ctx->getWasmSection(".debug_rnglists.dwo", SectionKind::getMetadata());
884   DwarfMacinfoDWOSection =
885       Ctx->getWasmSection(".debug_macinfo.dwo", SectionKind::getMetadata());
886   DwarfMacroDWOSection =
887       Ctx->getWasmSection(".debug_macro.dwo", SectionKind::getMetadata());
888 
889   DwarfLoclistsDWOSection =
890       Ctx->getWasmSection(".debug_loclists.dwo", SectionKind::getMetadata());
891 
892   // DWP Sections
893   DwarfCUIndexSection =
894       Ctx->getWasmSection(".debug_cu_index", SectionKind::getMetadata());
895   DwarfTUIndexSection =
896       Ctx->getWasmSection(".debug_tu_index", SectionKind::getMetadata());
897 
898   // Wasm use data section for LSDA.
899   // TODO Consider putting each function's exception table in a separate
900   // section, as in -function-sections, to facilitate lld's --gc-section.
901   LSDASection = Ctx->getWasmSection(".rodata.gcc_except_table",
902                                     SectionKind::getReadOnlyWithRel());
903 
904   // TODO: Define more sections.
905 }
906 
907 void MCObjectFileInfo::initXCOFFMCObjectFileInfo(const Triple &T) {
908   // The default csect for program code. Functions without a specified section
909   // get placed into this csect. The choice of csect name is not a property of
910   // the ABI or object file format. For example, the XL compiler uses an unnamed
911   // csect for program code.
912   TextSection = Ctx->getXCOFFSection(
913       ".text", SectionKind::getText(),
914       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_PR, XCOFF::XTY_SD),
915       /* MultiSymbolsAllowed*/ true);
916 
917   DataSection = Ctx->getXCOFFSection(
918       ".data", SectionKind::getData(),
919       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RW, XCOFF::XTY_SD),
920       /* MultiSymbolsAllowed*/ true);
921 
922   ReadOnlySection = Ctx->getXCOFFSection(
923       ".rodata", SectionKind::getReadOnly(),
924       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RO, XCOFF::XTY_SD),
925       /* MultiSymbolsAllowed*/ true);
926   ReadOnlySection->setAlignment(Align(4));
927 
928   ReadOnly8Section = Ctx->getXCOFFSection(
929       ".rodata.8", SectionKind::getReadOnly(),
930       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RO, XCOFF::XTY_SD),
931       /* MultiSymbolsAllowed*/ true);
932   ReadOnly8Section->setAlignment(Align(8));
933 
934   ReadOnly16Section = Ctx->getXCOFFSection(
935       ".rodata.16", SectionKind::getReadOnly(),
936       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RO, XCOFF::XTY_SD),
937       /* MultiSymbolsAllowed*/ true);
938   ReadOnly16Section->setAlignment(Align(16));
939 
940   TLSDataSection = Ctx->getXCOFFSection(
941       ".tdata", SectionKind::getThreadData(),
942       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_TL, XCOFF::XTY_SD),
943       /* MultiSymbolsAllowed*/ true);
944 
945   TOCBaseSection = Ctx->getXCOFFSection(
946       "TOC", SectionKind::getData(),
947       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_TC0,
948                              XCOFF::XTY_SD));
949 
950   // The TOC-base always has 0 size, but 4 byte alignment.
951   TOCBaseSection->setAlignment(Align(4));
952 
953   LSDASection = Ctx->getXCOFFSection(
954       ".gcc_except_table", SectionKind::getReadOnly(),
955       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RO,
956                              XCOFF::XTY_SD));
957 
958   CompactUnwindSection = Ctx->getXCOFFSection(
959       ".eh_info_table", SectionKind::getData(),
960       XCOFF::CsectProperties(XCOFF::StorageMappingClass::XMC_RW,
961                              XCOFF::XTY_SD));
962 
963   // DWARF sections for XCOFF are not csects. They are special STYP_DWARF
964   // sections, and the individual DWARF sections are distinguished by their
965   // section subtype.
966   DwarfAbbrevSection = Ctx->getXCOFFSection(
967       ".dwabrev", SectionKind::getMetadata(), /* CsectProperties */ None,
968       /* MultiSymbolsAllowed */ true, ".dwabrev", XCOFF::SSUBTYP_DWABREV);
969 
970   DwarfInfoSection = Ctx->getXCOFFSection(
971       ".dwinfo", SectionKind::getMetadata(), /* CsectProperties */ None,
972       /* MultiSymbolsAllowed */ true, ".dwinfo", XCOFF::SSUBTYP_DWINFO);
973 
974   DwarfLineSection = Ctx->getXCOFFSection(
975       ".dwline", SectionKind::getMetadata(), /* CsectProperties */ None,
976       /* MultiSymbolsAllowed */ true, ".dwline", XCOFF::SSUBTYP_DWLINE);
977 
978   DwarfFrameSection = Ctx->getXCOFFSection(
979       ".dwframe", SectionKind::getMetadata(), /* CsectProperties */ None,
980       /* MultiSymbolsAllowed */ true, ".dwframe", XCOFF::SSUBTYP_DWFRAME);
981 
982   DwarfPubNamesSection = Ctx->getXCOFFSection(
983       ".dwpbnms", SectionKind::getMetadata(), /* CsectProperties */ None,
984       /* MultiSymbolsAllowed */ true, ".dwpbnms", XCOFF::SSUBTYP_DWPBNMS);
985 
986   DwarfPubTypesSection = Ctx->getXCOFFSection(
987       ".dwpbtyp", SectionKind::getMetadata(), /* CsectProperties */ None,
988       /* MultiSymbolsAllowed */ true, ".dwpbtyp", XCOFF::SSUBTYP_DWPBTYP);
989 
990   DwarfStrSection = Ctx->getXCOFFSection(
991       ".dwstr", SectionKind::getMetadata(), /* CsectProperties */ None,
992       /* MultiSymbolsAllowed */ true, ".dwstr", XCOFF::SSUBTYP_DWSTR);
993 
994   DwarfLocSection = Ctx->getXCOFFSection(
995       ".dwloc", SectionKind::getMetadata(), /* CsectProperties */ None,
996       /* MultiSymbolsAllowed */ true, ".dwloc", XCOFF::SSUBTYP_DWLOC);
997 
998   DwarfARangesSection = Ctx->getXCOFFSection(
999       ".dwarnge", SectionKind::getMetadata(), /* CsectProperties */ None,
1000       /* MultiSymbolsAllowed */ true, ".dwarnge", XCOFF::SSUBTYP_DWARNGE);
1001 
1002   DwarfRangesSection = Ctx->getXCOFFSection(
1003       ".dwrnges", SectionKind::getMetadata(), /* CsectProperties */ None,
1004       /* MultiSymbolsAllowed */ true, ".dwrnges", XCOFF::SSUBTYP_DWRNGES);
1005 
1006   DwarfMacinfoSection = Ctx->getXCOFFSection(
1007       ".dwmac", SectionKind::getMetadata(), /* CsectProperties */ None,
1008       /* MultiSymbolsAllowed */ true, ".dwmac", XCOFF::SSUBTYP_DWMAC);
1009 }
1010 
1011 MCObjectFileInfo::~MCObjectFileInfo() = default;
1012 
1013 void MCObjectFileInfo::initMCObjectFileInfo(MCContext &MCCtx, bool PIC,
1014                                             bool LargeCodeModel) {
1015   PositionIndependent = PIC;
1016   Ctx = &MCCtx;
1017 
1018   // Common.
1019   CommDirectiveSupportsAlignment = true;
1020   SupportsWeakOmittedEHFrame = true;
1021   SupportsCompactUnwindWithoutEHFrame = false;
1022   OmitDwarfIfHaveCompactUnwind = false;
1023 
1024   FDECFIEncoding = dwarf::DW_EH_PE_absptr;
1025 
1026   CompactUnwindDwarfEHFrameOnly = 0;
1027 
1028   EHFrameSection = nullptr;             // Created on demand.
1029   CompactUnwindSection = nullptr;       // Used only by selected targets.
1030   DwarfAccelNamesSection = nullptr;     // Used only by selected targets.
1031   DwarfAccelObjCSection = nullptr;      // Used only by selected targets.
1032   DwarfAccelNamespaceSection = nullptr; // Used only by selected targets.
1033   DwarfAccelTypesSection = nullptr;     // Used only by selected targets.
1034 
1035   Triple TheTriple = Ctx->getTargetTriple();
1036   switch (Ctx->getObjectFileType()) {
1037   case MCContext::IsMachO:
1038     initMachOMCObjectFileInfo(TheTriple);
1039     break;
1040   case MCContext::IsCOFF:
1041     initCOFFMCObjectFileInfo(TheTriple);
1042     break;
1043   case MCContext::IsELF:
1044     initELFMCObjectFileInfo(TheTriple, LargeCodeModel);
1045     break;
1046   case MCContext::IsGOFF:
1047     initGOFFMCObjectFileInfo(TheTriple);
1048     break;
1049   case MCContext::IsSPIRV:
1050     initSPIRVMCObjectFileInfo(TheTriple);
1051     break;
1052   case MCContext::IsWasm:
1053     initWasmMCObjectFileInfo(TheTriple);
1054     break;
1055   case MCContext::IsXCOFF:
1056     initXCOFFMCObjectFileInfo(TheTriple);
1057     break;
1058   case MCContext::IsDXContainer:
1059     break;
1060   }
1061 }
1062 
1063 MCSection *MCObjectFileInfo::getDwarfComdatSection(const char *Name,
1064                                                    uint64_t Hash) const {
1065   switch (Ctx->getTargetTriple().getObjectFormat()) {
1066   case Triple::ELF:
1067     return Ctx->getELFSection(Name, ELF::SHT_PROGBITS, ELF::SHF_GROUP, 0,
1068                               utostr(Hash), /*IsComdat=*/true);
1069   case Triple::Wasm:
1070     return Ctx->getWasmSection(Name, SectionKind::getMetadata(), 0,
1071                                utostr(Hash), MCContext::GenericSectionID);
1072   case Triple::MachO:
1073   case Triple::COFF:
1074   case Triple::GOFF:
1075   case Triple::SPIRV:
1076   case Triple::XCOFF:
1077   case Triple::DXContainer:
1078   case Triple::UnknownObjectFormat:
1079     report_fatal_error("Cannot get DWARF comdat section for this object file "
1080                        "format: not implemented.");
1081     break;
1082   }
1083   llvm_unreachable("Unknown ObjectFormatType");
1084 }
1085 
1086 MCSection *
1087 MCObjectFileInfo::getStackSizesSection(const MCSection &TextSec) const {
1088   if (Ctx->getObjectFileType() != MCContext::IsELF)
1089     return StackSizesSection;
1090 
1091   const MCSectionELF &ElfSec = static_cast<const MCSectionELF &>(TextSec);
1092   unsigned Flags = ELF::SHF_LINK_ORDER;
1093   StringRef GroupName;
1094   if (const MCSymbol *Group = ElfSec.getGroup()) {
1095     GroupName = Group->getName();
1096     Flags |= ELF::SHF_GROUP;
1097   }
1098 
1099   return Ctx->getELFSection(".stack_sizes", ELF::SHT_PROGBITS, Flags, 0,
1100                             GroupName, true, ElfSec.getUniqueID(),
1101                             cast<MCSymbolELF>(TextSec.getBeginSymbol()));
1102 }
1103 
1104 MCSection *
1105 MCObjectFileInfo::getBBAddrMapSection(const MCSection &TextSec) const {
1106   if (Ctx->getObjectFileType() != MCContext::IsELF)
1107     return nullptr;
1108 
1109   const MCSectionELF &ElfSec = static_cast<const MCSectionELF &>(TextSec);
1110   unsigned Flags = ELF::SHF_LINK_ORDER;
1111   StringRef GroupName;
1112   if (const MCSymbol *Group = ElfSec.getGroup()) {
1113     GroupName = Group->getName();
1114     Flags |= ELF::SHF_GROUP;
1115   }
1116 
1117   // Use the text section's begin symbol and unique ID to create a separate
1118   // .llvm_bb_addr_map section associated with every unique text section.
1119   return Ctx->getELFSection(".llvm_bb_addr_map", ELF::SHT_LLVM_BB_ADDR_MAP,
1120                             Flags, 0, GroupName, true, ElfSec.getUniqueID(),
1121                             cast<MCSymbolELF>(TextSec.getBeginSymbol()));
1122 }
1123 
1124 MCSection *
1125 MCObjectFileInfo::getPseudoProbeSection(const MCSection *TextSec) const {
1126   if (Ctx->getObjectFileType() == MCContext::IsELF) {
1127     const auto *ElfSec = static_cast<const MCSectionELF *>(TextSec);
1128     // Create a separate section for probes that comes with a comdat function.
1129     if (const MCSymbol *Group = ElfSec->getGroup()) {
1130       auto *S = static_cast<MCSectionELF *>(PseudoProbeSection);
1131       auto Flags = S->getFlags() | ELF::SHF_GROUP;
1132       return Ctx->getELFSection(S->getName(), S->getType(), Flags,
1133                                 S->getEntrySize(), Group->getName(),
1134                                 /*IsComdat=*/true);
1135     }
1136   }
1137   return PseudoProbeSection;
1138 }
1139 
1140 MCSection *
1141 MCObjectFileInfo::getPseudoProbeDescSection(StringRef FuncName) const {
1142   if (Ctx->getObjectFileType() == MCContext::IsELF) {
1143     // Create a separate comdat group for each function's descriptor in order
1144     // for the linker to deduplicate. The duplication, must be from different
1145     // tranlation unit, can come from:
1146     //  1. Inline functions defined in header files;
1147     //  2. ThinLTO imported funcions;
1148     //  3. Weak-linkage definitions.
1149     // Use a concatenation of the section name and the function name as the
1150     // group name so that descriptor-only groups won't be folded with groups of
1151     // code.
1152     if (Ctx->getTargetTriple().supportsCOMDAT() && !FuncName.empty()) {
1153       auto *S = static_cast<MCSectionELF *>(PseudoProbeDescSection);
1154       auto Flags = S->getFlags() | ELF::SHF_GROUP;
1155       return Ctx->getELFSection(S->getName(), S->getType(), Flags,
1156                                 S->getEntrySize(),
1157                                 S->getName() + "_" + FuncName,
1158                                 /*IsComdat=*/true);
1159     }
1160   }
1161   return PseudoProbeDescSection;
1162 }
1163