1 //===-- MObjectFileInfo.cpp - Object File Information ---------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #include "llvm/MC/MCObjectFileInfo.h" 11 #include "llvm/ADT/StringExtras.h" 12 #include "llvm/ADT/Triple.h" 13 #include "llvm/MC/MCAsmInfo.h" 14 #include "llvm/MC/MCContext.h" 15 #include "llvm/MC/MCSection.h" 16 #include "llvm/MC/MCSectionCOFF.h" 17 #include "llvm/MC/MCSectionELF.h" 18 #include "llvm/MC/MCSectionMachO.h" 19 using namespace llvm; 20 21 static bool useCompactUnwind(const Triple &T) { 22 // Only on darwin. 23 if (!T.isOSDarwin()) 24 return false; 25 26 // aarch64 always has it. 27 if (T.getArch() == Triple::aarch64) 28 return true; 29 30 // Use it on newer version of OS X. 31 if (T.isMacOSX() && !T.isMacOSXVersionLT(10, 6)) 32 return true; 33 34 // And the iOS simulator. 35 if (T.isiOS() && 36 (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86)) 37 return true; 38 39 return false; 40 } 41 42 void MCObjectFileInfo::initMachOMCObjectFileInfo(Triple T) { 43 // MachO 44 SupportsWeakOmittedEHFrame = false; 45 46 if (T.isOSDarwin() && T.getArch() == Triple::aarch64) 47 SupportsCompactUnwindWithoutEHFrame = true; 48 49 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel 50 | dwarf::DW_EH_PE_sdata4; 51 LSDAEncoding = FDECFIEncoding = dwarf::DW_EH_PE_pcrel; 52 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 53 dwarf::DW_EH_PE_sdata4; 54 55 // .comm doesn't support alignment before Leopard. 56 if (T.isMacOSX() && T.isMacOSXVersionLT(10, 5)) 57 CommDirectiveSupportsAlignment = false; 58 59 TextSection // .text 60 = Ctx->getMachOSection("__TEXT", "__text", 61 MachO::S_ATTR_PURE_INSTRUCTIONS, 62 SectionKind::getText()); 63 DataSection // .data 64 = Ctx->getMachOSection("__DATA", "__data", 0, 65 SectionKind::getDataRel()); 66 67 // BSSSection might not be expected initialized on msvc. 68 BSSSection = nullptr; 69 70 TLSDataSection // .tdata 71 = Ctx->getMachOSection("__DATA", "__thread_data", 72 MachO::S_THREAD_LOCAL_REGULAR, 73 SectionKind::getDataRel()); 74 TLSBSSSection // .tbss 75 = Ctx->getMachOSection("__DATA", "__thread_bss", 76 MachO::S_THREAD_LOCAL_ZEROFILL, 77 SectionKind::getThreadBSS()); 78 79 // TODO: Verify datarel below. 80 TLSTLVSection // .tlv 81 = Ctx->getMachOSection("__DATA", "__thread_vars", 82 MachO::S_THREAD_LOCAL_VARIABLES, 83 SectionKind::getDataRel()); 84 85 TLSThreadInitSection 86 = Ctx->getMachOSection("__DATA", "__thread_init", 87 MachO::S_THREAD_LOCAL_INIT_FUNCTION_POINTERS, 88 SectionKind::getDataRel()); 89 90 CStringSection // .cstring 91 = Ctx->getMachOSection("__TEXT", "__cstring", 92 MachO::S_CSTRING_LITERALS, 93 SectionKind::getMergeable1ByteCString()); 94 UStringSection 95 = Ctx->getMachOSection("__TEXT","__ustring", 0, 96 SectionKind::getMergeable2ByteCString()); 97 FourByteConstantSection // .literal4 98 = Ctx->getMachOSection("__TEXT", "__literal4", 99 MachO::S_4BYTE_LITERALS, 100 SectionKind::getMergeableConst4()); 101 EightByteConstantSection // .literal8 102 = Ctx->getMachOSection("__TEXT", "__literal8", 103 MachO::S_8BYTE_LITERALS, 104 SectionKind::getMergeableConst8()); 105 106 SixteenByteConstantSection // .literal16 107 = Ctx->getMachOSection("__TEXT", "__literal16", 108 MachO::S_16BYTE_LITERALS, 109 SectionKind::getMergeableConst16()); 110 111 ReadOnlySection // .const 112 = Ctx->getMachOSection("__TEXT", "__const", 0, 113 SectionKind::getReadOnly()); 114 115 TextCoalSection 116 = Ctx->getMachOSection("__TEXT", "__textcoal_nt", 117 MachO::S_COALESCED | 118 MachO::S_ATTR_PURE_INSTRUCTIONS, 119 SectionKind::getText()); 120 ConstTextCoalSection 121 = Ctx->getMachOSection("__TEXT", "__const_coal", 122 MachO::S_COALESCED, 123 SectionKind::getReadOnly()); 124 ConstDataSection // .const_data 125 = Ctx->getMachOSection("__DATA", "__const", 0, 126 SectionKind::getReadOnlyWithRel()); 127 DataCoalSection 128 = Ctx->getMachOSection("__DATA","__datacoal_nt", 129 MachO::S_COALESCED, 130 SectionKind::getDataRel()); 131 DataCommonSection 132 = Ctx->getMachOSection("__DATA","__common", 133 MachO::S_ZEROFILL, 134 SectionKind::getBSS()); 135 DataBSSSection 136 = Ctx->getMachOSection("__DATA","__bss", MachO::S_ZEROFILL, 137 SectionKind::getBSS()); 138 139 140 LazySymbolPointerSection 141 = Ctx->getMachOSection("__DATA", "__la_symbol_ptr", 142 MachO::S_LAZY_SYMBOL_POINTERS, 143 SectionKind::getMetadata()); 144 NonLazySymbolPointerSection 145 = Ctx->getMachOSection("__DATA", "__nl_symbol_ptr", 146 MachO::S_NON_LAZY_SYMBOL_POINTERS, 147 SectionKind::getMetadata()); 148 149 if (RelocM == Reloc::Static) { 150 StaticCtorSection 151 = Ctx->getMachOSection("__TEXT", "__constructor", 0, 152 SectionKind::getDataRel()); 153 StaticDtorSection 154 = Ctx->getMachOSection("__TEXT", "__destructor", 0, 155 SectionKind::getDataRel()); 156 } else { 157 StaticCtorSection 158 = Ctx->getMachOSection("__DATA", "__mod_init_func", 159 MachO::S_MOD_INIT_FUNC_POINTERS, 160 SectionKind::getDataRel()); 161 StaticDtorSection 162 = Ctx->getMachOSection("__DATA", "__mod_term_func", 163 MachO::S_MOD_TERM_FUNC_POINTERS, 164 SectionKind::getDataRel()); 165 } 166 167 // Exception Handling. 168 LSDASection = Ctx->getMachOSection("__TEXT", "__gcc_except_tab", 0, 169 SectionKind::getReadOnlyWithRel()); 170 171 COFFDebugSymbolsSection = nullptr; 172 173 if (useCompactUnwind(T)) { 174 CompactUnwindSection = 175 Ctx->getMachOSection("__LD", "__compact_unwind", MachO::S_ATTR_DEBUG, 176 SectionKind::getReadOnly()); 177 178 if (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86) 179 CompactUnwindDwarfEHFrameOnly = 0x04000000; 180 else if (T.getArch() == Triple::aarch64) 181 CompactUnwindDwarfEHFrameOnly = 0x03000000; 182 } 183 184 // Debug Information. 185 DwarfAccelNamesSection = 186 Ctx->getMachOSection("__DWARF", "__apple_names", MachO::S_ATTR_DEBUG, 187 SectionKind::getMetadata(), "names_begin"); 188 DwarfAccelObjCSection = 189 Ctx->getMachOSection("__DWARF", "__apple_objc", MachO::S_ATTR_DEBUG, 190 SectionKind::getMetadata(), "objc_begin"); 191 // 16 character section limit... 192 DwarfAccelNamespaceSection = 193 Ctx->getMachOSection("__DWARF", "__apple_namespac", MachO::S_ATTR_DEBUG, 194 SectionKind::getMetadata(), "namespac_begin"); 195 DwarfAccelTypesSection = 196 Ctx->getMachOSection("__DWARF", "__apple_types", MachO::S_ATTR_DEBUG, 197 SectionKind::getMetadata(), "types_begin"); 198 199 DwarfAbbrevSection = 200 Ctx->getMachOSection("__DWARF", "__debug_abbrev", MachO::S_ATTR_DEBUG, 201 SectionKind::getMetadata(), "section_abbrev"); 202 DwarfInfoSection = 203 Ctx->getMachOSection("__DWARF", "__debug_info", MachO::S_ATTR_DEBUG, 204 SectionKind::getMetadata(), "section_info"); 205 DwarfLineSection = 206 Ctx->getMachOSection("__DWARF", "__debug_line", MachO::S_ATTR_DEBUG, 207 SectionKind::getMetadata(), "section_line"); 208 DwarfFrameSection = 209 Ctx->getMachOSection("__DWARF", "__debug_frame", MachO::S_ATTR_DEBUG, 210 SectionKind::getMetadata()); 211 DwarfPubNamesSection = 212 Ctx->getMachOSection("__DWARF", "__debug_pubnames", MachO::S_ATTR_DEBUG, 213 SectionKind::getMetadata()); 214 DwarfPubTypesSection = 215 Ctx->getMachOSection("__DWARF", "__debug_pubtypes", MachO::S_ATTR_DEBUG, 216 SectionKind::getMetadata()); 217 DwarfGnuPubNamesSection = 218 Ctx->getMachOSection("__DWARF", "__debug_gnu_pubn", MachO::S_ATTR_DEBUG, 219 SectionKind::getMetadata()); 220 DwarfGnuPubTypesSection = 221 Ctx->getMachOSection("__DWARF", "__debug_gnu_pubt", MachO::S_ATTR_DEBUG, 222 SectionKind::getMetadata()); 223 DwarfStrSection = 224 Ctx->getMachOSection("__DWARF", "__debug_str", MachO::S_ATTR_DEBUG, 225 SectionKind::getMetadata(), "info_string"); 226 DwarfLocSection = 227 Ctx->getMachOSection("__DWARF", "__debug_loc", MachO::S_ATTR_DEBUG, 228 SectionKind::getMetadata(), "section_debug_loc"); 229 DwarfARangesSection = 230 Ctx->getMachOSection("__DWARF", "__debug_aranges", MachO::S_ATTR_DEBUG, 231 SectionKind::getMetadata()); 232 DwarfRangesSection = 233 Ctx->getMachOSection("__DWARF", "__debug_ranges", MachO::S_ATTR_DEBUG, 234 SectionKind::getMetadata(), "debug_range"); 235 DwarfDebugInlineSection = 236 Ctx->getMachOSection("__DWARF", "__debug_inlined", MachO::S_ATTR_DEBUG, 237 SectionKind::getMetadata()); 238 StackMapSection = Ctx->getMachOSection("__LLVM_STACKMAPS", "__llvm_stackmaps", 239 0, SectionKind::getMetadata()); 240 241 FaultMapSection = Ctx->getMachOSection("__LLVM_FAULTMAPS", "__llvm_faultmaps", 242 0, SectionKind::getMetadata()); 243 244 TLSExtraDataSection = TLSTLVSection; 245 } 246 247 void MCObjectFileInfo::initELFMCObjectFileInfo(Triple T) { 248 switch (T.getArch()) { 249 case Triple::mips: 250 case Triple::mipsel: 251 FDECFIEncoding = dwarf::DW_EH_PE_sdata4; 252 break; 253 case Triple::mips64: 254 case Triple::mips64el: 255 FDECFIEncoding = dwarf::DW_EH_PE_sdata8; 256 break; 257 case Triple::x86_64: 258 FDECFIEncoding = dwarf::DW_EH_PE_pcrel | 259 ((CMModel == CodeModel::Large) ? dwarf::DW_EH_PE_sdata8 260 : dwarf::DW_EH_PE_sdata4); 261 262 break; 263 default: 264 FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 265 break; 266 } 267 268 switch (T.getArch()) { 269 case Triple::arm: 270 case Triple::armeb: 271 case Triple::thumb: 272 case Triple::thumbeb: 273 if (Ctx->getAsmInfo()->getExceptionHandlingType() == ExceptionHandling::ARM) 274 break; 275 // Fallthrough if not using EHABI 276 case Triple::ppc: 277 case Triple::x86: 278 PersonalityEncoding = (RelocM == Reloc::PIC_) 279 ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 280 : dwarf::DW_EH_PE_absptr; 281 LSDAEncoding = (RelocM == Reloc::PIC_) 282 ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 283 : dwarf::DW_EH_PE_absptr; 284 TTypeEncoding = (RelocM == Reloc::PIC_) 285 ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 286 : dwarf::DW_EH_PE_absptr; 287 break; 288 case Triple::x86_64: 289 if (RelocM == Reloc::PIC_) { 290 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 291 ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 292 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 293 LSDAEncoding = dwarf::DW_EH_PE_pcrel | 294 (CMModel == CodeModel::Small 295 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 296 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 297 ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 298 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 299 } else { 300 PersonalityEncoding = 301 (CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 302 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 303 LSDAEncoding = (CMModel == CodeModel::Small) 304 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 305 TTypeEncoding = (CMModel == CodeModel::Small) 306 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 307 } 308 break; 309 case Triple::aarch64: 310 case Triple::aarch64_be: 311 // The small model guarantees static code/data size < 4GB, but not where it 312 // will be in memory. Most of these could end up >2GB away so even a signed 313 // pc-relative 32-bit address is insufficient, theoretically. 314 if (RelocM == Reloc::PIC_) { 315 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 316 dwarf::DW_EH_PE_sdata8; 317 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8; 318 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 319 dwarf::DW_EH_PE_sdata8; 320 } else { 321 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 322 LSDAEncoding = dwarf::DW_EH_PE_absptr; 323 TTypeEncoding = dwarf::DW_EH_PE_absptr; 324 } 325 break; 326 case Triple::mips: 327 case Triple::mipsel: 328 case Triple::mips64: 329 case Triple::mips64el: 330 // MIPS uses indirect pointer to refer personality functions and types, so 331 // that the eh_frame section can be read-only. DW.ref.personality will be 332 // generated for relocation. 333 PersonalityEncoding = dwarf::DW_EH_PE_indirect; 334 // FIXME: The N64 ABI probably ought to use DW_EH_PE_sdata8 but we can't 335 // identify N64 from just a triple. 336 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 337 dwarf::DW_EH_PE_sdata4; 338 // We don't support PC-relative LSDA references in GAS so we use the default 339 // DW_EH_PE_absptr for those. 340 break; 341 case Triple::ppc64: 342 case Triple::ppc64le: 343 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 344 dwarf::DW_EH_PE_udata8; 345 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8; 346 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 347 dwarf::DW_EH_PE_udata8; 348 break; 349 case Triple::sparcel: 350 case Triple::sparc: 351 if (RelocM == Reloc::PIC_) { 352 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 353 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 354 dwarf::DW_EH_PE_sdata4; 355 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 356 dwarf::DW_EH_PE_sdata4; 357 } else { 358 LSDAEncoding = dwarf::DW_EH_PE_absptr; 359 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 360 TTypeEncoding = dwarf::DW_EH_PE_absptr; 361 } 362 break; 363 case Triple::sparcv9: 364 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 365 if (RelocM == Reloc::PIC_) { 366 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 367 dwarf::DW_EH_PE_sdata4; 368 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 369 dwarf::DW_EH_PE_sdata4; 370 } else { 371 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 372 TTypeEncoding = dwarf::DW_EH_PE_absptr; 373 } 374 break; 375 case Triple::systemz: 376 // All currently-defined code models guarantee that 4-byte PC-relative 377 // values will be in range. 378 if (RelocM == Reloc::PIC_) { 379 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 380 dwarf::DW_EH_PE_sdata4; 381 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 382 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 383 dwarf::DW_EH_PE_sdata4; 384 } else { 385 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 386 LSDAEncoding = dwarf::DW_EH_PE_absptr; 387 TTypeEncoding = dwarf::DW_EH_PE_absptr; 388 } 389 break; 390 default: 391 break; 392 } 393 394 // Solaris requires different flags for .eh_frame to seemingly every other 395 // platform. 396 EHSectionType = ELF::SHT_PROGBITS; 397 EHSectionFlags = ELF::SHF_ALLOC; 398 if (T.isOSSolaris()) { 399 if (T.getArch() == Triple::x86_64) 400 EHSectionType = ELF::SHT_X86_64_UNWIND; 401 else 402 EHSectionFlags |= ELF::SHF_WRITE; 403 } 404 405 406 // ELF 407 BSSSection = Ctx->getELFSection(".bss", ELF::SHT_NOBITS, 408 ELF::SHF_WRITE | ELF::SHF_ALLOC); 409 410 TextSection = Ctx->getELFSection(".text", ELF::SHT_PROGBITS, 411 ELF::SHF_EXECINSTR | ELF::SHF_ALLOC); 412 413 DataSection = Ctx->getELFSection(".data", ELF::SHT_PROGBITS, 414 ELF::SHF_WRITE | ELF::SHF_ALLOC); 415 416 ReadOnlySection = 417 Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 418 419 TLSDataSection = 420 Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS, 421 ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE); 422 423 TLSBSSSection = Ctx->getELFSection( 424 ".tbss", ELF::SHT_NOBITS, ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE); 425 426 DataRelSection = Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS, 427 ELF::SHF_ALLOC | ELF::SHF_WRITE); 428 429 DataRelLocalSection = Ctx->getELFSection(".data.rel.local", ELF::SHT_PROGBITS, 430 ELF::SHF_ALLOC | ELF::SHF_WRITE); 431 432 DataRelROSection = Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS, 433 ELF::SHF_ALLOC | ELF::SHF_WRITE); 434 435 DataRelROLocalSection = Ctx->getELFSection( 436 ".data.rel.ro.local", ELF::SHT_PROGBITS, ELF::SHF_ALLOC | ELF::SHF_WRITE); 437 438 MergeableConst4Section = 439 Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS, 440 ELF::SHF_ALLOC | ELF::SHF_MERGE, 4, ""); 441 442 MergeableConst8Section = 443 Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS, 444 ELF::SHF_ALLOC | ELF::SHF_MERGE, 8, ""); 445 446 MergeableConst16Section = 447 Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS, 448 ELF::SHF_ALLOC | ELF::SHF_MERGE, 16, ""); 449 450 StaticCtorSection = Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS, 451 ELF::SHF_ALLOC | ELF::SHF_WRITE); 452 453 StaticDtorSection = Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS, 454 ELF::SHF_ALLOC | ELF::SHF_WRITE); 455 456 // Exception Handling Sections. 457 458 // FIXME: We're emitting LSDA info into a readonly section on ELF, even though 459 // it contains relocatable pointers. In PIC mode, this is probably a big 460 // runtime hit for C++ apps. Either the contents of the LSDA need to be 461 // adjusted or this should be a data section. 462 LSDASection = Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS, 463 ELF::SHF_ALLOC); 464 465 COFFDebugSymbolsSection = nullptr; 466 467 // Debug Info Sections. 468 DwarfAbbrevSection = Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0, 469 "section_abbrev"); 470 DwarfInfoSection = 471 Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0, "section_info"); 472 DwarfLineSection = Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0); 473 DwarfFrameSection = Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0); 474 DwarfPubNamesSection = 475 Ctx->getELFSection(".debug_pubnames", ELF::SHT_PROGBITS, 0); 476 DwarfPubTypesSection = 477 Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0); 478 DwarfGnuPubNamesSection = 479 Ctx->getELFSection(".debug_gnu_pubnames", ELF::SHT_PROGBITS, 0); 480 DwarfGnuPubTypesSection = 481 Ctx->getELFSection(".debug_gnu_pubtypes", ELF::SHT_PROGBITS, 0); 482 DwarfStrSection = 483 Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS, 484 ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, ""); 485 DwarfLocSection = Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0); 486 DwarfARangesSection = 487 Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0); 488 DwarfRangesSection = 489 Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0, "debug_range"); 490 491 // DWARF5 Experimental Debug Info 492 493 // Accelerator Tables 494 DwarfAccelNamesSection = 495 Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0, "names_begin"); 496 DwarfAccelObjCSection = 497 Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0, "objc_begin"); 498 DwarfAccelNamespaceSection = Ctx->getELFSection( 499 ".apple_namespaces", ELF::SHT_PROGBITS, 0, "namespac_begin"); 500 DwarfAccelTypesSection = 501 Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0, "types_begin"); 502 503 // Fission Sections 504 DwarfInfoDWOSection = 505 Ctx->getELFSection(".debug_info.dwo", ELF::SHT_PROGBITS, 0); 506 DwarfTypesDWOSection = 507 Ctx->getELFSection(".debug_types.dwo", ELF::SHT_PROGBITS, 0); 508 DwarfAbbrevDWOSection = 509 Ctx->getELFSection(".debug_abbrev.dwo", ELF::SHT_PROGBITS, 0); 510 DwarfStrDWOSection = 511 Ctx->getELFSection(".debug_str.dwo", ELF::SHT_PROGBITS, 512 ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, ""); 513 DwarfLineDWOSection = 514 Ctx->getELFSection(".debug_line.dwo", ELF::SHT_PROGBITS, 0); 515 DwarfLocDWOSection = 516 Ctx->getELFSection(".debug_loc.dwo", ELF::SHT_PROGBITS, 0, "skel_loc"); 517 DwarfStrOffDWOSection = 518 Ctx->getELFSection(".debug_str_offsets.dwo", ELF::SHT_PROGBITS, 0); 519 DwarfAddrSection = 520 Ctx->getELFSection(".debug_addr", ELF::SHT_PROGBITS, 0, "addr_sec"); 521 522 StackMapSection = 523 Ctx->getELFSection(".llvm_stackmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 524 525 FaultMapSection = 526 Ctx->getELFSection(".llvm_faultmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 527 } 528 529 void MCObjectFileInfo::initCOFFMCObjectFileInfo(Triple T) { 530 bool IsWoA = T.getArch() == Triple::arm || T.getArch() == Triple::thumb; 531 532 CommDirectiveSupportsAlignment = true; 533 534 // COFF 535 BSSSection = Ctx->getCOFFSection( 536 ".bss", COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA | 537 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 538 SectionKind::getBSS()); 539 TextSection = Ctx->getCOFFSection( 540 ".text", 541 (IsWoA ? COFF::IMAGE_SCN_MEM_16BIT : (COFF::SectionCharacteristics)0) | 542 COFF::IMAGE_SCN_CNT_CODE | COFF::IMAGE_SCN_MEM_EXECUTE | 543 COFF::IMAGE_SCN_MEM_READ, 544 SectionKind::getText()); 545 DataSection = Ctx->getCOFFSection( 546 ".data", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ | 547 COFF::IMAGE_SCN_MEM_WRITE, 548 SectionKind::getDataRel()); 549 ReadOnlySection = Ctx->getCOFFSection( 550 ".rdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 551 SectionKind::getReadOnly()); 552 553 if (T.isKnownWindowsMSVCEnvironment() || T.isWindowsItaniumEnvironment()) { 554 StaticCtorSection = 555 Ctx->getCOFFSection(".CRT$XCU", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 556 COFF::IMAGE_SCN_MEM_READ, 557 SectionKind::getReadOnly()); 558 StaticDtorSection = 559 Ctx->getCOFFSection(".CRT$XTX", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 560 COFF::IMAGE_SCN_MEM_READ, 561 SectionKind::getReadOnly()); 562 } else { 563 StaticCtorSection = Ctx->getCOFFSection( 564 ".ctors", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 565 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 566 SectionKind::getDataRel()); 567 StaticDtorSection = Ctx->getCOFFSection( 568 ".dtors", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 569 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 570 SectionKind::getDataRel()); 571 } 572 573 // FIXME: We're emitting LSDA info into a readonly section on COFF, even 574 // though it contains relocatable pointers. In PIC mode, this is probably a 575 // big runtime hit for C++ apps. Either the contents of the LSDA need to be 576 // adjusted or this should be a data section. 577 assert(T.isOSWindows() && "Windows is the only supported COFF target"); 578 if (T.getArch() == Triple::x86_64) { 579 // On Windows 64 with SEH, the LSDA is emitted into the .xdata section 580 LSDASection = 0; 581 } else { 582 LSDASection = Ctx->getCOFFSection(".gcc_except_table", 583 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 584 COFF::IMAGE_SCN_MEM_READ, 585 SectionKind::getReadOnly()); 586 } 587 588 // Debug info. 589 COFFDebugSymbolsSection = 590 Ctx->getCOFFSection(".debug$S", COFF::IMAGE_SCN_MEM_DISCARDABLE | 591 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 592 COFF::IMAGE_SCN_MEM_READ, 593 SectionKind::getMetadata()); 594 595 DwarfAbbrevSection = Ctx->getCOFFSection( 596 ".debug_abbrev", 597 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 598 COFF::IMAGE_SCN_MEM_READ, 599 SectionKind::getMetadata(), "section_abbrev"); 600 DwarfInfoSection = Ctx->getCOFFSection( 601 ".debug_info", 602 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 603 COFF::IMAGE_SCN_MEM_READ, 604 SectionKind::getMetadata(), "section_info"); 605 DwarfLineSection = Ctx->getCOFFSection( 606 ".debug_line", 607 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 608 COFF::IMAGE_SCN_MEM_READ, 609 SectionKind::getMetadata(), "section_line"); 610 611 DwarfFrameSection = Ctx->getCOFFSection( 612 ".debug_frame", 613 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 614 COFF::IMAGE_SCN_MEM_READ, 615 SectionKind::getMetadata()); 616 DwarfPubNamesSection = Ctx->getCOFFSection( 617 ".debug_pubnames", 618 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 619 COFF::IMAGE_SCN_MEM_READ, 620 SectionKind::getMetadata()); 621 DwarfPubTypesSection = Ctx->getCOFFSection( 622 ".debug_pubtypes", 623 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 624 COFF::IMAGE_SCN_MEM_READ, 625 SectionKind::getMetadata()); 626 DwarfGnuPubNamesSection = Ctx->getCOFFSection( 627 ".debug_gnu_pubnames", 628 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 629 COFF::IMAGE_SCN_MEM_READ, 630 SectionKind::getMetadata()); 631 DwarfGnuPubTypesSection = Ctx->getCOFFSection( 632 ".debug_gnu_pubtypes", 633 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 634 COFF::IMAGE_SCN_MEM_READ, 635 SectionKind::getMetadata()); 636 DwarfStrSection = Ctx->getCOFFSection( 637 ".debug_str", 638 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 639 COFF::IMAGE_SCN_MEM_READ, 640 SectionKind::getMetadata(), "info_string"); 641 DwarfLocSection = Ctx->getCOFFSection( 642 ".debug_loc", 643 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 644 COFF::IMAGE_SCN_MEM_READ, 645 SectionKind::getMetadata(), "section_debug_loc"); 646 DwarfARangesSection = Ctx->getCOFFSection( 647 ".debug_aranges", 648 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 649 COFF::IMAGE_SCN_MEM_READ, 650 SectionKind::getMetadata()); 651 DwarfRangesSection = Ctx->getCOFFSection( 652 ".debug_ranges", 653 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 654 COFF::IMAGE_SCN_MEM_READ, 655 SectionKind::getMetadata(), "debug_range"); 656 DwarfInfoDWOSection = Ctx->getCOFFSection( 657 ".debug_info.dwo", 658 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 659 COFF::IMAGE_SCN_MEM_READ, 660 SectionKind::getMetadata(), "section_info_dwo"); 661 DwarfTypesDWOSection = Ctx->getCOFFSection( 662 ".debug_types.dwo", 663 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 664 COFF::IMAGE_SCN_MEM_READ, 665 SectionKind::getMetadata(), "section_types_dwo"); 666 DwarfAbbrevDWOSection = Ctx->getCOFFSection( 667 ".debug_abbrev.dwo", 668 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 669 COFF::IMAGE_SCN_MEM_READ, 670 SectionKind::getMetadata(), "section_abbrev_dwo"); 671 DwarfStrDWOSection = Ctx->getCOFFSection( 672 ".debug_str.dwo", 673 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 674 COFF::IMAGE_SCN_MEM_READ, 675 SectionKind::getMetadata(), "skel_string"); 676 DwarfLineDWOSection = Ctx->getCOFFSection( 677 ".debug_line.dwo", 678 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 679 COFF::IMAGE_SCN_MEM_READ, 680 SectionKind::getMetadata()); 681 DwarfLocDWOSection = Ctx->getCOFFSection( 682 ".debug_loc.dwo", 683 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 684 COFF::IMAGE_SCN_MEM_READ, 685 SectionKind::getMetadata(), "skel_loc"); 686 DwarfStrOffDWOSection = Ctx->getCOFFSection( 687 ".debug_str_offsets.dwo", 688 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 689 COFF::IMAGE_SCN_MEM_READ, 690 SectionKind::getMetadata()); 691 DwarfAddrSection = Ctx->getCOFFSection( 692 ".debug_addr", 693 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 694 COFF::IMAGE_SCN_MEM_READ, 695 SectionKind::getMetadata(), "addr_sec"); 696 DwarfAccelNamesSection = Ctx->getCOFFSection( 697 ".apple_names", 698 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 699 COFF::IMAGE_SCN_MEM_READ, 700 SectionKind::getMetadata(), "names_begin"); 701 DwarfAccelNamespaceSection = Ctx->getCOFFSection( 702 ".apple_namespaces", 703 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 704 COFF::IMAGE_SCN_MEM_READ, 705 SectionKind::getMetadata(), "namespac_begin"); 706 DwarfAccelTypesSection = Ctx->getCOFFSection( 707 ".apple_types", 708 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 709 COFF::IMAGE_SCN_MEM_READ, 710 SectionKind::getMetadata(), "types_begin"); 711 DwarfAccelObjCSection = Ctx->getCOFFSection( 712 ".apple_objc", 713 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 714 COFF::IMAGE_SCN_MEM_READ, 715 SectionKind::getMetadata(), "objc_begin"); 716 717 DrectveSection = Ctx->getCOFFSection( 718 ".drectve", COFF::IMAGE_SCN_LNK_INFO | COFF::IMAGE_SCN_LNK_REMOVE, 719 SectionKind::getMetadata()); 720 721 PDataSection = Ctx->getCOFFSection( 722 ".pdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 723 SectionKind::getDataRel()); 724 725 XDataSection = Ctx->getCOFFSection( 726 ".xdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 727 SectionKind::getDataRel()); 728 729 SXDataSection = Ctx->getCOFFSection(".sxdata", COFF::IMAGE_SCN_LNK_INFO, 730 SectionKind::getMetadata()); 731 732 TLSDataSection = Ctx->getCOFFSection( 733 ".tls$", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ | 734 COFF::IMAGE_SCN_MEM_WRITE, 735 SectionKind::getDataRel()); 736 737 StackMapSection = Ctx->getCOFFSection(".llvm_stackmaps", 738 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 739 COFF::IMAGE_SCN_MEM_READ, 740 SectionKind::getReadOnly()); 741 } 742 743 void MCObjectFileInfo::InitMCObjectFileInfo(const Triple &TheTriple, 744 Reloc::Model relocm, 745 CodeModel::Model cm, 746 MCContext &ctx) { 747 RelocM = relocm; 748 CMModel = cm; 749 Ctx = &ctx; 750 751 // Common. 752 CommDirectiveSupportsAlignment = true; 753 SupportsWeakOmittedEHFrame = true; 754 SupportsCompactUnwindWithoutEHFrame = false; 755 756 PersonalityEncoding = LSDAEncoding = FDECFIEncoding = TTypeEncoding = 757 dwarf::DW_EH_PE_absptr; 758 759 CompactUnwindDwarfEHFrameOnly = 0; 760 761 EHFrameSection = nullptr; // Created on demand. 762 CompactUnwindSection = nullptr; // Used only by selected targets. 763 DwarfAccelNamesSection = nullptr; // Used only by selected targets. 764 DwarfAccelObjCSection = nullptr; // Used only by selected targets. 765 DwarfAccelNamespaceSection = nullptr; // Used only by selected targets. 766 DwarfAccelTypesSection = nullptr; // Used only by selected targets. 767 768 TT = TheTriple; 769 770 Triple::ArchType Arch = TT.getArch(); 771 // FIXME: Checking for Arch here to filter out bogus triples such as 772 // cellspu-apple-darwin. Perhaps we should fix in Triple? 773 if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 774 Arch == Triple::arm || Arch == Triple::thumb || 775 Arch == Triple::aarch64 || 776 Arch == Triple::ppc || Arch == Triple::ppc64 || 777 Arch == Triple::UnknownArch) && 778 TT.isOSBinFormatMachO()) { 779 Env = IsMachO; 780 initMachOMCObjectFileInfo(TT); 781 } else if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 782 Arch == Triple::arm || Arch == Triple::thumb) && 783 (TT.isOSWindows() && TT.getObjectFormat() == Triple::COFF)) { 784 Env = IsCOFF; 785 initCOFFMCObjectFileInfo(TT); 786 } else { 787 Env = IsELF; 788 initELFMCObjectFileInfo(TT); 789 } 790 } 791 792 void MCObjectFileInfo::InitMCObjectFileInfo(StringRef TT, Reloc::Model RM, 793 CodeModel::Model CM, 794 MCContext &ctx) { 795 InitMCObjectFileInfo(Triple(TT), RM, CM, ctx); 796 } 797 798 MCSection *MCObjectFileInfo::getDwarfTypesSection(uint64_t Hash) const { 799 return Ctx->getELFSection(".debug_types", ELF::SHT_PROGBITS, ELF::SHF_GROUP, 800 0, utostr(Hash)); 801 } 802 803 void MCObjectFileInfo::InitEHFrameSection() { 804 if (Env == IsMachO) 805 EHFrameSection = 806 Ctx->getMachOSection("__TEXT", "__eh_frame", 807 MachO::S_COALESCED | 808 MachO::S_ATTR_NO_TOC | 809 MachO::S_ATTR_STRIP_STATIC_SYMS | 810 MachO::S_ATTR_LIVE_SUPPORT, 811 SectionKind::getReadOnly()); 812 else if (Env == IsELF) 813 EHFrameSection = 814 Ctx->getELFSection(".eh_frame", EHSectionType, EHSectionFlags); 815 else 816 EHFrameSection = 817 Ctx->getCOFFSection(".eh_frame", 818 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 819 COFF::IMAGE_SCN_MEM_READ | 820 COFF::IMAGE_SCN_MEM_WRITE, 821 SectionKind::getDataRel()); 822 } 823