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/MC/MCAsmInfo.h"
15 #include "llvm/MC/MCContext.h"
16 #include "llvm/MC/MCSection.h"
17 #include "llvm/MC/MCSectionCOFF.h"
18 #include "llvm/MC/MCSectionELF.h"
19 #include "llvm/MC/MCSectionMachO.h"
20 #include "llvm/MC/MCSectionWasm.h"
21 #include "llvm/MC/MCSectionXCOFF.h"
22 
23 using namespace llvm;
24 
25 static bool useCompactUnwind(const Triple &T) {
26   // Only on darwin.
27   if (!T.isOSDarwin())
28     return false;
29 
30   // aarch64 always has it.
31   if (T.getArch() == Triple::aarch64 || T.getArch() == Triple::aarch64_32)
32     return true;
33 
34   // armv7k always has it.
35   if (T.isWatchABI())
36     return true;
37 
38   // Use it on newer version of OS X.
39   if (T.isMacOSX() && !T.isMacOSXVersionLT(10, 6))
40     return true;
41 
42   // And the iOS simulator.
43   if (T.isiOS() && T.isX86())
44     return true;
45 
46   return false;
47 }
48 
49 void MCObjectFileInfo::initMachOMCObjectFileInfo(const Triple &T) {
50   // MachO
51   SupportsWeakOmittedEHFrame = false;
52 
53   EHFrameSection = Ctx->getMachOSection(
54       "__TEXT", "__eh_frame",
55       MachO::S_COALESCED | MachO::S_ATTR_NO_TOC |
56           MachO::S_ATTR_STRIP_STATIC_SYMS | MachO::S_ATTR_LIVE_SUPPORT,
57       SectionKind::getReadOnly());
58 
59   if (T.isOSDarwin() &&
60       (T.getArch() == Triple::aarch64 || T.getArch() == Triple::aarch64_32))
61     SupportsCompactUnwindWithoutEHFrame = true;
62 
63   if (T.isWatchABI())
64     OmitDwarfIfHaveCompactUnwind = true;
65 
66   FDECFIEncoding = dwarf::DW_EH_PE_pcrel;
67 
68   // .comm doesn't support alignment before Leopard.
69   if (T.isMacOSX() && T.isMacOSXVersionLT(10, 5))
70     CommDirectiveSupportsAlignment = false;
71 
72   TextSection // .text
73     = Ctx->getMachOSection("__TEXT", "__text",
74                            MachO::S_ATTR_PURE_INSTRUCTIONS,
75                            SectionKind::getText());
76   DataSection // .data
77       = Ctx->getMachOSection("__DATA", "__data", 0, SectionKind::getData());
78 
79   // BSSSection might not be expected initialized on msvc.
80   BSSSection = nullptr;
81 
82   TLSDataSection // .tdata
83       = Ctx->getMachOSection("__DATA", "__thread_data",
84                              MachO::S_THREAD_LOCAL_REGULAR,
85                              SectionKind::getData());
86   TLSBSSSection // .tbss
87     = Ctx->getMachOSection("__DATA", "__thread_bss",
88                            MachO::S_THREAD_LOCAL_ZEROFILL,
89                            SectionKind::getThreadBSS());
90 
91   // TODO: Verify datarel below.
92   TLSTLVSection // .tlv
93       = Ctx->getMachOSection("__DATA", "__thread_vars",
94                              MachO::S_THREAD_LOCAL_VARIABLES,
95                              SectionKind::getData());
96 
97   TLSThreadInitSection = Ctx->getMachOSection(
98       "__DATA", "__thread_init", MachO::S_THREAD_LOCAL_INIT_FUNCTION_POINTERS,
99       SectionKind::getData());
100 
101   CStringSection // .cstring
102     = Ctx->getMachOSection("__TEXT", "__cstring",
103                            MachO::S_CSTRING_LITERALS,
104                            SectionKind::getMergeable1ByteCString());
105   UStringSection
106     = Ctx->getMachOSection("__TEXT","__ustring", 0,
107                            SectionKind::getMergeable2ByteCString());
108   FourByteConstantSection // .literal4
109     = Ctx->getMachOSection("__TEXT", "__literal4",
110                            MachO::S_4BYTE_LITERALS,
111                            SectionKind::getMergeableConst4());
112   EightByteConstantSection // .literal8
113     = Ctx->getMachOSection("__TEXT", "__literal8",
114                            MachO::S_8BYTE_LITERALS,
115                            SectionKind::getMergeableConst8());
116 
117   SixteenByteConstantSection // .literal16
118       = Ctx->getMachOSection("__TEXT", "__literal16",
119                              MachO::S_16BYTE_LITERALS,
120                              SectionKind::getMergeableConst16());
121 
122   ReadOnlySection  // .const
123     = Ctx->getMachOSection("__TEXT", "__const", 0,
124                            SectionKind::getReadOnly());
125 
126   // If the target is not powerpc, map the coal sections to the non-coal
127   // sections.
128   //
129   // "__TEXT/__textcoal_nt" => section "__TEXT/__text"
130   // "__TEXT/__const_coal"  => section "__TEXT/__const"
131   // "__DATA/__datacoal_nt" => section "__DATA/__data"
132   Triple::ArchType ArchTy = T.getArch();
133 
134   ConstDataSection  // .const_data
135     = Ctx->getMachOSection("__DATA", "__const", 0,
136                            SectionKind::getReadOnlyWithRel());
137 
138   if (ArchTy == Triple::ppc || ArchTy == Triple::ppc64) {
139     TextCoalSection
140       = Ctx->getMachOSection("__TEXT", "__textcoal_nt",
141                              MachO::S_COALESCED |
142                              MachO::S_ATTR_PURE_INSTRUCTIONS,
143                              SectionKind::getText());
144     ConstTextCoalSection
145       = Ctx->getMachOSection("__TEXT", "__const_coal",
146                              MachO::S_COALESCED,
147                              SectionKind::getReadOnly());
148     DataCoalSection = Ctx->getMachOSection(
149         "__DATA", "__datacoal_nt", MachO::S_COALESCED, SectionKind::getData());
150     ConstDataCoalSection = DataCoalSection;
151   } else {
152     TextCoalSection = TextSection;
153     ConstTextCoalSection = ReadOnlySection;
154     DataCoalSection = DataSection;
155     ConstDataCoalSection = ConstDataSection;
156   }
157 
158   DataCommonSection
159     = Ctx->getMachOSection("__DATA","__common",
160                            MachO::S_ZEROFILL,
161                            SectionKind::getBSS());
162   DataBSSSection
163     = Ctx->getMachOSection("__DATA","__bss", MachO::S_ZEROFILL,
164                            SectionKind::getBSS());
165 
166 
167   LazySymbolPointerSection
168     = Ctx->getMachOSection("__DATA", "__la_symbol_ptr",
169                            MachO::S_LAZY_SYMBOL_POINTERS,
170                            SectionKind::getMetadata());
171   NonLazySymbolPointerSection
172     = Ctx->getMachOSection("__DATA", "__nl_symbol_ptr",
173                            MachO::S_NON_LAZY_SYMBOL_POINTERS,
174                            SectionKind::getMetadata());
175 
176   ThreadLocalPointerSection
177     = Ctx->getMachOSection("__DATA", "__thread_ptr",
178                            MachO::S_THREAD_LOCAL_VARIABLE_POINTERS,
179                            SectionKind::getMetadata());
180 
181   // Exception Handling.
182   LSDASection = Ctx->getMachOSection("__TEXT", "__gcc_except_tab", 0,
183                                      SectionKind::getReadOnlyWithRel());
184 
185   COFFDebugSymbolsSection = nullptr;
186   COFFDebugTypesSection = nullptr;
187   COFFGlobalTypeHashesSection = nullptr;
188 
189   if (useCompactUnwind(T)) {
190     CompactUnwindSection =
191         Ctx->getMachOSection("__LD", "__compact_unwind", MachO::S_ATTR_DEBUG,
192                              SectionKind::getReadOnly());
193 
194     if (T.isX86())
195       CompactUnwindDwarfEHFrameOnly = 0x04000000;  // UNWIND_X86_64_MODE_DWARF
196     else if (T.getArch() == Triple::aarch64 || T.getArch() == Triple::aarch64_32)
197       CompactUnwindDwarfEHFrameOnly = 0x03000000;  // UNWIND_ARM64_MODE_DWARF
198     else if (T.getArch() == Triple::arm || T.getArch() == Triple::thumb)
199       CompactUnwindDwarfEHFrameOnly = 0x04000000;  // UNWIND_ARM_MODE_DWARF
200   }
201 
202   // Debug Information.
203   DwarfDebugNamesSection =
204       Ctx->getMachOSection("__DWARF", "__debug_names", MachO::S_ATTR_DEBUG,
205                            SectionKind::getMetadata(), "debug_names_begin");
206   DwarfAccelNamesSection =
207       Ctx->getMachOSection("__DWARF", "__apple_names", MachO::S_ATTR_DEBUG,
208                            SectionKind::getMetadata(), "names_begin");
209   DwarfAccelObjCSection =
210       Ctx->getMachOSection("__DWARF", "__apple_objc", MachO::S_ATTR_DEBUG,
211                            SectionKind::getMetadata(), "objc_begin");
212   // 16 character section limit...
213   DwarfAccelNamespaceSection =
214       Ctx->getMachOSection("__DWARF", "__apple_namespac", MachO::S_ATTR_DEBUG,
215                            SectionKind::getMetadata(), "namespac_begin");
216   DwarfAccelTypesSection =
217       Ctx->getMachOSection("__DWARF", "__apple_types", MachO::S_ATTR_DEBUG,
218                            SectionKind::getMetadata(), "types_begin");
219 
220   DwarfSwiftASTSection =
221       Ctx->getMachOSection("__DWARF", "__swift_ast", MachO::S_ATTR_DEBUG,
222                            SectionKind::getMetadata());
223 
224   DwarfAbbrevSection =
225       Ctx->getMachOSection("__DWARF", "__debug_abbrev", MachO::S_ATTR_DEBUG,
226                            SectionKind::getMetadata(), "section_abbrev");
227   DwarfInfoSection =
228       Ctx->getMachOSection("__DWARF", "__debug_info", MachO::S_ATTR_DEBUG,
229                            SectionKind::getMetadata(), "section_info");
230   DwarfLineSection =
231       Ctx->getMachOSection("__DWARF", "__debug_line", MachO::S_ATTR_DEBUG,
232                            SectionKind::getMetadata(), "section_line");
233   DwarfLineStrSection =
234       Ctx->getMachOSection("__DWARF", "__debug_line_str", MachO::S_ATTR_DEBUG,
235                            SectionKind::getMetadata(), "section_line_str");
236   DwarfFrameSection =
237       Ctx->getMachOSection("__DWARF", "__debug_frame", MachO::S_ATTR_DEBUG,
238                            SectionKind::getMetadata());
239   DwarfPubNamesSection =
240       Ctx->getMachOSection("__DWARF", "__debug_pubnames", MachO::S_ATTR_DEBUG,
241                            SectionKind::getMetadata());
242   DwarfPubTypesSection =
243       Ctx->getMachOSection("__DWARF", "__debug_pubtypes", MachO::S_ATTR_DEBUG,
244                            SectionKind::getMetadata());
245   DwarfGnuPubNamesSection =
246       Ctx->getMachOSection("__DWARF", "__debug_gnu_pubn", MachO::S_ATTR_DEBUG,
247                            SectionKind::getMetadata());
248   DwarfGnuPubTypesSection =
249       Ctx->getMachOSection("__DWARF", "__debug_gnu_pubt", MachO::S_ATTR_DEBUG,
250                            SectionKind::getMetadata());
251   DwarfStrSection =
252       Ctx->getMachOSection("__DWARF", "__debug_str", MachO::S_ATTR_DEBUG,
253                            SectionKind::getMetadata(), "info_string");
254   DwarfStrOffSection =
255       Ctx->getMachOSection("__DWARF", "__debug_str_offs", MachO::S_ATTR_DEBUG,
256                            SectionKind::getMetadata(), "section_str_off");
257   DwarfAddrSection =
258       Ctx->getMachOSection("__DWARF", "__debug_addr", MachO::S_ATTR_DEBUG,
259                            SectionKind::getMetadata(), "section_info");
260   DwarfLocSection =
261       Ctx->getMachOSection("__DWARF", "__debug_loc", MachO::S_ATTR_DEBUG,
262                            SectionKind::getMetadata(), "section_debug_loc");
263   DwarfLoclistsSection =
264       Ctx->getMachOSection("__DWARF", "__debug_loclists", MachO::S_ATTR_DEBUG,
265                            SectionKind::getMetadata(), "section_debug_loc");
266 
267   DwarfARangesSection =
268       Ctx->getMachOSection("__DWARF", "__debug_aranges", MachO::S_ATTR_DEBUG,
269                            SectionKind::getMetadata());
270   DwarfRangesSection =
271       Ctx->getMachOSection("__DWARF", "__debug_ranges", MachO::S_ATTR_DEBUG,
272                            SectionKind::getMetadata(), "debug_range");
273   DwarfRnglistsSection =
274       Ctx->getMachOSection("__DWARF", "__debug_rnglists", MachO::S_ATTR_DEBUG,
275                            SectionKind::getMetadata(), "debug_range");
276   DwarfMacinfoSection =
277       Ctx->getMachOSection("__DWARF", "__debug_macinfo", MachO::S_ATTR_DEBUG,
278                            SectionKind::getMetadata(), "debug_macinfo");
279   DwarfDebugInlineSection =
280       Ctx->getMachOSection("__DWARF", "__debug_inlined", MachO::S_ATTR_DEBUG,
281                            SectionKind::getMetadata());
282   DwarfCUIndexSection =
283       Ctx->getMachOSection("__DWARF", "__debug_cu_index", MachO::S_ATTR_DEBUG,
284                            SectionKind::getMetadata());
285   DwarfTUIndexSection =
286       Ctx->getMachOSection("__DWARF", "__debug_tu_index", MachO::S_ATTR_DEBUG,
287                            SectionKind::getMetadata());
288   StackMapSection = Ctx->getMachOSection("__LLVM_STACKMAPS", "__llvm_stackmaps",
289                                          0, SectionKind::getMetadata());
290 
291   FaultMapSection = Ctx->getMachOSection("__LLVM_FAULTMAPS", "__llvm_faultmaps",
292                                          0, SectionKind::getMetadata());
293 
294   RemarksSection = Ctx->getMachOSection(
295       "__LLVM", "__remarks", MachO::S_ATTR_DEBUG, SectionKind::getMetadata());
296 
297   TLSExtraDataSection = TLSTLVSection;
298 }
299 
300 void MCObjectFileInfo::initELFMCObjectFileInfo(const Triple &T, bool Large) {
301   switch (T.getArch()) {
302   case Triple::mips:
303   case Triple::mipsel:
304   case Triple::mips64:
305   case Triple::mips64el:
306     // We cannot use DW_EH_PE_sdata8 for the large PositionIndependent case
307     // since there is no R_MIPS_PC64 relocation (only a 32-bit version).
308     if (PositionIndependent && !Large)
309       FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
310     else
311       FDECFIEncoding = Ctx->getAsmInfo()->getCodePointerSize() == 4
312                            ? dwarf::DW_EH_PE_sdata4
313                            : dwarf::DW_EH_PE_sdata8;
314     break;
315   case Triple::ppc64:
316   case Triple::ppc64le:
317   case Triple::x86_64:
318     FDECFIEncoding = dwarf::DW_EH_PE_pcrel |
319                      (Large ? dwarf::DW_EH_PE_sdata8 : dwarf::DW_EH_PE_sdata4);
320     break;
321   case Triple::bpfel:
322   case Triple::bpfeb:
323     FDECFIEncoding = dwarf::DW_EH_PE_sdata8;
324     break;
325   case Triple::hexagon:
326     FDECFIEncoding =
327         PositionIndependent ? dwarf::DW_EH_PE_pcrel : dwarf::DW_EH_PE_absptr;
328     break;
329   default:
330     FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
331     break;
332   }
333 
334   unsigned EHSectionType = T.getArch() == Triple::x86_64
335                                ? ELF::SHT_X86_64_UNWIND
336                                : ELF::SHT_PROGBITS;
337 
338   // Solaris requires different flags for .eh_frame to seemingly every other
339   // platform.
340   unsigned EHSectionFlags = ELF::SHF_ALLOC;
341   if (T.isOSSolaris() && T.getArch() != Triple::x86_64)
342     EHSectionFlags |= ELF::SHF_WRITE;
343 
344   // ELF
345   BSSSection = Ctx->getELFSection(".bss", ELF::SHT_NOBITS,
346                                   ELF::SHF_WRITE | ELF::SHF_ALLOC);
347 
348   TextSection = Ctx->getELFSection(".text", ELF::SHT_PROGBITS,
349                                    ELF::SHF_EXECINSTR | ELF::SHF_ALLOC);
350 
351   DataSection = Ctx->getELFSection(".data", ELF::SHT_PROGBITS,
352                                    ELF::SHF_WRITE | ELF::SHF_ALLOC);
353 
354   ReadOnlySection =
355       Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);
356 
357   TLSDataSection =
358       Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS,
359                          ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE);
360 
361   TLSBSSSection = Ctx->getELFSection(
362       ".tbss", ELF::SHT_NOBITS, ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE);
363 
364   DataRelROSection = Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS,
365                                         ELF::SHF_ALLOC | ELF::SHF_WRITE);
366 
367   MergeableConst4Section =
368       Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS,
369                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 4, "");
370 
371   MergeableConst8Section =
372       Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS,
373                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 8, "");
374 
375   MergeableConst16Section =
376       Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS,
377                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 16, "");
378 
379   MergeableConst32Section =
380       Ctx->getELFSection(".rodata.cst32", ELF::SHT_PROGBITS,
381                          ELF::SHF_ALLOC | ELF::SHF_MERGE, 32, "");
382 
383   // Exception Handling Sections.
384 
385   // FIXME: We're emitting LSDA info into a readonly section on ELF, even though
386   // it contains relocatable pointers.  In PIC mode, this is probably a big
387   // runtime hit for C++ apps.  Either the contents of the LSDA need to be
388   // adjusted or this should be a data section.
389   LSDASection = Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS,
390                                    ELF::SHF_ALLOC);
391 
392   COFFDebugSymbolsSection = nullptr;
393   COFFDebugTypesSection = nullptr;
394 
395   unsigned DebugSecType = ELF::SHT_PROGBITS;
396 
397   // MIPS .debug_* sections should have SHT_MIPS_DWARF section type
398   // to distinguish among sections contain DWARF and ECOFF debug formats.
399   // Sections with ECOFF debug format are obsoleted and marked by SHT_PROGBITS.
400   if (T.isMIPS())
401     DebugSecType = ELF::SHT_MIPS_DWARF;
402 
403   // Debug Info Sections.
404   DwarfAbbrevSection =
405       Ctx->getELFSection(".debug_abbrev", DebugSecType, 0);
406   DwarfInfoSection = Ctx->getELFSection(".debug_info", DebugSecType, 0);
407   DwarfLineSection = Ctx->getELFSection(".debug_line", DebugSecType, 0);
408   DwarfLineStrSection =
409       Ctx->getELFSection(".debug_line_str", DebugSecType,
410                          ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, "");
411   DwarfFrameSection = Ctx->getELFSection(".debug_frame", DebugSecType, 0);
412   DwarfPubNamesSection =
413       Ctx->getELFSection(".debug_pubnames", DebugSecType, 0);
414   DwarfPubTypesSection =
415       Ctx->getELFSection(".debug_pubtypes", DebugSecType, 0);
416   DwarfGnuPubNamesSection =
417       Ctx->getELFSection(".debug_gnu_pubnames", DebugSecType, 0);
418   DwarfGnuPubTypesSection =
419       Ctx->getELFSection(".debug_gnu_pubtypes", DebugSecType, 0);
420   DwarfStrSection =
421       Ctx->getELFSection(".debug_str", DebugSecType,
422                          ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, "");
423   DwarfLocSection = Ctx->getELFSection(".debug_loc", DebugSecType, 0);
424   DwarfARangesSection =
425       Ctx->getELFSection(".debug_aranges", DebugSecType, 0);
426   DwarfRangesSection =
427       Ctx->getELFSection(".debug_ranges", DebugSecType, 0);
428   DwarfMacinfoSection =
429       Ctx->getELFSection(".debug_macinfo", DebugSecType, 0);
430 
431   // DWARF5 Experimental Debug Info
432 
433   // Accelerator Tables
434   DwarfDebugNamesSection =
435       Ctx->getELFSection(".debug_names", ELF::SHT_PROGBITS, 0);
436   DwarfAccelNamesSection =
437       Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0);
438   DwarfAccelObjCSection =
439       Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0);
440   DwarfAccelNamespaceSection =
441       Ctx->getELFSection(".apple_namespaces", ELF::SHT_PROGBITS, 0);
442   DwarfAccelTypesSection =
443       Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0);
444 
445   // String Offset and Address Sections
446   DwarfStrOffSection =
447       Ctx->getELFSection(".debug_str_offsets", DebugSecType, 0);
448   DwarfAddrSection = Ctx->getELFSection(".debug_addr", DebugSecType, 0);
449   DwarfRnglistsSection = Ctx->getELFSection(".debug_rnglists", DebugSecType, 0);
450   DwarfLoclistsSection = Ctx->getELFSection(".debug_loclists", DebugSecType, 0);
451 
452   // Fission Sections
453   DwarfInfoDWOSection =
454       Ctx->getELFSection(".debug_info.dwo", DebugSecType, ELF::SHF_EXCLUDE);
455   DwarfTypesDWOSection =
456       Ctx->getELFSection(".debug_types.dwo", DebugSecType, ELF::SHF_EXCLUDE);
457   DwarfAbbrevDWOSection =
458       Ctx->getELFSection(".debug_abbrev.dwo", DebugSecType, ELF::SHF_EXCLUDE);
459   DwarfStrDWOSection = Ctx->getELFSection(
460       ".debug_str.dwo", DebugSecType,
461       ELF::SHF_MERGE | ELF::SHF_STRINGS | ELF::SHF_EXCLUDE, 1, "");
462   DwarfLineDWOSection =
463       Ctx->getELFSection(".debug_line.dwo", DebugSecType, ELF::SHF_EXCLUDE);
464   DwarfLocDWOSection =
465       Ctx->getELFSection(".debug_loc.dwo", DebugSecType, ELF::SHF_EXCLUDE);
466   DwarfStrOffDWOSection = Ctx->getELFSection(".debug_str_offsets.dwo",
467                                              DebugSecType, ELF::SHF_EXCLUDE);
468   DwarfRnglistsDWOSection =
469       Ctx->getELFSection(".debug_rnglists.dwo", DebugSecType, ELF::SHF_EXCLUDE);
470   DwarfMacinfoDWOSection =
471       Ctx->getELFSection(".debug_macinfo.dwo", DebugSecType, ELF::SHF_EXCLUDE);
472 
473   DwarfLoclistsDWOSection =
474       Ctx->getELFSection(".debug_loclists.dwo", DebugSecType, ELF::SHF_EXCLUDE);
475 
476   // DWP Sections
477   DwarfCUIndexSection =
478       Ctx->getELFSection(".debug_cu_index", DebugSecType, 0);
479   DwarfTUIndexSection =
480       Ctx->getELFSection(".debug_tu_index", DebugSecType, 0);
481 
482   StackMapSection =
483       Ctx->getELFSection(".llvm_stackmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);
484 
485   FaultMapSection =
486       Ctx->getELFSection(".llvm_faultmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC);
487 
488   EHFrameSection =
489       Ctx->getELFSection(".eh_frame", EHSectionType, EHSectionFlags);
490 
491   StackSizesSection = Ctx->getELFSection(".stack_sizes", ELF::SHT_PROGBITS, 0);
492 }
493 
494 void MCObjectFileInfo::initCOFFMCObjectFileInfo(const Triple &T) {
495   EHFrameSection =
496       Ctx->getCOFFSection(".eh_frame", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
497                                            COFF::IMAGE_SCN_MEM_READ,
498                           SectionKind::getData());
499 
500   // Set the `IMAGE_SCN_MEM_16BIT` flag when compiling for thumb mode.  This is
501   // used to indicate to the linker that the text segment contains thumb instructions
502   // and to set the ISA selection bit for calls accordingly.
503   const bool IsThumb = T.getArch() == Triple::thumb;
504 
505   CommDirectiveSupportsAlignment = true;
506 
507   // COFF
508   BSSSection = Ctx->getCOFFSection(
509       ".bss", COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA |
510                   COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE,
511       SectionKind::getBSS());
512   TextSection = Ctx->getCOFFSection(
513       ".text",
514       (IsThumb ? COFF::IMAGE_SCN_MEM_16BIT : (COFF::SectionCharacteristics)0) |
515           COFF::IMAGE_SCN_CNT_CODE | COFF::IMAGE_SCN_MEM_EXECUTE |
516           COFF::IMAGE_SCN_MEM_READ,
517       SectionKind::getText());
518   DataSection = Ctx->getCOFFSection(
519       ".data", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ |
520                    COFF::IMAGE_SCN_MEM_WRITE,
521       SectionKind::getData());
522   ReadOnlySection = Ctx->getCOFFSection(
523       ".rdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
524       SectionKind::getReadOnly());
525 
526   if (T.getArch() == Triple::x86_64 || T.getArch() == Triple::aarch64) {
527     // On Windows 64 with SEH, the LSDA is emitted into the .xdata section
528     LSDASection = nullptr;
529   } else {
530     LSDASection = Ctx->getCOFFSection(".gcc_except_table",
531                                       COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
532                                           COFF::IMAGE_SCN_MEM_READ,
533                                       SectionKind::getReadOnly());
534   }
535 
536   // Debug info.
537   COFFDebugSymbolsSection =
538       Ctx->getCOFFSection(".debug$S", (COFF::IMAGE_SCN_MEM_DISCARDABLE |
539                                        COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
540                                        COFF::IMAGE_SCN_MEM_READ),
541                           SectionKind::getMetadata());
542   COFFDebugTypesSection =
543       Ctx->getCOFFSection(".debug$T", (COFF::IMAGE_SCN_MEM_DISCARDABLE |
544                                        COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
545                                        COFF::IMAGE_SCN_MEM_READ),
546                           SectionKind::getMetadata());
547   COFFGlobalTypeHashesSection = Ctx->getCOFFSection(
548       ".debug$H",
549       (COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
550        COFF::IMAGE_SCN_MEM_READ),
551       SectionKind::getMetadata());
552 
553   DwarfAbbrevSection = Ctx->getCOFFSection(
554       ".debug_abbrev",
555       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
556           COFF::IMAGE_SCN_MEM_READ,
557       SectionKind::getMetadata(), "section_abbrev");
558   DwarfInfoSection = Ctx->getCOFFSection(
559       ".debug_info",
560       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
561           COFF::IMAGE_SCN_MEM_READ,
562       SectionKind::getMetadata(), "section_info");
563   DwarfLineSection = Ctx->getCOFFSection(
564       ".debug_line",
565       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
566           COFF::IMAGE_SCN_MEM_READ,
567       SectionKind::getMetadata(), "section_line");
568   DwarfLineStrSection = Ctx->getCOFFSection(
569       ".debug_line_str",
570       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
571           COFF::IMAGE_SCN_MEM_READ,
572       SectionKind::getMetadata(), "section_line_str");
573   DwarfFrameSection = Ctx->getCOFFSection(
574       ".debug_frame",
575       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
576           COFF::IMAGE_SCN_MEM_READ,
577       SectionKind::getMetadata());
578   DwarfPubNamesSection = Ctx->getCOFFSection(
579       ".debug_pubnames",
580       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
581           COFF::IMAGE_SCN_MEM_READ,
582       SectionKind::getMetadata());
583   DwarfPubTypesSection = Ctx->getCOFFSection(
584       ".debug_pubtypes",
585       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
586           COFF::IMAGE_SCN_MEM_READ,
587       SectionKind::getMetadata());
588   DwarfGnuPubNamesSection = Ctx->getCOFFSection(
589       ".debug_gnu_pubnames",
590       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
591           COFF::IMAGE_SCN_MEM_READ,
592       SectionKind::getMetadata());
593   DwarfGnuPubTypesSection = Ctx->getCOFFSection(
594       ".debug_gnu_pubtypes",
595       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
596           COFF::IMAGE_SCN_MEM_READ,
597       SectionKind::getMetadata());
598   DwarfStrSection = Ctx->getCOFFSection(
599       ".debug_str",
600       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
601           COFF::IMAGE_SCN_MEM_READ,
602       SectionKind::getMetadata(), "info_string");
603   DwarfStrOffSection = Ctx->getCOFFSection(
604       ".debug_str_offsets",
605       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
606           COFF::IMAGE_SCN_MEM_READ,
607       SectionKind::getMetadata(), "section_str_off");
608   DwarfLocSection = Ctx->getCOFFSection(
609       ".debug_loc",
610       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
611           COFF::IMAGE_SCN_MEM_READ,
612       SectionKind::getMetadata(), "section_debug_loc");
613   DwarfARangesSection = Ctx->getCOFFSection(
614       ".debug_aranges",
615       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
616           COFF::IMAGE_SCN_MEM_READ,
617       SectionKind::getMetadata());
618   DwarfRangesSection = Ctx->getCOFFSection(
619       ".debug_ranges",
620       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
621           COFF::IMAGE_SCN_MEM_READ,
622       SectionKind::getMetadata(), "debug_range");
623   DwarfMacinfoSection = Ctx->getCOFFSection(
624       ".debug_macinfo",
625       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
626           COFF::IMAGE_SCN_MEM_READ,
627       SectionKind::getMetadata(), "debug_macinfo");
628   DwarfMacinfoDWOSection = Ctx->getCOFFSection(
629       ".debug_macinfo.dwo",
630       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
631           COFF::IMAGE_SCN_MEM_READ,
632       SectionKind::getMetadata(), "debug_macinfo.dwo");
633   DwarfInfoDWOSection = Ctx->getCOFFSection(
634       ".debug_info.dwo",
635       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
636           COFF::IMAGE_SCN_MEM_READ,
637       SectionKind::getMetadata(), "section_info_dwo");
638   DwarfTypesDWOSection = Ctx->getCOFFSection(
639       ".debug_types.dwo",
640       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
641           COFF::IMAGE_SCN_MEM_READ,
642       SectionKind::getMetadata(), "section_types_dwo");
643   DwarfAbbrevDWOSection = Ctx->getCOFFSection(
644       ".debug_abbrev.dwo",
645       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
646           COFF::IMAGE_SCN_MEM_READ,
647       SectionKind::getMetadata(), "section_abbrev_dwo");
648   DwarfStrDWOSection = Ctx->getCOFFSection(
649       ".debug_str.dwo",
650       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
651           COFF::IMAGE_SCN_MEM_READ,
652       SectionKind::getMetadata(), "skel_string");
653   DwarfLineDWOSection = Ctx->getCOFFSection(
654       ".debug_line.dwo",
655       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
656           COFF::IMAGE_SCN_MEM_READ,
657       SectionKind::getMetadata());
658   DwarfLocDWOSection = Ctx->getCOFFSection(
659       ".debug_loc.dwo",
660       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
661           COFF::IMAGE_SCN_MEM_READ,
662       SectionKind::getMetadata(), "skel_loc");
663   DwarfStrOffDWOSection = Ctx->getCOFFSection(
664       ".debug_str_offsets.dwo",
665       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
666           COFF::IMAGE_SCN_MEM_READ,
667       SectionKind::getMetadata(), "section_str_off_dwo");
668   DwarfAddrSection = Ctx->getCOFFSection(
669       ".debug_addr",
670       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
671           COFF::IMAGE_SCN_MEM_READ,
672       SectionKind::getMetadata(), "addr_sec");
673   DwarfCUIndexSection = Ctx->getCOFFSection(
674       ".debug_cu_index",
675       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
676           COFF::IMAGE_SCN_MEM_READ,
677       SectionKind::getMetadata());
678   DwarfTUIndexSection = Ctx->getCOFFSection(
679       ".debug_tu_index",
680       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
681           COFF::IMAGE_SCN_MEM_READ,
682       SectionKind::getMetadata());
683   DwarfDebugNamesSection = Ctx->getCOFFSection(
684       ".debug_names",
685       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
686           COFF::IMAGE_SCN_MEM_READ,
687       SectionKind::getMetadata(), "debug_names_begin");
688   DwarfAccelNamesSection = Ctx->getCOFFSection(
689       ".apple_names",
690       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
691           COFF::IMAGE_SCN_MEM_READ,
692       SectionKind::getMetadata(), "names_begin");
693   DwarfAccelNamespaceSection = Ctx->getCOFFSection(
694       ".apple_namespaces",
695       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
696           COFF::IMAGE_SCN_MEM_READ,
697       SectionKind::getMetadata(), "namespac_begin");
698   DwarfAccelTypesSection = Ctx->getCOFFSection(
699       ".apple_types",
700       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
701           COFF::IMAGE_SCN_MEM_READ,
702       SectionKind::getMetadata(), "types_begin");
703   DwarfAccelObjCSection = Ctx->getCOFFSection(
704       ".apple_objc",
705       COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
706           COFF::IMAGE_SCN_MEM_READ,
707       SectionKind::getMetadata(), "objc_begin");
708 
709   DrectveSection = Ctx->getCOFFSection(
710       ".drectve", COFF::IMAGE_SCN_LNK_INFO | COFF::IMAGE_SCN_LNK_REMOVE,
711       SectionKind::getMetadata());
712 
713   PDataSection = Ctx->getCOFFSection(
714       ".pdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
715       SectionKind::getData());
716 
717   XDataSection = Ctx->getCOFFSection(
718       ".xdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ,
719       SectionKind::getData());
720 
721   SXDataSection = Ctx->getCOFFSection(".sxdata", COFF::IMAGE_SCN_LNK_INFO,
722                                       SectionKind::getMetadata());
723 
724   GFIDsSection = Ctx->getCOFFSection(".gfids$y",
725                                      COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
726                                          COFF::IMAGE_SCN_MEM_READ,
727                                      SectionKind::getMetadata());
728 
729   GLJMPSection = Ctx->getCOFFSection(".gljmp$y",
730                                      COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
731                                          COFF::IMAGE_SCN_MEM_READ,
732                                      SectionKind::getMetadata());
733 
734   TLSDataSection = Ctx->getCOFFSection(
735       ".tls$", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ |
736                    COFF::IMAGE_SCN_MEM_WRITE,
737       SectionKind::getData());
738 
739   StackMapSection = Ctx->getCOFFSection(".llvm_stackmaps",
740                                         COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
741                                             COFF::IMAGE_SCN_MEM_READ,
742                                         SectionKind::getReadOnly());
743 }
744 
745 void MCObjectFileInfo::initWasmMCObjectFileInfo(const Triple &T) {
746   TextSection = Ctx->getWasmSection(".text", SectionKind::getText());
747   DataSection = Ctx->getWasmSection(".data", SectionKind::getData());
748 
749   DwarfLineSection =
750       Ctx->getWasmSection(".debug_line", SectionKind::getMetadata());
751   DwarfLineStrSection =
752       Ctx->getWasmSection(".debug_line_str", SectionKind::getMetadata());
753   DwarfStrSection =
754       Ctx->getWasmSection(".debug_str", SectionKind::getMetadata());
755   DwarfLocSection =
756       Ctx->getWasmSection(".debug_loc", SectionKind::getMetadata());
757   DwarfAbbrevSection =
758       Ctx->getWasmSection(".debug_abbrev", SectionKind::getMetadata());
759   DwarfARangesSection = Ctx->getWasmSection(".debug_aranges", SectionKind::getMetadata());
760   DwarfRangesSection =
761       Ctx->getWasmSection(".debug_ranges", SectionKind::getMetadata());
762   DwarfMacinfoSection =
763       Ctx->getWasmSection(".debug_macinfo", SectionKind::getMetadata());
764   DwarfCUIndexSection = Ctx->getWasmSection(".debug_cu_index", SectionKind::getMetadata());
765   DwarfTUIndexSection = Ctx->getWasmSection(".debug_tu_index", SectionKind::getMetadata());
766   DwarfInfoSection =
767       Ctx->getWasmSection(".debug_info", SectionKind::getMetadata());
768   DwarfFrameSection = Ctx->getWasmSection(".debug_frame", SectionKind::getMetadata());
769   DwarfPubNamesSection = Ctx->getWasmSection(".debug_pubnames", SectionKind::getMetadata());
770   DwarfPubTypesSection = Ctx->getWasmSection(".debug_pubtypes", SectionKind::getMetadata());
771 
772   DwarfDebugNamesSection =
773       Ctx->getWasmSection(".debug_names", SectionKind::getMetadata());
774   DwarfStrOffSection =
775       Ctx->getWasmSection(".debug_str_offsets", SectionKind::getMetadata());
776   DwarfAddrSection =
777       Ctx->getWasmSection(".debug_addr", SectionKind::getMetadata());
778   DwarfRnglistsSection =
779       Ctx->getWasmSection(".debug_rnglists", SectionKind::getMetadata());
780   DwarfLoclistsSection =
781       Ctx->getWasmSection(".debug_loclists", SectionKind::getMetadata());
782 
783   // Wasm use data section for LSDA.
784   // TODO Consider putting each function's exception table in a separate
785   // section, as in -function-sections, to facilitate lld's --gc-section.
786   LSDASection = Ctx->getWasmSection(".rodata.gcc_except_table",
787                                     SectionKind::getReadOnlyWithRel());
788 
789   // TODO: Define more sections.
790 }
791 
792 void MCObjectFileInfo::initXCOFFMCObjectFileInfo(const Triple &T) {
793   // The default csect for program code. Functions without a specified section
794   // get placed into this csect. The choice of csect name is not a property of
795   // the ABI or object file format. For example, the XL compiler uses an unnamed
796   // csect for program code.
797   TextSection = Ctx->getXCOFFSection(
798       ".text", XCOFF::StorageMappingClass::XMC_PR, XCOFF::XTY_SD,
799       XCOFF::C_HIDEXT, SectionKind::getText());
800 
801   DataSection = Ctx->getXCOFFSection(
802       ".data", XCOFF::StorageMappingClass::XMC_RW, XCOFF::XTY_SD,
803       XCOFF::C_HIDEXT, SectionKind::getData());
804 
805   ReadOnlySection = Ctx->getXCOFFSection(
806       ".rodata", XCOFF::StorageMappingClass::XMC_RO, XCOFF::XTY_SD,
807       XCOFF::C_HIDEXT, SectionKind::getReadOnly());
808 }
809 
810 void MCObjectFileInfo::InitMCObjectFileInfo(const Triple &TheTriple, bool PIC,
811                                             MCContext &ctx,
812                                             bool LargeCodeModel) {
813   PositionIndependent = PIC;
814   Ctx = &ctx;
815 
816   // Common.
817   CommDirectiveSupportsAlignment = true;
818   SupportsWeakOmittedEHFrame = true;
819   SupportsCompactUnwindWithoutEHFrame = false;
820   OmitDwarfIfHaveCompactUnwind = false;
821 
822   FDECFIEncoding = dwarf::DW_EH_PE_absptr;
823 
824   CompactUnwindDwarfEHFrameOnly = 0;
825 
826   EHFrameSection = nullptr;             // Created on demand.
827   CompactUnwindSection = nullptr;       // Used only by selected targets.
828   DwarfAccelNamesSection = nullptr;     // Used only by selected targets.
829   DwarfAccelObjCSection = nullptr;      // Used only by selected targets.
830   DwarfAccelNamespaceSection = nullptr; // Used only by selected targets.
831   DwarfAccelTypesSection = nullptr;     // Used only by selected targets.
832 
833   TT = TheTriple;
834 
835   switch (TT.getObjectFormat()) {
836   case Triple::MachO:
837     Env = IsMachO;
838     initMachOMCObjectFileInfo(TT);
839     break;
840   case Triple::COFF:
841     if (!TT.isOSWindows())
842       report_fatal_error(
843           "Cannot initialize MC for non-Windows COFF object files.");
844 
845     Env = IsCOFF;
846     initCOFFMCObjectFileInfo(TT);
847     break;
848   case Triple::ELF:
849     Env = IsELF;
850     initELFMCObjectFileInfo(TT, LargeCodeModel);
851     break;
852   case Triple::Wasm:
853     Env = IsWasm;
854     initWasmMCObjectFileInfo(TT);
855     break;
856   case Triple::XCOFF:
857     Env = IsXCOFF;
858     initXCOFFMCObjectFileInfo(TT);
859     break;
860   case Triple::UnknownObjectFormat:
861     report_fatal_error("Cannot initialize MC for unknown object file format.");
862     break;
863   }
864 }
865 
866 MCSection *MCObjectFileInfo::getDwarfComdatSection(const char *Name,
867                                                    uint64_t Hash) const {
868   switch (TT.getObjectFormat()) {
869   case Triple::ELF:
870     return Ctx->getELFSection(Name, ELF::SHT_PROGBITS, ELF::SHF_GROUP, 0,
871                               utostr(Hash));
872   case Triple::MachO:
873   case Triple::COFF:
874   case Triple::Wasm:
875   case Triple::XCOFF:
876   case Triple::UnknownObjectFormat:
877     report_fatal_error("Cannot get DWARF comdat section for this object file "
878                        "format: not implemented.");
879     break;
880   }
881   llvm_unreachable("Unknown ObjectFormatType");
882 }
883 
884 MCSection *
885 MCObjectFileInfo::getStackSizesSection(const MCSection &TextSec) const {
886   if (Env != IsELF)
887     return StackSizesSection;
888 
889   const MCSectionELF &ElfSec = static_cast<const MCSectionELF &>(TextSec);
890   unsigned Flags = ELF::SHF_LINK_ORDER;
891   StringRef GroupName;
892   if (const MCSymbol *Group = ElfSec.getGroup()) {
893     GroupName = Group->getName();
894     Flags |= ELF::SHF_GROUP;
895   }
896 
897   const MCSymbol *Link = TextSec.getBeginSymbol();
898   auto It = StackSizesUniquing.insert({Link, StackSizesUniquing.size()});
899   unsigned UniqueID = It.first->second;
900 
901   return Ctx->getELFSection(".stack_sizes", ELF::SHT_PROGBITS, Flags, 0,
902                             GroupName, UniqueID, cast<MCSymbolELF>(Link));
903 }
904