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::arm64 || 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() && 47 (T.getArch() == Triple::arm64 || T.getArch() == Triple::aarch64)) 48 SupportsCompactUnwindWithoutEHFrame = true; 49 50 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel 51 | dwarf::DW_EH_PE_sdata4; 52 LSDAEncoding = FDECFIEncoding = dwarf::DW_EH_PE_pcrel; 53 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 54 dwarf::DW_EH_PE_sdata4; 55 56 // .comm doesn't support alignment before Leopard. 57 if (T.isMacOSX() && T.isMacOSXVersionLT(10, 5)) 58 CommDirectiveSupportsAlignment = false; 59 60 TextSection // .text 61 = Ctx->getMachOSection("__TEXT", "__text", 62 MachO::S_ATTR_PURE_INSTRUCTIONS, 63 SectionKind::getText()); 64 DataSection // .data 65 = Ctx->getMachOSection("__DATA", "__data", 0, 66 SectionKind::getDataRel()); 67 68 // BSSSection might not be expected initialized on msvc. 69 BSSSection = nullptr; 70 71 TLSDataSection // .tdata 72 = Ctx->getMachOSection("__DATA", "__thread_data", 73 MachO::S_THREAD_LOCAL_REGULAR, 74 SectionKind::getDataRel()); 75 TLSBSSSection // .tbss 76 = Ctx->getMachOSection("__DATA", "__thread_bss", 77 MachO::S_THREAD_LOCAL_ZEROFILL, 78 SectionKind::getThreadBSS()); 79 80 // TODO: Verify datarel below. 81 TLSTLVSection // .tlv 82 = Ctx->getMachOSection("__DATA", "__thread_vars", 83 MachO::S_THREAD_LOCAL_VARIABLES, 84 SectionKind::getDataRel()); 85 86 TLSThreadInitSection 87 = Ctx->getMachOSection("__DATA", "__thread_init", 88 MachO::S_THREAD_LOCAL_INIT_FUNCTION_POINTERS, 89 SectionKind::getDataRel()); 90 91 CStringSection // .cstring 92 = Ctx->getMachOSection("__TEXT", "__cstring", 93 MachO::S_CSTRING_LITERALS, 94 SectionKind::getMergeable1ByteCString()); 95 UStringSection 96 = Ctx->getMachOSection("__TEXT","__ustring", 0, 97 SectionKind::getMergeable2ByteCString()); 98 FourByteConstantSection // .literal4 99 = Ctx->getMachOSection("__TEXT", "__literal4", 100 MachO::S_4BYTE_LITERALS, 101 SectionKind::getMergeableConst4()); 102 EightByteConstantSection // .literal8 103 = Ctx->getMachOSection("__TEXT", "__literal8", 104 MachO::S_8BYTE_LITERALS, 105 SectionKind::getMergeableConst8()); 106 107 SixteenByteConstantSection // .literal16 108 = Ctx->getMachOSection("__TEXT", "__literal16", 109 MachO::S_16BYTE_LITERALS, 110 SectionKind::getMergeableConst16()); 111 112 ReadOnlySection // .const 113 = Ctx->getMachOSection("__TEXT", "__const", 0, 114 SectionKind::getReadOnly()); 115 116 TextCoalSection 117 = Ctx->getMachOSection("__TEXT", "__textcoal_nt", 118 MachO::S_COALESCED | 119 MachO::S_ATTR_PURE_INSTRUCTIONS, 120 SectionKind::getText()); 121 ConstTextCoalSection 122 = Ctx->getMachOSection("__TEXT", "__const_coal", 123 MachO::S_COALESCED, 124 SectionKind::getReadOnly()); 125 ConstDataSection // .const_data 126 = Ctx->getMachOSection("__DATA", "__const", 0, 127 SectionKind::getReadOnlyWithRel()); 128 DataCoalSection 129 = Ctx->getMachOSection("__DATA","__datacoal_nt", 130 MachO::S_COALESCED, 131 SectionKind::getDataRel()); 132 DataCommonSection 133 = Ctx->getMachOSection("__DATA","__common", 134 MachO::S_ZEROFILL, 135 SectionKind::getBSS()); 136 DataBSSSection 137 = Ctx->getMachOSection("__DATA","__bss", MachO::S_ZEROFILL, 138 SectionKind::getBSS()); 139 140 141 LazySymbolPointerSection 142 = Ctx->getMachOSection("__DATA", "__la_symbol_ptr", 143 MachO::S_LAZY_SYMBOL_POINTERS, 144 SectionKind::getMetadata()); 145 NonLazySymbolPointerSection 146 = Ctx->getMachOSection("__DATA", "__nl_symbol_ptr", 147 MachO::S_NON_LAZY_SYMBOL_POINTERS, 148 SectionKind::getMetadata()); 149 150 if (RelocM == Reloc::Static) { 151 StaticCtorSection 152 = Ctx->getMachOSection("__TEXT", "__constructor", 0, 153 SectionKind::getDataRel()); 154 StaticDtorSection 155 = Ctx->getMachOSection("__TEXT", "__destructor", 0, 156 SectionKind::getDataRel()); 157 } else { 158 StaticCtorSection 159 = Ctx->getMachOSection("__DATA", "__mod_init_func", 160 MachO::S_MOD_INIT_FUNC_POINTERS, 161 SectionKind::getDataRel()); 162 StaticDtorSection 163 = Ctx->getMachOSection("__DATA", "__mod_term_func", 164 MachO::S_MOD_TERM_FUNC_POINTERS, 165 SectionKind::getDataRel()); 166 } 167 168 // Exception Handling. 169 LSDASection = Ctx->getMachOSection("__TEXT", "__gcc_except_tab", 0, 170 SectionKind::getReadOnlyWithRel()); 171 172 COFFDebugSymbolsSection = nullptr; 173 174 if (useCompactUnwind(T)) { 175 CompactUnwindSection = 176 Ctx->getMachOSection("__LD", "__compact_unwind", MachO::S_ATTR_DEBUG, 177 SectionKind::getReadOnly()); 178 179 if (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86) 180 CompactUnwindDwarfEHFrameOnly = 0x04000000; 181 else if (T.getArch() == Triple::arm64 || T.getArch() == Triple::aarch64) 182 CompactUnwindDwarfEHFrameOnly = 0x03000000; 183 } 184 185 // Debug Information. 186 DwarfAccelNamesSection = 187 Ctx->getMachOSection("__DWARF", "__apple_names", 188 MachO::S_ATTR_DEBUG, 189 SectionKind::getMetadata()); 190 DwarfAccelObjCSection = 191 Ctx->getMachOSection("__DWARF", "__apple_objc", 192 MachO::S_ATTR_DEBUG, 193 SectionKind::getMetadata()); 194 // 16 character section limit... 195 DwarfAccelNamespaceSection = 196 Ctx->getMachOSection("__DWARF", "__apple_namespac", 197 MachO::S_ATTR_DEBUG, 198 SectionKind::getMetadata()); 199 DwarfAccelTypesSection = 200 Ctx->getMachOSection("__DWARF", "__apple_types", 201 MachO::S_ATTR_DEBUG, 202 SectionKind::getMetadata()); 203 204 DwarfAbbrevSection = 205 Ctx->getMachOSection("__DWARF", "__debug_abbrev", 206 MachO::S_ATTR_DEBUG, 207 SectionKind::getMetadata()); 208 DwarfInfoSection = 209 Ctx->getMachOSection("__DWARF", "__debug_info", 210 MachO::S_ATTR_DEBUG, 211 SectionKind::getMetadata()); 212 DwarfLineSection = 213 Ctx->getMachOSection("__DWARF", "__debug_line", 214 MachO::S_ATTR_DEBUG, 215 SectionKind::getMetadata()); 216 DwarfFrameSection = 217 Ctx->getMachOSection("__DWARF", "__debug_frame", 218 MachO::S_ATTR_DEBUG, 219 SectionKind::getMetadata()); 220 DwarfPubNamesSection = 221 Ctx->getMachOSection("__DWARF", "__debug_pubnames", 222 MachO::S_ATTR_DEBUG, 223 SectionKind::getMetadata()); 224 DwarfPubTypesSection = 225 Ctx->getMachOSection("__DWARF", "__debug_pubtypes", 226 MachO::S_ATTR_DEBUG, 227 SectionKind::getMetadata()); 228 DwarfGnuPubNamesSection = 229 Ctx->getMachOSection("__DWARF", "__debug_gnu_pubn", 230 MachO::S_ATTR_DEBUG, 231 SectionKind::getMetadata()); 232 DwarfGnuPubTypesSection = 233 Ctx->getMachOSection("__DWARF", "__debug_gnu_pubt", 234 MachO::S_ATTR_DEBUG, 235 SectionKind::getMetadata()); 236 DwarfStrSection = 237 Ctx->getMachOSection("__DWARF", "__debug_str", 238 MachO::S_ATTR_DEBUG, 239 SectionKind::getMetadata()); 240 DwarfLocSection = 241 Ctx->getMachOSection("__DWARF", "__debug_loc", 242 MachO::S_ATTR_DEBUG, 243 SectionKind::getMetadata()); 244 DwarfARangesSection = 245 Ctx->getMachOSection("__DWARF", "__debug_aranges", 246 MachO::S_ATTR_DEBUG, 247 SectionKind::getMetadata()); 248 DwarfRangesSection = 249 Ctx->getMachOSection("__DWARF", "__debug_ranges", 250 MachO::S_ATTR_DEBUG, 251 SectionKind::getMetadata()); 252 DwarfMacroInfoSection = 253 Ctx->getMachOSection("__DWARF", "__debug_macinfo", 254 MachO::S_ATTR_DEBUG, 255 SectionKind::getMetadata()); 256 DwarfDebugInlineSection = 257 Ctx->getMachOSection("__DWARF", "__debug_inlined", 258 MachO::S_ATTR_DEBUG, 259 SectionKind::getMetadata()); 260 StackMapSection = 261 Ctx->getMachOSection("__LLVM_STACKMAPS", "__llvm_stackmaps", 0, 262 SectionKind::getMetadata()); 263 264 TLSExtraDataSection = TLSTLVSection; 265 } 266 267 void MCObjectFileInfo::InitELFMCObjectFileInfo(Triple T) { 268 switch (T.getArch()) { 269 case Triple::mips: 270 case Triple::mipsel: 271 FDECFIEncoding = dwarf::DW_EH_PE_sdata4; 272 break; 273 case Triple::mips64: 274 case Triple::mips64el: 275 FDECFIEncoding = dwarf::DW_EH_PE_sdata8; 276 break; 277 default: 278 FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 279 break; 280 } 281 282 switch (T.getArch()) { 283 case Triple::arm: 284 case Triple::armeb: 285 case Triple::thumb: 286 case Triple::thumbeb: 287 if (Ctx->getAsmInfo()->getExceptionHandlingType() == ExceptionHandling::ARM) 288 break; 289 // Fallthrough if not using EHABI 290 case Triple::x86: 291 PersonalityEncoding = (RelocM == Reloc::PIC_) 292 ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 293 : dwarf::DW_EH_PE_absptr; 294 LSDAEncoding = (RelocM == Reloc::PIC_) 295 ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 296 : dwarf::DW_EH_PE_absptr; 297 TTypeEncoding = (RelocM == Reloc::PIC_) 298 ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 299 : dwarf::DW_EH_PE_absptr; 300 break; 301 case Triple::x86_64: 302 if (RelocM == Reloc::PIC_) { 303 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 304 ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 305 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 306 LSDAEncoding = dwarf::DW_EH_PE_pcrel | 307 (CMModel == CodeModel::Small 308 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 309 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 310 ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 311 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 312 } else { 313 PersonalityEncoding = 314 (CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 315 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 316 LSDAEncoding = (CMModel == CodeModel::Small) 317 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 318 TTypeEncoding = (CMModel == CodeModel::Small) 319 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 320 } 321 break; 322 case Triple::aarch64: 323 case Triple::aarch64_be: 324 case Triple::arm64: 325 case Triple::arm64_be: 326 // The small model guarantees static code/data size < 4GB, but not where it 327 // will be in memory. Most of these could end up >2GB away so even a signed 328 // pc-relative 32-bit address is insufficient, theoretically. 329 if (RelocM == Reloc::PIC_) { 330 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 331 dwarf::DW_EH_PE_sdata8; 332 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8; 333 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 334 dwarf::DW_EH_PE_sdata8; 335 } else { 336 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 337 LSDAEncoding = dwarf::DW_EH_PE_absptr; 338 TTypeEncoding = dwarf::DW_EH_PE_absptr; 339 } 340 break; 341 case Triple::mips: 342 case Triple::mipsel: 343 // MIPS uses indirect pointer to refer personality functions, so that the 344 // eh_frame section can be read-only. DW.ref.personality will be generated 345 // for relocation. 346 PersonalityEncoding = dwarf::DW_EH_PE_indirect; 347 break; 348 case Triple::ppc64: 349 case Triple::ppc64le: 350 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 351 dwarf::DW_EH_PE_udata8; 352 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8; 353 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 354 dwarf::DW_EH_PE_udata8; 355 break; 356 case Triple::sparc: 357 if (RelocM == Reloc::PIC_) { 358 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 359 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 360 dwarf::DW_EH_PE_sdata4; 361 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 362 dwarf::DW_EH_PE_sdata4; 363 } else { 364 LSDAEncoding = dwarf::DW_EH_PE_absptr; 365 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 366 TTypeEncoding = dwarf::DW_EH_PE_absptr; 367 } 368 break; 369 case Triple::sparcv9: 370 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 371 if (RelocM == Reloc::PIC_) { 372 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 373 dwarf::DW_EH_PE_sdata4; 374 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 375 dwarf::DW_EH_PE_sdata4; 376 } else { 377 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 378 TTypeEncoding = dwarf::DW_EH_PE_absptr; 379 } 380 break; 381 case Triple::systemz: 382 // All currently-defined code models guarantee that 4-byte PC-relative 383 // values will be in range. 384 if (RelocM == Reloc::PIC_) { 385 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 386 dwarf::DW_EH_PE_sdata4; 387 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 388 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 389 dwarf::DW_EH_PE_sdata4; 390 } else { 391 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 392 LSDAEncoding = dwarf::DW_EH_PE_absptr; 393 TTypeEncoding = dwarf::DW_EH_PE_absptr; 394 } 395 break; 396 default: 397 break; 398 } 399 400 // Solaris requires different flags for .eh_frame to seemingly every other 401 // platform. 402 EHSectionType = ELF::SHT_PROGBITS; 403 EHSectionFlags = ELF::SHF_ALLOC; 404 if (T.getOS() == Triple::Solaris) { 405 if (T.getArch() == Triple::x86_64) 406 EHSectionType = ELF::SHT_X86_64_UNWIND; 407 else 408 EHSectionFlags |= ELF::SHF_WRITE; 409 } 410 411 412 // ELF 413 BSSSection = 414 Ctx->getELFSection(".bss", ELF::SHT_NOBITS, 415 ELF::SHF_WRITE | ELF::SHF_ALLOC, 416 SectionKind::getBSS()); 417 418 TextSection = 419 Ctx->getELFSection(".text", ELF::SHT_PROGBITS, 420 ELF::SHF_EXECINSTR | 421 ELF::SHF_ALLOC, 422 SectionKind::getText()); 423 424 DataSection = 425 Ctx->getELFSection(".data", ELF::SHT_PROGBITS, 426 ELF::SHF_WRITE |ELF::SHF_ALLOC, 427 SectionKind::getDataRel()); 428 429 ReadOnlySection = 430 Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS, 431 ELF::SHF_ALLOC, 432 SectionKind::getReadOnly()); 433 434 TLSDataSection = 435 Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS, 436 ELF::SHF_ALLOC | ELF::SHF_TLS | 437 ELF::SHF_WRITE, 438 SectionKind::getThreadData()); 439 440 TLSBSSSection = 441 Ctx->getELFSection(".tbss", ELF::SHT_NOBITS, 442 ELF::SHF_ALLOC | ELF::SHF_TLS | 443 ELF::SHF_WRITE, 444 SectionKind::getThreadBSS()); 445 446 DataRelSection = 447 Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS, 448 ELF::SHF_ALLOC |ELF::SHF_WRITE, 449 SectionKind::getDataRel()); 450 451 DataRelLocalSection = 452 Ctx->getELFSection(".data.rel.local", ELF::SHT_PROGBITS, 453 ELF::SHF_ALLOC |ELF::SHF_WRITE, 454 SectionKind::getDataRelLocal()); 455 456 DataRelROSection = 457 Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS, 458 ELF::SHF_ALLOC |ELF::SHF_WRITE, 459 SectionKind::getReadOnlyWithRel()); 460 461 DataRelROLocalSection = 462 Ctx->getELFSection(".data.rel.ro.local", ELF::SHT_PROGBITS, 463 ELF::SHF_ALLOC |ELF::SHF_WRITE, 464 SectionKind::getReadOnlyWithRelLocal()); 465 466 MergeableConst4Section = 467 Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS, 468 ELF::SHF_ALLOC |ELF::SHF_MERGE, 469 SectionKind::getMergeableConst4()); 470 471 MergeableConst8Section = 472 Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS, 473 ELF::SHF_ALLOC |ELF::SHF_MERGE, 474 SectionKind::getMergeableConst8()); 475 476 MergeableConst16Section = 477 Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS, 478 ELF::SHF_ALLOC |ELF::SHF_MERGE, 479 SectionKind::getMergeableConst16()); 480 481 StaticCtorSection = 482 Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS, 483 ELF::SHF_ALLOC |ELF::SHF_WRITE, 484 SectionKind::getDataRel()); 485 486 StaticDtorSection = 487 Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS, 488 ELF::SHF_ALLOC |ELF::SHF_WRITE, 489 SectionKind::getDataRel()); 490 491 // Exception Handling Sections. 492 493 // FIXME: We're emitting LSDA info into a readonly section on ELF, even though 494 // it contains relocatable pointers. In PIC mode, this is probably a big 495 // runtime hit for C++ apps. Either the contents of the LSDA need to be 496 // adjusted or this should be a data section. 497 LSDASection = 498 Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS, 499 ELF::SHF_ALLOC, 500 SectionKind::getReadOnly()); 501 502 COFFDebugSymbolsSection = nullptr; 503 504 // Debug Info Sections. 505 DwarfAbbrevSection = 506 Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0, 507 SectionKind::getMetadata()); 508 DwarfInfoSection = 509 Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0, 510 SectionKind::getMetadata()); 511 DwarfLineSection = 512 Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0, 513 SectionKind::getMetadata()); 514 DwarfFrameSection = 515 Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0, 516 SectionKind::getMetadata()); 517 DwarfPubNamesSection = 518 Ctx->getELFSection(".debug_pubnames", ELF::SHT_PROGBITS, 0, 519 SectionKind::getMetadata()); 520 DwarfPubTypesSection = 521 Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0, 522 SectionKind::getMetadata()); 523 DwarfGnuPubNamesSection = 524 Ctx->getELFSection(".debug_gnu_pubnames", ELF::SHT_PROGBITS, 0, 525 SectionKind::getMetadata()); 526 DwarfGnuPubTypesSection = 527 Ctx->getELFSection(".debug_gnu_pubtypes", ELF::SHT_PROGBITS, 0, 528 SectionKind::getMetadata()); 529 DwarfStrSection = 530 Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS, 531 ELF::SHF_MERGE | ELF::SHF_STRINGS, 532 SectionKind::getMergeable1ByteCString()); 533 DwarfLocSection = 534 Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0, 535 SectionKind::getMetadata()); 536 DwarfARangesSection = 537 Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0, 538 SectionKind::getMetadata()); 539 DwarfRangesSection = 540 Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0, 541 SectionKind::getMetadata()); 542 DwarfMacroInfoSection = 543 Ctx->getELFSection(".debug_macinfo", ELF::SHT_PROGBITS, 0, 544 SectionKind::getMetadata()); 545 546 // DWARF5 Experimental Debug Info 547 548 // Accelerator Tables 549 DwarfAccelNamesSection = 550 Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0, 551 SectionKind::getMetadata()); 552 DwarfAccelObjCSection = 553 Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0, 554 SectionKind::getMetadata()); 555 DwarfAccelNamespaceSection = 556 Ctx->getELFSection(".apple_namespaces", ELF::SHT_PROGBITS, 0, 557 SectionKind::getMetadata()); 558 DwarfAccelTypesSection = 559 Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0, 560 SectionKind::getMetadata()); 561 562 // Fission Sections 563 DwarfInfoDWOSection = 564 Ctx->getELFSection(".debug_info.dwo", ELF::SHT_PROGBITS, 0, 565 SectionKind::getMetadata()); 566 DwarfAbbrevDWOSection = 567 Ctx->getELFSection(".debug_abbrev.dwo", ELF::SHT_PROGBITS, 0, 568 SectionKind::getMetadata()); 569 DwarfStrDWOSection = 570 Ctx->getELFSection(".debug_str.dwo", ELF::SHT_PROGBITS, 571 ELF::SHF_MERGE | ELF::SHF_STRINGS, 572 SectionKind::getMergeable1ByteCString()); 573 DwarfLineDWOSection = 574 Ctx->getELFSection(".debug_line.dwo", ELF::SHT_PROGBITS, 0, 575 SectionKind::getMetadata()); 576 DwarfLocDWOSection = 577 Ctx->getELFSection(".debug_loc.dwo", ELF::SHT_PROGBITS, 0, 578 SectionKind::getMetadata()); 579 DwarfStrOffDWOSection = 580 Ctx->getELFSection(".debug_str_offsets.dwo", ELF::SHT_PROGBITS, 0, 581 SectionKind::getMetadata()); 582 DwarfAddrSection = 583 Ctx->getELFSection(".debug_addr", ELF::SHT_PROGBITS, 0, 584 SectionKind::getMetadata()); 585 } 586 587 588 void MCObjectFileInfo::InitCOFFMCObjectFileInfo(Triple T) { 589 bool IsWoA = T.getArch() == Triple::arm || T.getArch() == Triple::thumb; 590 591 // The object file format cannot represent common symbols with explicit 592 // alignments. 593 CommDirectiveSupportsAlignment = false; 594 595 // COFF 596 BSSSection = 597 Ctx->getCOFFSection(".bss", 598 COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA | 599 COFF::IMAGE_SCN_MEM_READ | 600 COFF::IMAGE_SCN_MEM_WRITE, 601 SectionKind::getBSS()); 602 TextSection = 603 Ctx->getCOFFSection(".text", 604 (IsWoA ? COFF::IMAGE_SCN_MEM_16BIT 605 : (COFF::SectionCharacteristics)0) | 606 COFF::IMAGE_SCN_CNT_CODE | 607 COFF::IMAGE_SCN_MEM_EXECUTE | 608 COFF::IMAGE_SCN_MEM_READ, 609 SectionKind::getText()); 610 DataSection = 611 Ctx->getCOFFSection(".data", 612 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 613 COFF::IMAGE_SCN_MEM_READ | 614 COFF::IMAGE_SCN_MEM_WRITE, 615 SectionKind::getDataRel()); 616 ReadOnlySection = 617 Ctx->getCOFFSection(".rdata", 618 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 619 COFF::IMAGE_SCN_MEM_READ, 620 SectionKind::getReadOnly()); 621 622 if (T.isKnownWindowsMSVCEnvironment() || T.isWindowsItaniumEnvironment()) { 623 StaticCtorSection = 624 Ctx->getCOFFSection(".CRT$XCU", 625 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 626 COFF::IMAGE_SCN_MEM_READ, 627 SectionKind::getReadOnly()); 628 StaticDtorSection = 629 Ctx->getCOFFSection(".CRT$XTX", 630 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 631 COFF::IMAGE_SCN_MEM_READ, 632 SectionKind::getReadOnly()); 633 } else { 634 StaticCtorSection = 635 Ctx->getCOFFSection(".ctors", 636 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 637 COFF::IMAGE_SCN_MEM_READ | 638 COFF::IMAGE_SCN_MEM_WRITE, 639 SectionKind::getDataRel()); 640 StaticDtorSection = 641 Ctx->getCOFFSection(".dtors", 642 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 643 COFF::IMAGE_SCN_MEM_READ | 644 COFF::IMAGE_SCN_MEM_WRITE, 645 SectionKind::getDataRel()); 646 } 647 648 // FIXME: We're emitting LSDA info into a readonly section on COFF, even 649 // though it contains relocatable pointers. In PIC mode, this is probably a 650 // big runtime hit for C++ apps. Either the contents of the LSDA need to be 651 // adjusted or this should be a data section. 652 assert(T.isOSWindows() && "Windows is the only supported COFF target"); 653 if (T.getArch() == Triple::x86_64) { 654 // On Windows 64 with SEH, the LSDA is emitted into the .xdata section 655 LSDASection = 0; 656 } else { 657 LSDASection = Ctx->getCOFFSection(".gcc_except_table", 658 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 659 COFF::IMAGE_SCN_MEM_READ, 660 SectionKind::getReadOnly()); 661 } 662 663 // Debug info. 664 COFFDebugSymbolsSection = 665 Ctx->getCOFFSection(".debug$S", 666 COFF::IMAGE_SCN_MEM_DISCARDABLE | 667 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 668 COFF::IMAGE_SCN_MEM_READ, 669 SectionKind::getMetadata()); 670 671 DwarfAbbrevSection = 672 Ctx->getCOFFSection(".debug_abbrev", 673 COFF::IMAGE_SCN_MEM_DISCARDABLE | 674 COFF::IMAGE_SCN_MEM_READ, 675 SectionKind::getMetadata()); 676 DwarfInfoSection = 677 Ctx->getCOFFSection(".debug_info", 678 COFF::IMAGE_SCN_MEM_DISCARDABLE | 679 COFF::IMAGE_SCN_MEM_READ, 680 SectionKind::getMetadata()); 681 DwarfLineSection = 682 Ctx->getCOFFSection(".debug_line", 683 COFF::IMAGE_SCN_MEM_DISCARDABLE | 684 COFF::IMAGE_SCN_MEM_READ, 685 SectionKind::getMetadata()); 686 DwarfFrameSection = 687 Ctx->getCOFFSection(".debug_frame", 688 COFF::IMAGE_SCN_MEM_DISCARDABLE | 689 COFF::IMAGE_SCN_MEM_READ, 690 SectionKind::getMetadata()); 691 DwarfPubNamesSection = 692 Ctx->getCOFFSection(".debug_pubnames", 693 COFF::IMAGE_SCN_MEM_DISCARDABLE | 694 COFF::IMAGE_SCN_MEM_READ, 695 SectionKind::getMetadata()); 696 DwarfPubTypesSection = 697 Ctx->getCOFFSection(".debug_pubtypes", 698 COFF::IMAGE_SCN_MEM_DISCARDABLE | 699 COFF::IMAGE_SCN_MEM_READ, 700 SectionKind::getMetadata()); 701 DwarfGnuPubNamesSection = 702 Ctx->getCOFFSection(".debug_gnu_pubnames", 703 COFF::IMAGE_SCN_MEM_DISCARDABLE | 704 COFF::IMAGE_SCN_MEM_READ, 705 SectionKind::getMetadata()); 706 DwarfGnuPubTypesSection = 707 Ctx->getCOFFSection(".debug_gnu_pubtypes", 708 COFF::IMAGE_SCN_MEM_DISCARDABLE | 709 COFF::IMAGE_SCN_MEM_READ, 710 SectionKind::getMetadata()); 711 DwarfStrSection = 712 Ctx->getCOFFSection(".debug_str", 713 COFF::IMAGE_SCN_MEM_DISCARDABLE | 714 COFF::IMAGE_SCN_MEM_READ, 715 SectionKind::getMetadata()); 716 DwarfLocSection = 717 Ctx->getCOFFSection(".debug_loc", 718 COFF::IMAGE_SCN_MEM_DISCARDABLE | 719 COFF::IMAGE_SCN_MEM_READ, 720 SectionKind::getMetadata()); 721 DwarfARangesSection = 722 Ctx->getCOFFSection(".debug_aranges", 723 COFF::IMAGE_SCN_MEM_DISCARDABLE | 724 COFF::IMAGE_SCN_MEM_READ, 725 SectionKind::getMetadata()); 726 DwarfRangesSection = 727 Ctx->getCOFFSection(".debug_ranges", 728 COFF::IMAGE_SCN_MEM_DISCARDABLE | 729 COFF::IMAGE_SCN_MEM_READ, 730 SectionKind::getMetadata()); 731 DwarfMacroInfoSection = 732 Ctx->getCOFFSection(".debug_macinfo", 733 COFF::IMAGE_SCN_MEM_DISCARDABLE | 734 COFF::IMAGE_SCN_MEM_READ, 735 SectionKind::getMetadata()); 736 DwarfInfoDWOSection = 737 Ctx->getCOFFSection(".debug_info.dwo", 738 COFF::IMAGE_SCN_MEM_DISCARDABLE | 739 COFF::IMAGE_SCN_MEM_READ, 740 SectionKind::getMetadata()); 741 DwarfAbbrevDWOSection = 742 Ctx->getCOFFSection(".debug_abbrev.dwo", 743 COFF::IMAGE_SCN_MEM_DISCARDABLE | 744 COFF::IMAGE_SCN_MEM_READ, 745 SectionKind::getMetadata()); 746 DwarfStrDWOSection = 747 Ctx->getCOFFSection(".debug_str.dwo", 748 COFF::IMAGE_SCN_MEM_DISCARDABLE | 749 COFF::IMAGE_SCN_MEM_READ, 750 SectionKind::getMetadata()); 751 DwarfLineDWOSection = 752 Ctx->getCOFFSection(".debug_line.dwo", 753 COFF::IMAGE_SCN_MEM_DISCARDABLE | 754 COFF::IMAGE_SCN_MEM_READ, 755 SectionKind::getMetadata()); 756 DwarfLocDWOSection = 757 Ctx->getCOFFSection(".debug_loc.dwo", 758 COFF::IMAGE_SCN_MEM_DISCARDABLE | 759 COFF::IMAGE_SCN_MEM_READ, 760 SectionKind::getMetadata()); 761 DwarfStrOffDWOSection = 762 Ctx->getCOFFSection(".debug_str_offsets.dwo", 763 COFF::IMAGE_SCN_MEM_DISCARDABLE | 764 COFF::IMAGE_SCN_MEM_READ, 765 SectionKind::getMetadata()); 766 767 DwarfAddrSection = 768 Ctx->getCOFFSection(".debug_addr", 769 COFF::IMAGE_SCN_MEM_DISCARDABLE | 770 COFF::IMAGE_SCN_MEM_READ, 771 SectionKind::getMetadata()); 772 773 DrectveSection = 774 Ctx->getCOFFSection(".drectve", 775 COFF::IMAGE_SCN_LNK_INFO | 776 COFF::IMAGE_SCN_LNK_REMOVE, 777 SectionKind::getMetadata()); 778 779 PDataSection = 780 Ctx->getCOFFSection(".pdata", 781 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 782 COFF::IMAGE_SCN_MEM_READ, 783 SectionKind::getDataRel()); 784 785 XDataSection = 786 Ctx->getCOFFSection(".xdata", 787 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 788 COFF::IMAGE_SCN_MEM_READ, 789 SectionKind::getDataRel()); 790 791 TLSDataSection = 792 Ctx->getCOFFSection(".tls$", 793 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 794 COFF::IMAGE_SCN_MEM_READ | 795 COFF::IMAGE_SCN_MEM_WRITE, 796 SectionKind::getDataRel()); 797 } 798 799 void MCObjectFileInfo::InitMCObjectFileInfo(StringRef T, Reloc::Model relocm, 800 CodeModel::Model cm, 801 MCContext &ctx) { 802 RelocM = relocm; 803 CMModel = cm; 804 Ctx = &ctx; 805 806 // Common. 807 CommDirectiveSupportsAlignment = true; 808 SupportsWeakOmittedEHFrame = true; 809 SupportsCompactUnwindWithoutEHFrame = false; 810 811 PersonalityEncoding = LSDAEncoding = FDECFIEncoding = TTypeEncoding = 812 dwarf::DW_EH_PE_absptr; 813 814 CompactUnwindDwarfEHFrameOnly = 0; 815 816 EHFrameSection = nullptr; // Created on demand. 817 CompactUnwindSection = nullptr; // Used only by selected targets. 818 DwarfAccelNamesSection = nullptr; // Used only by selected targets. 819 DwarfAccelObjCSection = nullptr; // Used only by selected targets. 820 DwarfAccelNamespaceSection = nullptr; // Used only by selected targets. 821 DwarfAccelTypesSection = nullptr; // Used only by selected targets. 822 823 TT = Triple(T); 824 825 Triple::ArchType Arch = TT.getArch(); 826 // FIXME: Checking for Arch here to filter out bogus triples such as 827 // cellspu-apple-darwin. Perhaps we should fix in Triple? 828 if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 829 Arch == Triple::arm || Arch == Triple::thumb || 830 Arch == Triple::arm64 || Arch == Triple::aarch64 || 831 Arch == Triple::ppc || Arch == Triple::ppc64 || 832 Arch == Triple::UnknownArch) && 833 (TT.isOSDarwin() || TT.isOSBinFormatMachO())) { 834 Env = IsMachO; 835 InitMachOMCObjectFileInfo(TT); 836 } else if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 837 Arch == Triple::arm || Arch == Triple::thumb) && 838 (TT.isOSWindows() && TT.getObjectFormat() == Triple::COFF)) { 839 Env = IsCOFF; 840 InitCOFFMCObjectFileInfo(TT); 841 } else { 842 Env = IsELF; 843 InitELFMCObjectFileInfo(TT); 844 } 845 } 846 847 const MCSection *MCObjectFileInfo::getDwarfTypesSection(uint64_t Hash) const { 848 return Ctx->getELFSection(".debug_types", ELF::SHT_PROGBITS, ELF::SHF_GROUP, 849 SectionKind::getMetadata(), 0, utostr(Hash)); 850 } 851 852 const MCSection * 853 MCObjectFileInfo::getDwarfTypesDWOSection(uint64_t Hash) const { 854 return Ctx->getELFSection(".debug_types.dwo", ELF::SHT_PROGBITS, 855 ELF::SHF_GROUP, SectionKind::getMetadata(), 0, 856 utostr(Hash)); 857 } 858 859 void MCObjectFileInfo::InitEHFrameSection() { 860 if (Env == IsMachO) 861 EHFrameSection = 862 Ctx->getMachOSection("__TEXT", "__eh_frame", 863 MachO::S_COALESCED | 864 MachO::S_ATTR_NO_TOC | 865 MachO::S_ATTR_STRIP_STATIC_SYMS | 866 MachO::S_ATTR_LIVE_SUPPORT, 867 SectionKind::getReadOnly()); 868 else if (Env == IsELF) 869 EHFrameSection = 870 Ctx->getELFSection(".eh_frame", EHSectionType, 871 EHSectionFlags, 872 SectionKind::getDataRel()); 873 else 874 EHFrameSection = 875 Ctx->getCOFFSection(".eh_frame", 876 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 877 COFF::IMAGE_SCN_MEM_READ | 878 COFF::IMAGE_SCN_MEM_WRITE, 879 SectionKind::getDataRel()); 880 } 881
