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 // armv7k always has it. 33 if (T.isWatchOS()) 34 return true; 35 36 // Use it on newer version of OS X. 37 if (T.isMacOSX() && !T.isMacOSXVersionLT(10, 6)) 38 return true; 39 40 // And the iOS simulator. 41 if (T.isiOS() && 42 (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86)) 43 return true; 44 45 return false; 46 } 47 48 void MCObjectFileInfo::initMachOMCObjectFileInfo(Triple T) { 49 // MachO 50 SupportsWeakOmittedEHFrame = false; 51 52 EHFrameSection = Ctx->getMachOSection( 53 "__TEXT", "__eh_frame", 54 MachO::S_COALESCED | MachO::S_ATTR_NO_TOC | 55 MachO::S_ATTR_STRIP_STATIC_SYMS | MachO::S_ATTR_LIVE_SUPPORT, 56 SectionKind::getReadOnly()); 57 58 if (T.isOSDarwin() && T.getArch() == Triple::aarch64) 59 SupportsCompactUnwindWithoutEHFrame = true; 60 61 if (T.isWatchOS()) 62 OmitDwarfIfHaveCompactUnwind = true; 63 64 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel 65 | dwarf::DW_EH_PE_sdata4; 66 LSDAEncoding = FDECFIEncoding = dwarf::DW_EH_PE_pcrel; 67 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 68 dwarf::DW_EH_PE_sdata4; 69 70 // .comm doesn't support alignment before Leopard. 71 if (T.isMacOSX() && T.isMacOSXVersionLT(10, 5)) 72 CommDirectiveSupportsAlignment = false; 73 74 TextSection // .text 75 = Ctx->getMachOSection("__TEXT", "__text", 76 MachO::S_ATTR_PURE_INSTRUCTIONS, 77 SectionKind::getText()); 78 DataSection // .data 79 = Ctx->getMachOSection("__DATA", "__data", 0, 80 SectionKind::getDataRel()); 81 82 // BSSSection might not be expected initialized on msvc. 83 BSSSection = nullptr; 84 85 TLSDataSection // .tdata 86 = Ctx->getMachOSection("__DATA", "__thread_data", 87 MachO::S_THREAD_LOCAL_REGULAR, 88 SectionKind::getDataRel()); 89 TLSBSSSection // .tbss 90 = Ctx->getMachOSection("__DATA", "__thread_bss", 91 MachO::S_THREAD_LOCAL_ZEROFILL, 92 SectionKind::getThreadBSS()); 93 94 // TODO: Verify datarel below. 95 TLSTLVSection // .tlv 96 = Ctx->getMachOSection("__DATA", "__thread_vars", 97 MachO::S_THREAD_LOCAL_VARIABLES, 98 SectionKind::getDataRel()); 99 100 TLSThreadInitSection 101 = Ctx->getMachOSection("__DATA", "__thread_init", 102 MachO::S_THREAD_LOCAL_INIT_FUNCTION_POINTERS, 103 SectionKind::getDataRel()); 104 105 CStringSection // .cstring 106 = Ctx->getMachOSection("__TEXT", "__cstring", 107 MachO::S_CSTRING_LITERALS, 108 SectionKind::getMergeable1ByteCString()); 109 UStringSection 110 = Ctx->getMachOSection("__TEXT","__ustring", 0, 111 SectionKind::getMergeable2ByteCString()); 112 FourByteConstantSection // .literal4 113 = Ctx->getMachOSection("__TEXT", "__literal4", 114 MachO::S_4BYTE_LITERALS, 115 SectionKind::getMergeableConst4()); 116 EightByteConstantSection // .literal8 117 = Ctx->getMachOSection("__TEXT", "__literal8", 118 MachO::S_8BYTE_LITERALS, 119 SectionKind::getMergeableConst8()); 120 121 SixteenByteConstantSection // .literal16 122 = Ctx->getMachOSection("__TEXT", "__literal16", 123 MachO::S_16BYTE_LITERALS, 124 SectionKind::getMergeableConst16()); 125 126 ReadOnlySection // .const 127 = Ctx->getMachOSection("__TEXT", "__const", 0, 128 SectionKind::getReadOnly()); 129 130 // If the target is not powerpc, map the coal sections to the non-coal 131 // sections. 132 // 133 // "__TEXT/__textcoal_nt" => section "__TEXT/__text" 134 // "__TEXT/__const_coal" => section "__TEXT/__const" 135 // "__DATA/__datacoal_nt" => section "__DATA/__data" 136 Triple::ArchType ArchTy = T.getArch(); 137 138 if (ArchTy == Triple::ppc || ArchTy == Triple::ppc64) { 139 TextCoalSection 140 = Ctx->getMachOSection("__TEXT", "__textcoal_nt", 141 MachO::S_COALESCED | 142 MachO::S_ATTR_PURE_INSTRUCTIONS, 143 SectionKind::getText()); 144 ConstTextCoalSection 145 = Ctx->getMachOSection("__TEXT", "__const_coal", 146 MachO::S_COALESCED, 147 SectionKind::getReadOnly()); 148 DataCoalSection 149 = Ctx->getMachOSection("__DATA","__datacoal_nt", 150 MachO::S_COALESCED, 151 SectionKind::getDataRel()); 152 } else { 153 TextCoalSection = TextSection; 154 ConstTextCoalSection = ReadOnlySection; 155 DataCoalSection = DataSection; 156 } 157 158 ConstDataSection // .const_data 159 = Ctx->getMachOSection("__DATA", "__const", 0, 160 SectionKind::getReadOnlyWithRel()); 161 DataCommonSection 162 = Ctx->getMachOSection("__DATA","__common", 163 MachO::S_ZEROFILL, 164 SectionKind::getBSS()); 165 DataBSSSection 166 = Ctx->getMachOSection("__DATA","__bss", MachO::S_ZEROFILL, 167 SectionKind::getBSS()); 168 169 170 LazySymbolPointerSection 171 = Ctx->getMachOSection("__DATA", "__la_symbol_ptr", 172 MachO::S_LAZY_SYMBOL_POINTERS, 173 SectionKind::getMetadata()); 174 NonLazySymbolPointerSection 175 = Ctx->getMachOSection("__DATA", "__nl_symbol_ptr", 176 MachO::S_NON_LAZY_SYMBOL_POINTERS, 177 SectionKind::getMetadata()); 178 179 if (RelocM == Reloc::Static) { 180 StaticCtorSection 181 = Ctx->getMachOSection("__TEXT", "__constructor", 0, 182 SectionKind::getDataRel()); 183 StaticDtorSection 184 = Ctx->getMachOSection("__TEXT", "__destructor", 0, 185 SectionKind::getDataRel()); 186 } else { 187 StaticCtorSection 188 = Ctx->getMachOSection("__DATA", "__mod_init_func", 189 MachO::S_MOD_INIT_FUNC_POINTERS, 190 SectionKind::getDataRel()); 191 StaticDtorSection 192 = Ctx->getMachOSection("__DATA", "__mod_term_func", 193 MachO::S_MOD_TERM_FUNC_POINTERS, 194 SectionKind::getDataRel()); 195 } 196 197 // Exception Handling. 198 LSDASection = Ctx->getMachOSection("__TEXT", "__gcc_except_tab", 0, 199 SectionKind::getReadOnlyWithRel()); 200 201 COFFDebugSymbolsSection = nullptr; 202 203 if (useCompactUnwind(T)) { 204 CompactUnwindSection = 205 Ctx->getMachOSection("__LD", "__compact_unwind", MachO::S_ATTR_DEBUG, 206 SectionKind::getReadOnly()); 207 208 if (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86) 209 CompactUnwindDwarfEHFrameOnly = 0x04000000; // UNWIND_X86_64_MODE_DWARF 210 else if (T.getArch() == Triple::aarch64) 211 CompactUnwindDwarfEHFrameOnly = 0x03000000; // UNWIND_ARM64_MODE_DWARF 212 else if (T.getArch() == Triple::arm || T.getArch() == Triple::thumb) 213 CompactUnwindDwarfEHFrameOnly = 0x04000000; // UNWIND_ARM_MODE_DWARF 214 } 215 216 // Debug Information. 217 DwarfAccelNamesSection = 218 Ctx->getMachOSection("__DWARF", "__apple_names", MachO::S_ATTR_DEBUG, 219 SectionKind::getMetadata(), "names_begin"); 220 DwarfAccelObjCSection = 221 Ctx->getMachOSection("__DWARF", "__apple_objc", MachO::S_ATTR_DEBUG, 222 SectionKind::getMetadata(), "objc_begin"); 223 // 16 character section limit... 224 DwarfAccelNamespaceSection = 225 Ctx->getMachOSection("__DWARF", "__apple_namespac", MachO::S_ATTR_DEBUG, 226 SectionKind::getMetadata(), "namespac_begin"); 227 DwarfAccelTypesSection = 228 Ctx->getMachOSection("__DWARF", "__apple_types", MachO::S_ATTR_DEBUG, 229 SectionKind::getMetadata(), "types_begin"); 230 231 DwarfAbbrevSection = 232 Ctx->getMachOSection("__DWARF", "__debug_abbrev", MachO::S_ATTR_DEBUG, 233 SectionKind::getMetadata(), "section_abbrev"); 234 DwarfInfoSection = 235 Ctx->getMachOSection("__DWARF", "__debug_info", MachO::S_ATTR_DEBUG, 236 SectionKind::getMetadata(), "section_info"); 237 DwarfLineSection = 238 Ctx->getMachOSection("__DWARF", "__debug_line", MachO::S_ATTR_DEBUG, 239 SectionKind::getMetadata(), "section_line"); 240 DwarfFrameSection = 241 Ctx->getMachOSection("__DWARF", "__debug_frame", MachO::S_ATTR_DEBUG, 242 SectionKind::getMetadata()); 243 DwarfPubNamesSection = 244 Ctx->getMachOSection("__DWARF", "__debug_pubnames", MachO::S_ATTR_DEBUG, 245 SectionKind::getMetadata()); 246 DwarfPubTypesSection = 247 Ctx->getMachOSection("__DWARF", "__debug_pubtypes", MachO::S_ATTR_DEBUG, 248 SectionKind::getMetadata()); 249 DwarfGnuPubNamesSection = 250 Ctx->getMachOSection("__DWARF", "__debug_gnu_pubn", MachO::S_ATTR_DEBUG, 251 SectionKind::getMetadata()); 252 DwarfGnuPubTypesSection = 253 Ctx->getMachOSection("__DWARF", "__debug_gnu_pubt", MachO::S_ATTR_DEBUG, 254 SectionKind::getMetadata()); 255 DwarfStrSection = 256 Ctx->getMachOSection("__DWARF", "__debug_str", MachO::S_ATTR_DEBUG, 257 SectionKind::getMetadata(), "info_string"); 258 DwarfLocSection = 259 Ctx->getMachOSection("__DWARF", "__debug_loc", MachO::S_ATTR_DEBUG, 260 SectionKind::getMetadata(), "section_debug_loc"); 261 DwarfARangesSection = 262 Ctx->getMachOSection("__DWARF", "__debug_aranges", MachO::S_ATTR_DEBUG, 263 SectionKind::getMetadata()); 264 DwarfRangesSection = 265 Ctx->getMachOSection("__DWARF", "__debug_ranges", MachO::S_ATTR_DEBUG, 266 SectionKind::getMetadata(), "debug_range"); 267 DwarfDebugInlineSection = 268 Ctx->getMachOSection("__DWARF", "__debug_inlined", MachO::S_ATTR_DEBUG, 269 SectionKind::getMetadata()); 270 StackMapSection = Ctx->getMachOSection("__LLVM_STACKMAPS", "__llvm_stackmaps", 271 0, SectionKind::getMetadata()); 272 273 FaultMapSection = Ctx->getMachOSection("__LLVM_FAULTMAPS", "__llvm_faultmaps", 274 0, SectionKind::getMetadata()); 275 276 TLSExtraDataSection = TLSTLVSection; 277 } 278 279 void MCObjectFileInfo::initELFMCObjectFileInfo(Triple T) { 280 switch (T.getArch()) { 281 case Triple::mips: 282 case Triple::mipsel: 283 FDECFIEncoding = dwarf::DW_EH_PE_sdata4; 284 break; 285 case Triple::mips64: 286 case Triple::mips64el: 287 FDECFIEncoding = dwarf::DW_EH_PE_sdata8; 288 break; 289 case Triple::x86_64: 290 FDECFIEncoding = dwarf::DW_EH_PE_pcrel | 291 ((CMModel == CodeModel::Large) ? dwarf::DW_EH_PE_sdata8 292 : dwarf::DW_EH_PE_sdata4); 293 break; 294 default: 295 FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 296 break; 297 } 298 299 switch (T.getArch()) { 300 case Triple::arm: 301 case Triple::armeb: 302 case Triple::thumb: 303 case Triple::thumbeb: 304 if (Ctx->getAsmInfo()->getExceptionHandlingType() == ExceptionHandling::ARM) 305 break; 306 // Fallthrough if not using EHABI 307 case Triple::ppc: 308 case Triple::x86: 309 PersonalityEncoding = (RelocM == Reloc::PIC_) 310 ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 311 : dwarf::DW_EH_PE_absptr; 312 LSDAEncoding = (RelocM == Reloc::PIC_) 313 ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 314 : dwarf::DW_EH_PE_absptr; 315 TTypeEncoding = (RelocM == Reloc::PIC_) 316 ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 317 : dwarf::DW_EH_PE_absptr; 318 break; 319 case Triple::x86_64: 320 if (RelocM == Reloc::PIC_) { 321 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 322 ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 323 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 324 LSDAEncoding = dwarf::DW_EH_PE_pcrel | 325 (CMModel == CodeModel::Small 326 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 327 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 328 ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 329 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 330 } else { 331 PersonalityEncoding = 332 (CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 333 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 334 LSDAEncoding = (CMModel == CodeModel::Small) 335 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 336 TTypeEncoding = (CMModel == CodeModel::Small) 337 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 338 } 339 break; 340 case Triple::aarch64: 341 case Triple::aarch64_be: 342 // The small model guarantees static code/data size < 4GB, but not where it 343 // will be in memory. Most of these could end up >2GB away so even a signed 344 // pc-relative 32-bit address is insufficient, theoretically. 345 if (RelocM == Reloc::PIC_) { 346 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 347 dwarf::DW_EH_PE_sdata8; 348 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8; 349 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 350 dwarf::DW_EH_PE_sdata8; 351 } else { 352 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 353 LSDAEncoding = dwarf::DW_EH_PE_absptr; 354 TTypeEncoding = dwarf::DW_EH_PE_absptr; 355 } 356 break; 357 case Triple::mips: 358 case Triple::mipsel: 359 case Triple::mips64: 360 case Triple::mips64el: 361 // MIPS uses indirect pointer to refer personality functions and types, so 362 // that the eh_frame section can be read-only. DW.ref.personality will be 363 // generated for relocation. 364 PersonalityEncoding = dwarf::DW_EH_PE_indirect; 365 // FIXME: The N64 ABI probably ought to use DW_EH_PE_sdata8 but we can't 366 // identify N64 from just a triple. 367 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 368 dwarf::DW_EH_PE_sdata4; 369 // We don't support PC-relative LSDA references in GAS so we use the default 370 // DW_EH_PE_absptr for those. 371 break; 372 case Triple::ppc64: 373 case Triple::ppc64le: 374 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 375 dwarf::DW_EH_PE_udata8; 376 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8; 377 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 378 dwarf::DW_EH_PE_udata8; 379 break; 380 case Triple::sparcel: 381 case Triple::sparc: 382 if (RelocM == Reloc::PIC_) { 383 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 384 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 385 dwarf::DW_EH_PE_sdata4; 386 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 387 dwarf::DW_EH_PE_sdata4; 388 } else { 389 LSDAEncoding = dwarf::DW_EH_PE_absptr; 390 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 391 TTypeEncoding = dwarf::DW_EH_PE_absptr; 392 } 393 break; 394 case Triple::sparcv9: 395 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 396 if (RelocM == Reloc::PIC_) { 397 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 398 dwarf::DW_EH_PE_sdata4; 399 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 400 dwarf::DW_EH_PE_sdata4; 401 } else { 402 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 403 TTypeEncoding = dwarf::DW_EH_PE_absptr; 404 } 405 break; 406 case Triple::systemz: 407 // All currently-defined code models guarantee that 4-byte PC-relative 408 // values will be in range. 409 if (RelocM == Reloc::PIC_) { 410 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 411 dwarf::DW_EH_PE_sdata4; 412 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 413 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 414 dwarf::DW_EH_PE_sdata4; 415 } else { 416 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 417 LSDAEncoding = dwarf::DW_EH_PE_absptr; 418 TTypeEncoding = dwarf::DW_EH_PE_absptr; 419 } 420 break; 421 default: 422 break; 423 } 424 425 unsigned EHSectionType = T.getArch() == Triple::x86_64 426 ? ELF::SHT_X86_64_UNWIND 427 : ELF::SHT_PROGBITS; 428 429 // Solaris requires different flags for .eh_frame to seemingly every other 430 // platform. 431 unsigned EHSectionFlags = ELF::SHF_ALLOC; 432 if (T.isOSSolaris() && T.getArch() != Triple::x86_64) 433 EHSectionFlags |= ELF::SHF_WRITE; 434 435 // ELF 436 BSSSection = Ctx->getELFSection(".bss", ELF::SHT_NOBITS, 437 ELF::SHF_WRITE | ELF::SHF_ALLOC); 438 439 TextSection = Ctx->getELFSection(".text", ELF::SHT_PROGBITS, 440 ELF::SHF_EXECINSTR | ELF::SHF_ALLOC); 441 442 DataSection = Ctx->getELFSection(".data", ELF::SHT_PROGBITS, 443 ELF::SHF_WRITE | ELF::SHF_ALLOC); 444 445 ReadOnlySection = 446 Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 447 448 TLSDataSection = 449 Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS, 450 ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE); 451 452 TLSBSSSection = Ctx->getELFSection( 453 ".tbss", ELF::SHT_NOBITS, ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE); 454 455 DataRelSection = Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS, 456 ELF::SHF_ALLOC | ELF::SHF_WRITE); 457 458 DataRelROSection = Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS, 459 ELF::SHF_ALLOC | ELF::SHF_WRITE); 460 461 MergeableConst4Section = 462 Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS, 463 ELF::SHF_ALLOC | ELF::SHF_MERGE, 4, ""); 464 465 MergeableConst8Section = 466 Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS, 467 ELF::SHF_ALLOC | ELF::SHF_MERGE, 8, ""); 468 469 MergeableConst16Section = 470 Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS, 471 ELF::SHF_ALLOC | ELF::SHF_MERGE, 16, ""); 472 473 StaticCtorSection = Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS, 474 ELF::SHF_ALLOC | ELF::SHF_WRITE); 475 476 StaticDtorSection = Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS, 477 ELF::SHF_ALLOC | ELF::SHF_WRITE); 478 479 // Exception Handling Sections. 480 481 // FIXME: We're emitting LSDA info into a readonly section on ELF, even though 482 // it contains relocatable pointers. In PIC mode, this is probably a big 483 // runtime hit for C++ apps. Either the contents of the LSDA need to be 484 // adjusted or this should be a data section. 485 LSDASection = Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS, 486 ELF::SHF_ALLOC); 487 488 COFFDebugSymbolsSection = nullptr; 489 490 // Debug Info Sections. 491 DwarfAbbrevSection = Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0, 492 "section_abbrev"); 493 DwarfInfoSection = 494 Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0, "section_info"); 495 DwarfLineSection = Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0); 496 DwarfFrameSection = Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0); 497 DwarfPubNamesSection = 498 Ctx->getELFSection(".debug_pubnames", ELF::SHT_PROGBITS, 0); 499 DwarfPubTypesSection = 500 Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0); 501 DwarfGnuPubNamesSection = 502 Ctx->getELFSection(".debug_gnu_pubnames", ELF::SHT_PROGBITS, 0); 503 DwarfGnuPubTypesSection = 504 Ctx->getELFSection(".debug_gnu_pubtypes", ELF::SHT_PROGBITS, 0); 505 DwarfStrSection = 506 Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS, 507 ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, ""); 508 DwarfLocSection = Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0); 509 DwarfARangesSection = 510 Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0); 511 DwarfRangesSection = 512 Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0, "debug_range"); 513 514 // DWARF5 Experimental Debug Info 515 516 // Accelerator Tables 517 DwarfAccelNamesSection = 518 Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0, "names_begin"); 519 DwarfAccelObjCSection = 520 Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0, "objc_begin"); 521 DwarfAccelNamespaceSection = Ctx->getELFSection( 522 ".apple_namespaces", ELF::SHT_PROGBITS, 0, "namespac_begin"); 523 DwarfAccelTypesSection = 524 Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0, "types_begin"); 525 526 // Fission Sections 527 DwarfInfoDWOSection = 528 Ctx->getELFSection(".debug_info.dwo", ELF::SHT_PROGBITS, 0); 529 DwarfTypesDWOSection = 530 Ctx->getELFSection(".debug_types.dwo", ELF::SHT_PROGBITS, 0); 531 DwarfAbbrevDWOSection = 532 Ctx->getELFSection(".debug_abbrev.dwo", ELF::SHT_PROGBITS, 0); 533 DwarfStrDWOSection = 534 Ctx->getELFSection(".debug_str.dwo", ELF::SHT_PROGBITS, 535 ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, ""); 536 DwarfLineDWOSection = 537 Ctx->getELFSection(".debug_line.dwo", ELF::SHT_PROGBITS, 0); 538 DwarfLocDWOSection = 539 Ctx->getELFSection(".debug_loc.dwo", ELF::SHT_PROGBITS, 0, "skel_loc"); 540 DwarfStrOffDWOSection = 541 Ctx->getELFSection(".debug_str_offsets.dwo", ELF::SHT_PROGBITS, 0); 542 DwarfAddrSection = 543 Ctx->getELFSection(".debug_addr", ELF::SHT_PROGBITS, 0, "addr_sec"); 544 545 StackMapSection = 546 Ctx->getELFSection(".llvm_stackmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 547 548 FaultMapSection = 549 Ctx->getELFSection(".llvm_faultmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 550 551 EHFrameSection = 552 Ctx->getELFSection(".eh_frame", EHSectionType, EHSectionFlags); 553 } 554 555 void MCObjectFileInfo::initCOFFMCObjectFileInfo(Triple T) { 556 EHFrameSection = Ctx->getCOFFSection( 557 ".eh_frame", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 558 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 559 SectionKind::getDataRel()); 560 561 bool IsWoA = T.getArch() == Triple::arm || T.getArch() == Triple::thumb; 562 563 CommDirectiveSupportsAlignment = true; 564 565 // COFF 566 BSSSection = Ctx->getCOFFSection( 567 ".bss", COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA | 568 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 569 SectionKind::getBSS()); 570 TextSection = Ctx->getCOFFSection( 571 ".text", 572 (IsWoA ? COFF::IMAGE_SCN_MEM_16BIT : (COFF::SectionCharacteristics)0) | 573 COFF::IMAGE_SCN_CNT_CODE | COFF::IMAGE_SCN_MEM_EXECUTE | 574 COFF::IMAGE_SCN_MEM_READ, 575 SectionKind::getText()); 576 DataSection = Ctx->getCOFFSection( 577 ".data", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ | 578 COFF::IMAGE_SCN_MEM_WRITE, 579 SectionKind::getDataRel()); 580 ReadOnlySection = Ctx->getCOFFSection( 581 ".rdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 582 SectionKind::getReadOnly()); 583 584 if (T.isKnownWindowsMSVCEnvironment() || T.isWindowsItaniumEnvironment()) { 585 StaticCtorSection = 586 Ctx->getCOFFSection(".CRT$XCU", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 587 COFF::IMAGE_SCN_MEM_READ, 588 SectionKind::getReadOnly()); 589 StaticDtorSection = 590 Ctx->getCOFFSection(".CRT$XTX", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 591 COFF::IMAGE_SCN_MEM_READ, 592 SectionKind::getReadOnly()); 593 } else { 594 StaticCtorSection = Ctx->getCOFFSection( 595 ".ctors", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 596 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 597 SectionKind::getDataRel()); 598 StaticDtorSection = Ctx->getCOFFSection( 599 ".dtors", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 600 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 601 SectionKind::getDataRel()); 602 } 603 604 // FIXME: We're emitting LSDA info into a readonly section on COFF, even 605 // though it contains relocatable pointers. In PIC mode, this is probably a 606 // big runtime hit for C++ apps. Either the contents of the LSDA need to be 607 // adjusted or this should be a data section. 608 assert(T.isOSWindows() && "Windows is the only supported COFF target"); 609 if (T.getArch() == Triple::x86_64) { 610 // On Windows 64 with SEH, the LSDA is emitted into the .xdata section 611 LSDASection = nullptr; 612 } else { 613 LSDASection = Ctx->getCOFFSection(".gcc_except_table", 614 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 615 COFF::IMAGE_SCN_MEM_READ, 616 SectionKind::getReadOnly()); 617 } 618 619 // Debug info. 620 COFFDebugSymbolsSection = 621 Ctx->getCOFFSection(".debug$S", COFF::IMAGE_SCN_MEM_DISCARDABLE | 622 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 623 COFF::IMAGE_SCN_MEM_READ, 624 SectionKind::getMetadata()); 625 626 DwarfAbbrevSection = Ctx->getCOFFSection( 627 ".debug_abbrev", 628 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 629 COFF::IMAGE_SCN_MEM_READ, 630 SectionKind::getMetadata(), "section_abbrev"); 631 DwarfInfoSection = Ctx->getCOFFSection( 632 ".debug_info", 633 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 634 COFF::IMAGE_SCN_MEM_READ, 635 SectionKind::getMetadata(), "section_info"); 636 DwarfLineSection = Ctx->getCOFFSection( 637 ".debug_line", 638 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 639 COFF::IMAGE_SCN_MEM_READ, 640 SectionKind::getMetadata(), "section_line"); 641 642 DwarfFrameSection = Ctx->getCOFFSection( 643 ".debug_frame", 644 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 645 COFF::IMAGE_SCN_MEM_READ, 646 SectionKind::getMetadata()); 647 DwarfPubNamesSection = Ctx->getCOFFSection( 648 ".debug_pubnames", 649 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 650 COFF::IMAGE_SCN_MEM_READ, 651 SectionKind::getMetadata()); 652 DwarfPubTypesSection = Ctx->getCOFFSection( 653 ".debug_pubtypes", 654 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 655 COFF::IMAGE_SCN_MEM_READ, 656 SectionKind::getMetadata()); 657 DwarfGnuPubNamesSection = Ctx->getCOFFSection( 658 ".debug_gnu_pubnames", 659 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 660 COFF::IMAGE_SCN_MEM_READ, 661 SectionKind::getMetadata()); 662 DwarfGnuPubTypesSection = Ctx->getCOFFSection( 663 ".debug_gnu_pubtypes", 664 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 665 COFF::IMAGE_SCN_MEM_READ, 666 SectionKind::getMetadata()); 667 DwarfStrSection = Ctx->getCOFFSection( 668 ".debug_str", 669 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 670 COFF::IMAGE_SCN_MEM_READ, 671 SectionKind::getMetadata(), "info_string"); 672 DwarfLocSection = Ctx->getCOFFSection( 673 ".debug_loc", 674 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 675 COFF::IMAGE_SCN_MEM_READ, 676 SectionKind::getMetadata(), "section_debug_loc"); 677 DwarfARangesSection = Ctx->getCOFFSection( 678 ".debug_aranges", 679 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 680 COFF::IMAGE_SCN_MEM_READ, 681 SectionKind::getMetadata()); 682 DwarfRangesSection = Ctx->getCOFFSection( 683 ".debug_ranges", 684 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 685 COFF::IMAGE_SCN_MEM_READ, 686 SectionKind::getMetadata(), "debug_range"); 687 DwarfInfoDWOSection = Ctx->getCOFFSection( 688 ".debug_info.dwo", 689 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 690 COFF::IMAGE_SCN_MEM_READ, 691 SectionKind::getMetadata(), "section_info_dwo"); 692 DwarfTypesDWOSection = Ctx->getCOFFSection( 693 ".debug_types.dwo", 694 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 695 COFF::IMAGE_SCN_MEM_READ, 696 SectionKind::getMetadata(), "section_types_dwo"); 697 DwarfAbbrevDWOSection = Ctx->getCOFFSection( 698 ".debug_abbrev.dwo", 699 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 700 COFF::IMAGE_SCN_MEM_READ, 701 SectionKind::getMetadata(), "section_abbrev_dwo"); 702 DwarfStrDWOSection = Ctx->getCOFFSection( 703 ".debug_str.dwo", 704 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 705 COFF::IMAGE_SCN_MEM_READ, 706 SectionKind::getMetadata(), "skel_string"); 707 DwarfLineDWOSection = Ctx->getCOFFSection( 708 ".debug_line.dwo", 709 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 710 COFF::IMAGE_SCN_MEM_READ, 711 SectionKind::getMetadata()); 712 DwarfLocDWOSection = Ctx->getCOFFSection( 713 ".debug_loc.dwo", 714 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 715 COFF::IMAGE_SCN_MEM_READ, 716 SectionKind::getMetadata(), "skel_loc"); 717 DwarfStrOffDWOSection = Ctx->getCOFFSection( 718 ".debug_str_offsets.dwo", 719 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 720 COFF::IMAGE_SCN_MEM_READ, 721 SectionKind::getMetadata()); 722 DwarfAddrSection = Ctx->getCOFFSection( 723 ".debug_addr", 724 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 725 COFF::IMAGE_SCN_MEM_READ, 726 SectionKind::getMetadata(), "addr_sec"); 727 DwarfAccelNamesSection = Ctx->getCOFFSection( 728 ".apple_names", 729 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 730 COFF::IMAGE_SCN_MEM_READ, 731 SectionKind::getMetadata(), "names_begin"); 732 DwarfAccelNamespaceSection = Ctx->getCOFFSection( 733 ".apple_namespaces", 734 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 735 COFF::IMAGE_SCN_MEM_READ, 736 SectionKind::getMetadata(), "namespac_begin"); 737 DwarfAccelTypesSection = Ctx->getCOFFSection( 738 ".apple_types", 739 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 740 COFF::IMAGE_SCN_MEM_READ, 741 SectionKind::getMetadata(), "types_begin"); 742 DwarfAccelObjCSection = Ctx->getCOFFSection( 743 ".apple_objc", 744 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 745 COFF::IMAGE_SCN_MEM_READ, 746 SectionKind::getMetadata(), "objc_begin"); 747 748 DrectveSection = Ctx->getCOFFSection( 749 ".drectve", COFF::IMAGE_SCN_LNK_INFO | COFF::IMAGE_SCN_LNK_REMOVE, 750 SectionKind::getMetadata()); 751 752 PDataSection = Ctx->getCOFFSection( 753 ".pdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 754 SectionKind::getDataRel()); 755 756 XDataSection = Ctx->getCOFFSection( 757 ".xdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 758 SectionKind::getDataRel()); 759 760 SXDataSection = Ctx->getCOFFSection(".sxdata", COFF::IMAGE_SCN_LNK_INFO, 761 SectionKind::getMetadata()); 762 763 TLSDataSection = Ctx->getCOFFSection( 764 ".tls$", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ | 765 COFF::IMAGE_SCN_MEM_WRITE, 766 SectionKind::getDataRel()); 767 768 StackMapSection = Ctx->getCOFFSection(".llvm_stackmaps", 769 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 770 COFF::IMAGE_SCN_MEM_READ, 771 SectionKind::getReadOnly()); 772 } 773 774 void MCObjectFileInfo::InitMCObjectFileInfo(const Triple &TheTriple, 775 Reloc::Model relocm, 776 CodeModel::Model cm, 777 MCContext &ctx) { 778 RelocM = relocm; 779 CMModel = cm; 780 Ctx = &ctx; 781 782 // Common. 783 CommDirectiveSupportsAlignment = true; 784 SupportsWeakOmittedEHFrame = true; 785 SupportsCompactUnwindWithoutEHFrame = false; 786 OmitDwarfIfHaveCompactUnwind = false; 787 788 PersonalityEncoding = LSDAEncoding = FDECFIEncoding = TTypeEncoding = 789 dwarf::DW_EH_PE_absptr; 790 791 CompactUnwindDwarfEHFrameOnly = 0; 792 793 EHFrameSection = nullptr; // Created on demand. 794 CompactUnwindSection = nullptr; // Used only by selected targets. 795 DwarfAccelNamesSection = nullptr; // Used only by selected targets. 796 DwarfAccelObjCSection = nullptr; // Used only by selected targets. 797 DwarfAccelNamespaceSection = nullptr; // Used only by selected targets. 798 DwarfAccelTypesSection = nullptr; // Used only by selected targets. 799 800 TT = TheTriple; 801 802 Triple::ArchType Arch = TT.getArch(); 803 // FIXME: Checking for Arch here to filter out bogus triples such as 804 // cellspu-apple-darwin. Perhaps we should fix in Triple? 805 if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 806 Arch == Triple::arm || Arch == Triple::thumb || 807 Arch == Triple::aarch64 || 808 Arch == Triple::ppc || Arch == Triple::ppc64 || 809 Arch == Triple::UnknownArch) && 810 TT.isOSBinFormatMachO()) { 811 Env = IsMachO; 812 initMachOMCObjectFileInfo(TT); 813 } else if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 814 Arch == Triple::arm || Arch == Triple::thumb) && 815 (TT.isOSWindows() && TT.getObjectFormat() == Triple::COFF)) { 816 Env = IsCOFF; 817 initCOFFMCObjectFileInfo(TT); 818 } else { 819 Env = IsELF; 820 initELFMCObjectFileInfo(TT); 821 } 822 } 823 824 void MCObjectFileInfo::InitMCObjectFileInfo(StringRef TT, Reloc::Model RM, 825 CodeModel::Model CM, 826 MCContext &ctx) { 827 InitMCObjectFileInfo(Triple(TT), RM, CM, ctx); 828 } 829 830 MCSection *MCObjectFileInfo::getDwarfTypesSection(uint64_t Hash) const { 831 return Ctx->getELFSection(".debug_types", ELF::SHT_PROGBITS, ELF::SHF_GROUP, 832 0, utostr(Hash)); 833 } 834