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 #include "llvm/Support/COFF.h" 20 21 using namespace llvm; 22 23 static bool useCompactUnwind(const Triple &T) { 24 // Only on darwin. 25 if (!T.isOSDarwin()) 26 return false; 27 28 // aarch64 always has it. 29 if (T.getArch() == Triple::aarch64) 30 return true; 31 32 // Use it on newer version of OS X. 33 if (T.isMacOSX() && !T.isMacOSXVersionLT(10, 6)) 34 return true; 35 36 // And the iOS simulator. 37 if (T.isiOS() && 38 (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86)) 39 return true; 40 41 return false; 42 } 43 44 void MCObjectFileInfo::initMachOMCObjectFileInfo(Triple T) { 45 // MachO 46 SupportsWeakOmittedEHFrame = false; 47 48 if (T.isOSDarwin() && T.getArch() == Triple::aarch64) 49 SupportsCompactUnwindWithoutEHFrame = true; 50 51 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel 52 | dwarf::DW_EH_PE_sdata4; 53 LSDAEncoding = FDECFIEncoding = dwarf::DW_EH_PE_pcrel; 54 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 55 dwarf::DW_EH_PE_sdata4; 56 57 // .comm doesn't support alignment before Leopard. 58 if (T.isMacOSX() && T.isMacOSXVersionLT(10, 5)) 59 CommDirectiveSupportsAlignment = false; 60 61 TextSection // .text 62 = Ctx->getMachOSection("__TEXT", "__text", 63 MachO::S_ATTR_PURE_INSTRUCTIONS, 64 SectionKind::getText()); 65 DataSection // .data 66 = Ctx->getMachOSection("__DATA", "__data", 0, 67 SectionKind::getDataRel()); 68 69 // BSSSection might not be expected initialized on msvc. 70 BSSSection = nullptr; 71 72 TLSDataSection // .tdata 73 = Ctx->getMachOSection("__DATA", "__thread_data", 74 MachO::S_THREAD_LOCAL_REGULAR, 75 SectionKind::getDataRel()); 76 TLSBSSSection // .tbss 77 = Ctx->getMachOSection("__DATA", "__thread_bss", 78 MachO::S_THREAD_LOCAL_ZEROFILL, 79 SectionKind::getThreadBSS()); 80 81 // TODO: Verify datarel below. 82 TLSTLVSection // .tlv 83 = Ctx->getMachOSection("__DATA", "__thread_vars", 84 MachO::S_THREAD_LOCAL_VARIABLES, 85 SectionKind::getDataRel()); 86 87 TLSThreadInitSection 88 = Ctx->getMachOSection("__DATA", "__thread_init", 89 MachO::S_THREAD_LOCAL_INIT_FUNCTION_POINTERS, 90 SectionKind::getDataRel()); 91 92 CStringSection // .cstring 93 = Ctx->getMachOSection("__TEXT", "__cstring", 94 MachO::S_CSTRING_LITERALS, 95 SectionKind::getMergeable1ByteCString()); 96 UStringSection 97 = Ctx->getMachOSection("__TEXT","__ustring", 0, 98 SectionKind::getMergeable2ByteCString()); 99 FourByteConstantSection // .literal4 100 = Ctx->getMachOSection("__TEXT", "__literal4", 101 MachO::S_4BYTE_LITERALS, 102 SectionKind::getMergeableConst4()); 103 EightByteConstantSection // .literal8 104 = Ctx->getMachOSection("__TEXT", "__literal8", 105 MachO::S_8BYTE_LITERALS, 106 SectionKind::getMergeableConst8()); 107 108 SixteenByteConstantSection // .literal16 109 = Ctx->getMachOSection("__TEXT", "__literal16", 110 MachO::S_16BYTE_LITERALS, 111 SectionKind::getMergeableConst16()); 112 113 ReadOnlySection // .const 114 = Ctx->getMachOSection("__TEXT", "__const", 0, 115 SectionKind::getReadOnly()); 116 117 // If the target is not powerpc, map the coal sections to the non-coal 118 // sections. 119 // 120 // "__TEXT/__textcoal_nt" => section "__TEXT/__text" 121 // "__TEXT/__const_coal" => section "__TEXT/__const" 122 // "__DATA/__datacoal_nt" => section "__DATA/__data" 123 Triple::ArchType ArchTy = T.getArch(); 124 125 if (ArchTy == Triple::ppc || ArchTy == Triple::ppc64) { 126 TextCoalSection 127 = Ctx->getMachOSection("__TEXT", "__textcoal_nt", 128 MachO::S_COALESCED | 129 MachO::S_ATTR_PURE_INSTRUCTIONS, 130 SectionKind::getText()); 131 ConstTextCoalSection 132 = Ctx->getMachOSection("__TEXT", "__const_coal", 133 MachO::S_COALESCED, 134 SectionKind::getReadOnly()); 135 DataCoalSection 136 = Ctx->getMachOSection("__DATA","__datacoal_nt", 137 MachO::S_COALESCED, 138 SectionKind::getDataRel()); 139 } else { 140 TextCoalSection = TextSection; 141 ConstTextCoalSection = ReadOnlySection; 142 DataCoalSection = DataSection; 143 } 144 145 ConstDataSection // .const_data 146 = Ctx->getMachOSection("__DATA", "__const", 0, 147 SectionKind::getReadOnlyWithRel()); 148 DataCommonSection 149 = Ctx->getMachOSection("__DATA","__common", 150 MachO::S_ZEROFILL, 151 SectionKind::getBSS()); 152 DataBSSSection 153 = Ctx->getMachOSection("__DATA","__bss", MachO::S_ZEROFILL, 154 SectionKind::getBSS()); 155 156 157 LazySymbolPointerSection 158 = Ctx->getMachOSection("__DATA", "__la_symbol_ptr", 159 MachO::S_LAZY_SYMBOL_POINTERS, 160 SectionKind::getMetadata()); 161 NonLazySymbolPointerSection 162 = Ctx->getMachOSection("__DATA", "__nl_symbol_ptr", 163 MachO::S_NON_LAZY_SYMBOL_POINTERS, 164 SectionKind::getMetadata()); 165 166 if (RelocM == Reloc::Static) { 167 StaticCtorSection 168 = Ctx->getMachOSection("__TEXT", "__constructor", 0, 169 SectionKind::getDataRel()); 170 StaticDtorSection 171 = Ctx->getMachOSection("__TEXT", "__destructor", 0, 172 SectionKind::getDataRel()); 173 } else { 174 StaticCtorSection 175 = Ctx->getMachOSection("__DATA", "__mod_init_func", 176 MachO::S_MOD_INIT_FUNC_POINTERS, 177 SectionKind::getDataRel()); 178 StaticDtorSection 179 = Ctx->getMachOSection("__DATA", "__mod_term_func", 180 MachO::S_MOD_TERM_FUNC_POINTERS, 181 SectionKind::getDataRel()); 182 } 183 184 // Exception Handling. 185 LSDASection = Ctx->getMachOSection("__TEXT", "__gcc_except_tab", 0, 186 SectionKind::getReadOnlyWithRel()); 187 188 COFFDebugSymbolsSection = nullptr; 189 190 if (useCompactUnwind(T)) { 191 CompactUnwindSection = 192 Ctx->getMachOSection("__LD", "__compact_unwind", MachO::S_ATTR_DEBUG, 193 SectionKind::getReadOnly()); 194 195 if (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86) 196 CompactUnwindDwarfEHFrameOnly = 0x04000000; 197 else if (T.getArch() == Triple::aarch64) 198 CompactUnwindDwarfEHFrameOnly = 0x03000000; 199 } 200 201 // Debug Information. 202 DwarfAccelNamesSection = 203 Ctx->getMachOSection("__DWARF", "__apple_names", MachO::S_ATTR_DEBUG, 204 SectionKind::getMetadata(), "names_begin"); 205 DwarfAccelObjCSection = 206 Ctx->getMachOSection("__DWARF", "__apple_objc", MachO::S_ATTR_DEBUG, 207 SectionKind::getMetadata(), "objc_begin"); 208 // 16 character section limit... 209 DwarfAccelNamespaceSection = 210 Ctx->getMachOSection("__DWARF", "__apple_namespac", MachO::S_ATTR_DEBUG, 211 SectionKind::getMetadata(), "namespac_begin"); 212 DwarfAccelTypesSection = 213 Ctx->getMachOSection("__DWARF", "__apple_types", MachO::S_ATTR_DEBUG, 214 SectionKind::getMetadata(), "types_begin"); 215 216 DwarfAbbrevSection = 217 Ctx->getMachOSection("__DWARF", "__debug_abbrev", MachO::S_ATTR_DEBUG, 218 SectionKind::getMetadata(), "section_abbrev"); 219 DwarfInfoSection = 220 Ctx->getMachOSection("__DWARF", "__debug_info", MachO::S_ATTR_DEBUG, 221 SectionKind::getMetadata(), "section_info"); 222 DwarfLineSection = 223 Ctx->getMachOSection("__DWARF", "__debug_line", MachO::S_ATTR_DEBUG, 224 SectionKind::getMetadata(), "section_line"); 225 DwarfFrameSection = 226 Ctx->getMachOSection("__DWARF", "__debug_frame", MachO::S_ATTR_DEBUG, 227 SectionKind::getMetadata()); 228 DwarfPubNamesSection = 229 Ctx->getMachOSection("__DWARF", "__debug_pubnames", MachO::S_ATTR_DEBUG, 230 SectionKind::getMetadata()); 231 DwarfPubTypesSection = 232 Ctx->getMachOSection("__DWARF", "__debug_pubtypes", MachO::S_ATTR_DEBUG, 233 SectionKind::getMetadata()); 234 DwarfGnuPubNamesSection = 235 Ctx->getMachOSection("__DWARF", "__debug_gnu_pubn", MachO::S_ATTR_DEBUG, 236 SectionKind::getMetadata()); 237 DwarfGnuPubTypesSection = 238 Ctx->getMachOSection("__DWARF", "__debug_gnu_pubt", MachO::S_ATTR_DEBUG, 239 SectionKind::getMetadata()); 240 DwarfStrSection = 241 Ctx->getMachOSection("__DWARF", "__debug_str", MachO::S_ATTR_DEBUG, 242 SectionKind::getMetadata(), "info_string"); 243 DwarfLocSection = 244 Ctx->getMachOSection("__DWARF", "__debug_loc", MachO::S_ATTR_DEBUG, 245 SectionKind::getMetadata(), "section_debug_loc"); 246 DwarfARangesSection = 247 Ctx->getMachOSection("__DWARF", "__debug_aranges", MachO::S_ATTR_DEBUG, 248 SectionKind::getMetadata()); 249 DwarfRangesSection = 250 Ctx->getMachOSection("__DWARF", "__debug_ranges", MachO::S_ATTR_DEBUG, 251 SectionKind::getMetadata(), "debug_range"); 252 DwarfDebugInlineSection = 253 Ctx->getMachOSection("__DWARF", "__debug_inlined", MachO::S_ATTR_DEBUG, 254 SectionKind::getMetadata()); 255 StackMapSection = Ctx->getMachOSection("__LLVM_STACKMAPS", "__llvm_stackmaps", 256 0, SectionKind::getMetadata()); 257 258 FaultMapSection = Ctx->getMachOSection("__LLVM_FAULTMAPS", "__llvm_faultmaps", 259 0, SectionKind::getMetadata()); 260 261 TLSExtraDataSection = TLSTLVSection; 262 } 263 264 void MCObjectFileInfo::initELFMCObjectFileInfo(Triple T) { 265 switch (T.getArch()) { 266 case Triple::mips: 267 case Triple::mipsel: 268 FDECFIEncoding = dwarf::DW_EH_PE_sdata4; 269 break; 270 case Triple::mips64: 271 case Triple::mips64el: 272 FDECFIEncoding = dwarf::DW_EH_PE_sdata8; 273 break; 274 case Triple::x86_64: 275 FDECFIEncoding = dwarf::DW_EH_PE_pcrel | 276 ((CMModel == CodeModel::Large) ? dwarf::DW_EH_PE_sdata8 277 : dwarf::DW_EH_PE_sdata4); 278 break; 279 default: 280 FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 281 break; 282 } 283 284 switch (T.getArch()) { 285 case Triple::arm: 286 case Triple::armeb: 287 case Triple::thumb: 288 case Triple::thumbeb: 289 if (Ctx->getAsmInfo()->getExceptionHandlingType() == ExceptionHandling::ARM) 290 break; 291 // Fallthrough if not using EHABI 292 case Triple::ppc: 293 case Triple::x86: 294 PersonalityEncoding = (RelocM == Reloc::PIC_) 295 ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 296 : dwarf::DW_EH_PE_absptr; 297 LSDAEncoding = (RelocM == Reloc::PIC_) 298 ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 299 : dwarf::DW_EH_PE_absptr; 300 TTypeEncoding = (RelocM == Reloc::PIC_) 301 ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 302 : dwarf::DW_EH_PE_absptr; 303 break; 304 case Triple::x86_64: 305 if (RelocM == Reloc::PIC_) { 306 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 307 ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 308 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 309 LSDAEncoding = dwarf::DW_EH_PE_pcrel | 310 (CMModel == CodeModel::Small 311 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 312 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 313 ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 314 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 315 } else { 316 PersonalityEncoding = 317 (CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 318 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 319 LSDAEncoding = (CMModel == CodeModel::Small) 320 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 321 TTypeEncoding = (CMModel == CodeModel::Small) 322 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 323 } 324 break; 325 case Triple::aarch64: 326 case Triple::aarch64_be: 327 // The small model guarantees static code/data size < 4GB, but not where it 328 // will be in memory. Most of these could end up >2GB away so even a signed 329 // pc-relative 32-bit address is insufficient, theoretically. 330 if (RelocM == Reloc::PIC_) { 331 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 332 dwarf::DW_EH_PE_sdata8; 333 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8; 334 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 335 dwarf::DW_EH_PE_sdata8; 336 } else { 337 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 338 LSDAEncoding = dwarf::DW_EH_PE_absptr; 339 TTypeEncoding = dwarf::DW_EH_PE_absptr; 340 } 341 break; 342 case Triple::mips: 343 case Triple::mipsel: 344 case Triple::mips64: 345 case Triple::mips64el: 346 // MIPS uses indirect pointer to refer personality functions and types, so 347 // that the eh_frame section can be read-only. DW.ref.personality will be 348 // generated for relocation. 349 PersonalityEncoding = dwarf::DW_EH_PE_indirect; 350 // FIXME: The N64 ABI probably ought to use DW_EH_PE_sdata8 but we can't 351 // identify N64 from just a triple. 352 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 353 dwarf::DW_EH_PE_sdata4; 354 // We don't support PC-relative LSDA references in GAS so we use the default 355 // DW_EH_PE_absptr for those. 356 break; 357 case Triple::ppc64: 358 case Triple::ppc64le: 359 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 360 dwarf::DW_EH_PE_udata8; 361 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8; 362 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 363 dwarf::DW_EH_PE_udata8; 364 break; 365 case Triple::sparcel: 366 case Triple::sparc: 367 if (RelocM == Reloc::PIC_) { 368 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 369 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 370 dwarf::DW_EH_PE_sdata4; 371 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 372 dwarf::DW_EH_PE_sdata4; 373 } else { 374 LSDAEncoding = dwarf::DW_EH_PE_absptr; 375 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 376 TTypeEncoding = dwarf::DW_EH_PE_absptr; 377 } 378 break; 379 case Triple::sparcv9: 380 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 381 if (RelocM == Reloc::PIC_) { 382 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 383 dwarf::DW_EH_PE_sdata4; 384 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 385 dwarf::DW_EH_PE_sdata4; 386 } else { 387 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 388 TTypeEncoding = dwarf::DW_EH_PE_absptr; 389 } 390 break; 391 case Triple::systemz: 392 // All currently-defined code models guarantee that 4-byte PC-relative 393 // values will be in range. 394 if (RelocM == Reloc::PIC_) { 395 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 396 dwarf::DW_EH_PE_sdata4; 397 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 398 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 399 dwarf::DW_EH_PE_sdata4; 400 } else { 401 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 402 LSDAEncoding = dwarf::DW_EH_PE_absptr; 403 TTypeEncoding = dwarf::DW_EH_PE_absptr; 404 } 405 break; 406 default: 407 break; 408 } 409 410 // Solaris requires different flags for .eh_frame to seemingly every other 411 // platform. 412 EHSectionType = ELF::SHT_PROGBITS; 413 EHSectionFlags = ELF::SHF_ALLOC; 414 if (T.isOSSolaris()) { 415 if (T.getArch() == Triple::x86_64) 416 EHSectionType = ELF::SHT_X86_64_UNWIND; 417 else 418 EHSectionFlags |= ELF::SHF_WRITE; 419 } 420 421 // ELF 422 BSSSection = Ctx->getELFSection(".bss", ELF::SHT_NOBITS, 423 ELF::SHF_WRITE | ELF::SHF_ALLOC); 424 425 TextSection = Ctx->getELFSection(".text", ELF::SHT_PROGBITS, 426 ELF::SHF_EXECINSTR | ELF::SHF_ALLOC); 427 428 DataSection = Ctx->getELFSection(".data", ELF::SHT_PROGBITS, 429 ELF::SHF_WRITE | ELF::SHF_ALLOC); 430 431 ReadOnlySection = 432 Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 433 434 TLSDataSection = 435 Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS, 436 ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE); 437 438 TLSBSSSection = Ctx->getELFSection( 439 ".tbss", ELF::SHT_NOBITS, ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE); 440 441 DataRelSection = Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS, 442 ELF::SHF_ALLOC | ELF::SHF_WRITE); 443 444 DataRelLocalSection = Ctx->getELFSection(".data.rel.local", ELF::SHT_PROGBITS, 445 ELF::SHF_ALLOC | ELF::SHF_WRITE); 446 447 DataRelROSection = Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS, 448 ELF::SHF_ALLOC | ELF::SHF_WRITE); 449 450 DataRelROLocalSection = Ctx->getELFSection( 451 ".data.rel.ro.local", ELF::SHT_PROGBITS, ELF::SHF_ALLOC | ELF::SHF_WRITE); 452 453 MergeableConst4Section = 454 Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS, 455 ELF::SHF_ALLOC | ELF::SHF_MERGE, 4, ""); 456 457 MergeableConst8Section = 458 Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS, 459 ELF::SHF_ALLOC | ELF::SHF_MERGE, 8, ""); 460 461 MergeableConst16Section = 462 Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS, 463 ELF::SHF_ALLOC | ELF::SHF_MERGE, 16, ""); 464 465 StaticCtorSection = Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS, 466 ELF::SHF_ALLOC | ELF::SHF_WRITE); 467 468 StaticDtorSection = Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS, 469 ELF::SHF_ALLOC | ELF::SHF_WRITE); 470 471 // Exception Handling Sections. 472 473 // FIXME: We're emitting LSDA info into a readonly section on ELF, even though 474 // it contains relocatable pointers. In PIC mode, this is probably a big 475 // runtime hit for C++ apps. Either the contents of the LSDA need to be 476 // adjusted or this should be a data section. 477 LSDASection = Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS, 478 ELF::SHF_ALLOC); 479 480 COFFDebugSymbolsSection = nullptr; 481 482 // Debug Info Sections. 483 DwarfAbbrevSection = Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0, 484 "section_abbrev"); 485 DwarfInfoSection = 486 Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0, "section_info"); 487 DwarfLineSection = Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0); 488 DwarfFrameSection = Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0); 489 DwarfPubNamesSection = 490 Ctx->getELFSection(".debug_pubnames", ELF::SHT_PROGBITS, 0); 491 DwarfPubTypesSection = 492 Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0); 493 DwarfGnuPubNamesSection = 494 Ctx->getELFSection(".debug_gnu_pubnames", ELF::SHT_PROGBITS, 0); 495 DwarfGnuPubTypesSection = 496 Ctx->getELFSection(".debug_gnu_pubtypes", ELF::SHT_PROGBITS, 0); 497 DwarfStrSection = 498 Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS, 499 ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, ""); 500 DwarfLocSection = Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0); 501 DwarfARangesSection = 502 Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0); 503 DwarfRangesSection = 504 Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0, "debug_range"); 505 506 // DWARF5 Experimental Debug Info 507 508 // Accelerator Tables 509 DwarfAccelNamesSection = 510 Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0, "names_begin"); 511 DwarfAccelObjCSection = 512 Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0, "objc_begin"); 513 DwarfAccelNamespaceSection = Ctx->getELFSection( 514 ".apple_namespaces", ELF::SHT_PROGBITS, 0, "namespac_begin"); 515 DwarfAccelTypesSection = 516 Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0, "types_begin"); 517 518 // Fission Sections 519 DwarfInfoDWOSection = 520 Ctx->getELFSection(".debug_info.dwo", ELF::SHT_PROGBITS, 0); 521 DwarfTypesDWOSection = 522 Ctx->getELFSection(".debug_types.dwo", ELF::SHT_PROGBITS, 0); 523 DwarfAbbrevDWOSection = 524 Ctx->getELFSection(".debug_abbrev.dwo", ELF::SHT_PROGBITS, 0); 525 DwarfStrDWOSection = 526 Ctx->getELFSection(".debug_str.dwo", ELF::SHT_PROGBITS, 527 ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, ""); 528 DwarfLineDWOSection = 529 Ctx->getELFSection(".debug_line.dwo", ELF::SHT_PROGBITS, 0); 530 DwarfLocDWOSection = 531 Ctx->getELFSection(".debug_loc.dwo", ELF::SHT_PROGBITS, 0, "skel_loc"); 532 DwarfStrOffDWOSection = 533 Ctx->getELFSection(".debug_str_offsets.dwo", ELF::SHT_PROGBITS, 0); 534 DwarfAddrSection = 535 Ctx->getELFSection(".debug_addr", ELF::SHT_PROGBITS, 0, "addr_sec"); 536 537 StackMapSection = 538 Ctx->getELFSection(".llvm_stackmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 539 540 FaultMapSection = 541 Ctx->getELFSection(".llvm_faultmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 542 } 543 544 void MCObjectFileInfo::initCOFFMCObjectFileInfo(Triple T) { 545 bool IsWoA = T.getArch() == Triple::arm || T.getArch() == Triple::thumb; 546 547 CommDirectiveSupportsAlignment = true; 548 549 // COFF 550 BSSSection = Ctx->getCOFFSection( 551 ".bss", COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA | 552 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 553 SectionKind::getBSS()); 554 TextSection = Ctx->getCOFFSection( 555 ".text", 556 (IsWoA ? COFF::IMAGE_SCN_MEM_16BIT : (COFF::SectionCharacteristics)0) | 557 COFF::IMAGE_SCN_CNT_CODE | COFF::IMAGE_SCN_MEM_EXECUTE | 558 COFF::IMAGE_SCN_MEM_READ, 559 SectionKind::getText()); 560 DataSection = Ctx->getCOFFSection( 561 ".data", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ | 562 COFF::IMAGE_SCN_MEM_WRITE, 563 SectionKind::getDataRel()); 564 ReadOnlySection = Ctx->getCOFFSection( 565 ".rdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 566 SectionKind::getReadOnly()); 567 568 if (T.isKnownWindowsMSVCEnvironment() || T.isWindowsItaniumEnvironment()) { 569 StaticCtorSection = 570 Ctx->getCOFFSection(".CRT$XCU", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 571 COFF::IMAGE_SCN_MEM_READ, 572 SectionKind::getReadOnly()); 573 StaticDtorSection = 574 Ctx->getCOFFSection(".CRT$XTX", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 575 COFF::IMAGE_SCN_MEM_READ, 576 SectionKind::getReadOnly()); 577 } else { 578 StaticCtorSection = Ctx->getCOFFSection( 579 ".ctors", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 580 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 581 SectionKind::getDataRel()); 582 StaticDtorSection = Ctx->getCOFFSection( 583 ".dtors", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 584 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 585 SectionKind::getDataRel()); 586 } 587 588 // FIXME: We're emitting LSDA info into a readonly section on COFF, even 589 // though it contains relocatable pointers. In PIC mode, this is probably a 590 // big runtime hit for C++ apps. Either the contents of the LSDA need to be 591 // adjusted or this should be a data section. 592 assert(T.isOSWindows() && "Windows is the only supported COFF target"); 593 if (T.getArch() == Triple::x86_64) { 594 // On Windows 64 with SEH, the LSDA is emitted into the .xdata section 595 LSDASection = nullptr; 596 } else { 597 LSDASection = Ctx->getCOFFSection(".gcc_except_table", 598 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 599 COFF::IMAGE_SCN_MEM_READ, 600 SectionKind::getReadOnly()); 601 } 602 603 // Debug info. 604 COFFDebugSymbolsSection = 605 Ctx->getCOFFSection(".debug$S", COFF::IMAGE_SCN_MEM_DISCARDABLE | 606 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 607 COFF::IMAGE_SCN_MEM_READ, 608 SectionKind::getMetadata()); 609 610 DwarfAbbrevSection = Ctx->getCOFFSection( 611 ".debug_abbrev", 612 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 613 COFF::IMAGE_SCN_MEM_READ, 614 SectionKind::getMetadata(), "section_abbrev"); 615 DwarfInfoSection = Ctx->getCOFFSection( 616 ".debug_info", 617 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 618 COFF::IMAGE_SCN_MEM_READ, 619 SectionKind::getMetadata(), "section_info"); 620 DwarfLineSection = Ctx->getCOFFSection( 621 ".debug_line", 622 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 623 COFF::IMAGE_SCN_MEM_READ, 624 SectionKind::getMetadata(), "section_line"); 625 626 DwarfFrameSection = Ctx->getCOFFSection( 627 ".debug_frame", 628 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 629 COFF::IMAGE_SCN_MEM_READ, 630 SectionKind::getMetadata()); 631 DwarfPubNamesSection = Ctx->getCOFFSection( 632 ".debug_pubnames", 633 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 634 COFF::IMAGE_SCN_MEM_READ, 635 SectionKind::getMetadata()); 636 DwarfPubTypesSection = Ctx->getCOFFSection( 637 ".debug_pubtypes", 638 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 639 COFF::IMAGE_SCN_MEM_READ, 640 SectionKind::getMetadata()); 641 DwarfGnuPubNamesSection = Ctx->getCOFFSection( 642 ".debug_gnu_pubnames", 643 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 644 COFF::IMAGE_SCN_MEM_READ, 645 SectionKind::getMetadata()); 646 DwarfGnuPubTypesSection = Ctx->getCOFFSection( 647 ".debug_gnu_pubtypes", 648 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 649 COFF::IMAGE_SCN_MEM_READ, 650 SectionKind::getMetadata()); 651 DwarfStrSection = Ctx->getCOFFSection( 652 ".debug_str", 653 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 654 COFF::IMAGE_SCN_MEM_READ, 655 SectionKind::getMetadata(), "info_string"); 656 DwarfLocSection = Ctx->getCOFFSection( 657 ".debug_loc", 658 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 659 COFF::IMAGE_SCN_MEM_READ, 660 SectionKind::getMetadata(), "section_debug_loc"); 661 DwarfARangesSection = Ctx->getCOFFSection( 662 ".debug_aranges", 663 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 664 COFF::IMAGE_SCN_MEM_READ, 665 SectionKind::getMetadata()); 666 DwarfRangesSection = Ctx->getCOFFSection( 667 ".debug_ranges", 668 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 669 COFF::IMAGE_SCN_MEM_READ, 670 SectionKind::getMetadata(), "debug_range"); 671 DwarfInfoDWOSection = Ctx->getCOFFSection( 672 ".debug_info.dwo", 673 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 674 COFF::IMAGE_SCN_MEM_READ, 675 SectionKind::getMetadata(), "section_info_dwo"); 676 DwarfTypesDWOSection = Ctx->getCOFFSection( 677 ".debug_types.dwo", 678 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 679 COFF::IMAGE_SCN_MEM_READ, 680 SectionKind::getMetadata(), "section_types_dwo"); 681 DwarfAbbrevDWOSection = Ctx->getCOFFSection( 682 ".debug_abbrev.dwo", 683 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 684 COFF::IMAGE_SCN_MEM_READ, 685 SectionKind::getMetadata(), "section_abbrev_dwo"); 686 DwarfStrDWOSection = Ctx->getCOFFSection( 687 ".debug_str.dwo", 688 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 689 COFF::IMAGE_SCN_MEM_READ, 690 SectionKind::getMetadata(), "skel_string"); 691 DwarfLineDWOSection = Ctx->getCOFFSection( 692 ".debug_line.dwo", 693 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 694 COFF::IMAGE_SCN_MEM_READ, 695 SectionKind::getMetadata()); 696 DwarfLocDWOSection = Ctx->getCOFFSection( 697 ".debug_loc.dwo", 698 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 699 COFF::IMAGE_SCN_MEM_READ, 700 SectionKind::getMetadata(), "skel_loc"); 701 DwarfStrOffDWOSection = Ctx->getCOFFSection( 702 ".debug_str_offsets.dwo", 703 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 704 COFF::IMAGE_SCN_MEM_READ, 705 SectionKind::getMetadata()); 706 DwarfAddrSection = Ctx->getCOFFSection( 707 ".debug_addr", 708 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 709 COFF::IMAGE_SCN_MEM_READ, 710 SectionKind::getMetadata(), "addr_sec"); 711 DwarfAccelNamesSection = Ctx->getCOFFSection( 712 ".apple_names", 713 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 714 COFF::IMAGE_SCN_MEM_READ, 715 SectionKind::getMetadata(), "names_begin"); 716 DwarfAccelNamespaceSection = Ctx->getCOFFSection( 717 ".apple_namespaces", 718 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 719 COFF::IMAGE_SCN_MEM_READ, 720 SectionKind::getMetadata(), "namespac_begin"); 721 DwarfAccelTypesSection = Ctx->getCOFFSection( 722 ".apple_types", 723 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 724 COFF::IMAGE_SCN_MEM_READ, 725 SectionKind::getMetadata(), "types_begin"); 726 DwarfAccelObjCSection = Ctx->getCOFFSection( 727 ".apple_objc", 728 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 729 COFF::IMAGE_SCN_MEM_READ, 730 SectionKind::getMetadata(), "objc_begin"); 731 732 DrectveSection = Ctx->getCOFFSection( 733 ".drectve", COFF::IMAGE_SCN_LNK_INFO | COFF::IMAGE_SCN_LNK_REMOVE, 734 SectionKind::getMetadata()); 735 736 PDataSection = Ctx->getCOFFSection( 737 ".pdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 738 SectionKind::getDataRel()); 739 740 XDataSection = Ctx->getCOFFSection( 741 ".xdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 742 SectionKind::getDataRel()); 743 744 SXDataSection = Ctx->getCOFFSection(".sxdata", COFF::IMAGE_SCN_LNK_INFO, 745 SectionKind::getMetadata()); 746 747 TLSDataSection = Ctx->getCOFFSection( 748 ".tls$", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ | 749 COFF::IMAGE_SCN_MEM_WRITE, 750 SectionKind::getDataRel()); 751 752 StackMapSection = Ctx->getCOFFSection(".llvm_stackmaps", 753 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 754 COFF::IMAGE_SCN_MEM_READ, 755 SectionKind::getReadOnly()); 756 } 757 758 void MCObjectFileInfo::InitMCObjectFileInfo(const Triple &TheTriple, 759 Reloc::Model relocm, 760 CodeModel::Model cm, 761 MCContext &ctx) { 762 RelocM = relocm; 763 CMModel = cm; 764 Ctx = &ctx; 765 766 // Common. 767 CommDirectiveSupportsAlignment = true; 768 SupportsWeakOmittedEHFrame = true; 769 SupportsCompactUnwindWithoutEHFrame = false; 770 771 PersonalityEncoding = LSDAEncoding = FDECFIEncoding = TTypeEncoding = 772 dwarf::DW_EH_PE_absptr; 773 774 CompactUnwindDwarfEHFrameOnly = 0; 775 776 EHFrameSection = nullptr; // Created on demand. 777 CompactUnwindSection = nullptr; // Used only by selected targets. 778 DwarfAccelNamesSection = nullptr; // Used only by selected targets. 779 DwarfAccelObjCSection = nullptr; // Used only by selected targets. 780 DwarfAccelNamespaceSection = nullptr; // Used only by selected targets. 781 DwarfAccelTypesSection = nullptr; // Used only by selected targets. 782 783 TT = TheTriple; 784 785 Triple::ArchType Arch = TT.getArch(); 786 // FIXME: Checking for Arch here to filter out bogus triples such as 787 // cellspu-apple-darwin. Perhaps we should fix in Triple? 788 if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 789 Arch == Triple::arm || Arch == Triple::thumb || 790 Arch == Triple::aarch64 || 791 Arch == Triple::ppc || Arch == Triple::ppc64 || 792 Arch == Triple::UnknownArch) && 793 TT.isOSBinFormatMachO()) { 794 Env = IsMachO; 795 initMachOMCObjectFileInfo(TT); 796 } else if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 797 Arch == Triple::arm || Arch == Triple::thumb) && 798 (TT.isOSWindows() && TT.getObjectFormat() == Triple::COFF)) { 799 Env = IsCOFF; 800 initCOFFMCObjectFileInfo(TT); 801 } else { 802 Env = IsELF; 803 initELFMCObjectFileInfo(TT); 804 } 805 } 806 807 void MCObjectFileInfo::InitMCObjectFileInfo(StringRef TT, Reloc::Model RM, 808 CodeModel::Model CM, 809 MCContext &ctx) { 810 InitMCObjectFileInfo(Triple(TT), RM, CM, ctx); 811 } 812 813 MCSection *MCObjectFileInfo::getDwarfTypesSection(uint64_t Hash) const { 814 return Ctx->getELFSection(".debug_types", ELF::SHT_PROGBITS, ELF::SHF_GROUP, 815 0, utostr(Hash)); 816 } 817 818 void MCObjectFileInfo::InitEHFrameSection() { 819 if (Env == IsMachO) 820 EHFrameSection = 821 Ctx->getMachOSection("__TEXT", "__eh_frame", 822 MachO::S_COALESCED | 823 MachO::S_ATTR_NO_TOC | 824 MachO::S_ATTR_STRIP_STATIC_SYMS | 825 MachO::S_ATTR_LIVE_SUPPORT, 826 SectionKind::getReadOnly()); 827 else if (Env == IsELF) 828 EHFrameSection = 829 Ctx->getELFSection(".eh_frame", EHSectionType, EHSectionFlags); 830 else 831 EHFrameSection = 832 Ctx->getCOFFSection(".eh_frame", 833 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 834 COFF::IMAGE_SCN_MEM_READ | 835 COFF::IMAGE_SCN_MEM_WRITE, 836 SectionKind::getDataRel()); 837 } 838