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 if (T.isOSDarwin() && T.getArch() == Triple::aarch64) 53 SupportsCompactUnwindWithoutEHFrame = true; 54 55 if (T.isWatchOS()) 56 OmitDwarfIfHaveCompactUnwind = true; 57 58 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel 59 | dwarf::DW_EH_PE_sdata4; 60 LSDAEncoding = FDECFIEncoding = dwarf::DW_EH_PE_pcrel; 61 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 62 dwarf::DW_EH_PE_sdata4; 63 64 // .comm doesn't support alignment before Leopard. 65 if (T.isMacOSX() && T.isMacOSXVersionLT(10, 5)) 66 CommDirectiveSupportsAlignment = false; 67 68 TextSection // .text 69 = Ctx->getMachOSection("__TEXT", "__text", 70 MachO::S_ATTR_PURE_INSTRUCTIONS, 71 SectionKind::getText()); 72 DataSection // .data 73 = Ctx->getMachOSection("__DATA", "__data", 0, 74 SectionKind::getDataRel()); 75 76 // BSSSection might not be expected initialized on msvc. 77 BSSSection = nullptr; 78 79 TLSDataSection // .tdata 80 = Ctx->getMachOSection("__DATA", "__thread_data", 81 MachO::S_THREAD_LOCAL_REGULAR, 82 SectionKind::getDataRel()); 83 TLSBSSSection // .tbss 84 = Ctx->getMachOSection("__DATA", "__thread_bss", 85 MachO::S_THREAD_LOCAL_ZEROFILL, 86 SectionKind::getThreadBSS()); 87 88 // TODO: Verify datarel below. 89 TLSTLVSection // .tlv 90 = Ctx->getMachOSection("__DATA", "__thread_vars", 91 MachO::S_THREAD_LOCAL_VARIABLES, 92 SectionKind::getDataRel()); 93 94 TLSThreadInitSection 95 = Ctx->getMachOSection("__DATA", "__thread_init", 96 MachO::S_THREAD_LOCAL_INIT_FUNCTION_POINTERS, 97 SectionKind::getDataRel()); 98 99 CStringSection // .cstring 100 = Ctx->getMachOSection("__TEXT", "__cstring", 101 MachO::S_CSTRING_LITERALS, 102 SectionKind::getMergeable1ByteCString()); 103 UStringSection 104 = Ctx->getMachOSection("__TEXT","__ustring", 0, 105 SectionKind::getMergeable2ByteCString()); 106 FourByteConstantSection // .literal4 107 = Ctx->getMachOSection("__TEXT", "__literal4", 108 MachO::S_4BYTE_LITERALS, 109 SectionKind::getMergeableConst4()); 110 EightByteConstantSection // .literal8 111 = Ctx->getMachOSection("__TEXT", "__literal8", 112 MachO::S_8BYTE_LITERALS, 113 SectionKind::getMergeableConst8()); 114 115 SixteenByteConstantSection // .literal16 116 = Ctx->getMachOSection("__TEXT", "__literal16", 117 MachO::S_16BYTE_LITERALS, 118 SectionKind::getMergeableConst16()); 119 120 ReadOnlySection // .const 121 = Ctx->getMachOSection("__TEXT", "__const", 0, 122 SectionKind::getReadOnly()); 123 124 // If the target is not powerpc, map the coal sections to the non-coal 125 // sections. 126 // 127 // "__TEXT/__textcoal_nt" => section "__TEXT/__text" 128 // "__TEXT/__const_coal" => section "__TEXT/__const" 129 // "__DATA/__datacoal_nt" => section "__DATA/__data" 130 Triple::ArchType ArchTy = T.getArch(); 131 132 if (ArchTy == Triple::ppc || ArchTy == Triple::ppc64) { 133 TextCoalSection 134 = Ctx->getMachOSection("__TEXT", "__textcoal_nt", 135 MachO::S_COALESCED | 136 MachO::S_ATTR_PURE_INSTRUCTIONS, 137 SectionKind::getText()); 138 ConstTextCoalSection 139 = Ctx->getMachOSection("__TEXT", "__const_coal", 140 MachO::S_COALESCED, 141 SectionKind::getReadOnly()); 142 DataCoalSection 143 = Ctx->getMachOSection("__DATA","__datacoal_nt", 144 MachO::S_COALESCED, 145 SectionKind::getDataRel()); 146 } else { 147 TextCoalSection = TextSection; 148 ConstTextCoalSection = ReadOnlySection; 149 DataCoalSection = DataSection; 150 } 151 152 ConstDataSection // .const_data 153 = Ctx->getMachOSection("__DATA", "__const", 0, 154 SectionKind::getReadOnlyWithRel()); 155 DataCommonSection 156 = Ctx->getMachOSection("__DATA","__common", 157 MachO::S_ZEROFILL, 158 SectionKind::getBSS()); 159 DataBSSSection 160 = Ctx->getMachOSection("__DATA","__bss", MachO::S_ZEROFILL, 161 SectionKind::getBSS()); 162 163 164 LazySymbolPointerSection 165 = Ctx->getMachOSection("__DATA", "__la_symbol_ptr", 166 MachO::S_LAZY_SYMBOL_POINTERS, 167 SectionKind::getMetadata()); 168 NonLazySymbolPointerSection 169 = Ctx->getMachOSection("__DATA", "__nl_symbol_ptr", 170 MachO::S_NON_LAZY_SYMBOL_POINTERS, 171 SectionKind::getMetadata()); 172 173 if (RelocM == Reloc::Static) { 174 StaticCtorSection 175 = Ctx->getMachOSection("__TEXT", "__constructor", 0, 176 SectionKind::getDataRel()); 177 StaticDtorSection 178 = Ctx->getMachOSection("__TEXT", "__destructor", 0, 179 SectionKind::getDataRel()); 180 } else { 181 StaticCtorSection 182 = Ctx->getMachOSection("__DATA", "__mod_init_func", 183 MachO::S_MOD_INIT_FUNC_POINTERS, 184 SectionKind::getDataRel()); 185 StaticDtorSection 186 = Ctx->getMachOSection("__DATA", "__mod_term_func", 187 MachO::S_MOD_TERM_FUNC_POINTERS, 188 SectionKind::getDataRel()); 189 } 190 191 // Exception Handling. 192 LSDASection = Ctx->getMachOSection("__TEXT", "__gcc_except_tab", 0, 193 SectionKind::getReadOnlyWithRel()); 194 195 COFFDebugSymbolsSection = nullptr; 196 197 if (useCompactUnwind(T)) { 198 CompactUnwindSection = 199 Ctx->getMachOSection("__LD", "__compact_unwind", MachO::S_ATTR_DEBUG, 200 SectionKind::getReadOnly()); 201 202 if (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86) 203 CompactUnwindDwarfEHFrameOnly = 0x04000000; // UNWIND_X86_64_MODE_DWARF 204 else if (T.getArch() == Triple::aarch64) 205 CompactUnwindDwarfEHFrameOnly = 0x03000000; // UNWIND_ARM64_MODE_DWARF 206 else if (T.getArch() == Triple::arm || T.getArch() == Triple::thumb) 207 CompactUnwindDwarfEHFrameOnly = 0x04000000; // UNWIND_ARM_MODE_DWARF 208 } 209 210 // Debug Information. 211 DwarfAccelNamesSection = 212 Ctx->getMachOSection("__DWARF", "__apple_names", MachO::S_ATTR_DEBUG, 213 SectionKind::getMetadata(), "names_begin"); 214 DwarfAccelObjCSection = 215 Ctx->getMachOSection("__DWARF", "__apple_objc", MachO::S_ATTR_DEBUG, 216 SectionKind::getMetadata(), "objc_begin"); 217 // 16 character section limit... 218 DwarfAccelNamespaceSection = 219 Ctx->getMachOSection("__DWARF", "__apple_namespac", MachO::S_ATTR_DEBUG, 220 SectionKind::getMetadata(), "namespac_begin"); 221 DwarfAccelTypesSection = 222 Ctx->getMachOSection("__DWARF", "__apple_types", MachO::S_ATTR_DEBUG, 223 SectionKind::getMetadata(), "types_begin"); 224 225 DwarfAbbrevSection = 226 Ctx->getMachOSection("__DWARF", "__debug_abbrev", MachO::S_ATTR_DEBUG, 227 SectionKind::getMetadata(), "section_abbrev"); 228 DwarfInfoSection = 229 Ctx->getMachOSection("__DWARF", "__debug_info", MachO::S_ATTR_DEBUG, 230 SectionKind::getMetadata(), "section_info"); 231 DwarfLineSection = 232 Ctx->getMachOSection("__DWARF", "__debug_line", MachO::S_ATTR_DEBUG, 233 SectionKind::getMetadata(), "section_line"); 234 DwarfFrameSection = 235 Ctx->getMachOSection("__DWARF", "__debug_frame", MachO::S_ATTR_DEBUG, 236 SectionKind::getMetadata()); 237 DwarfPubNamesSection = 238 Ctx->getMachOSection("__DWARF", "__debug_pubnames", MachO::S_ATTR_DEBUG, 239 SectionKind::getMetadata()); 240 DwarfPubTypesSection = 241 Ctx->getMachOSection("__DWARF", "__debug_pubtypes", MachO::S_ATTR_DEBUG, 242 SectionKind::getMetadata()); 243 DwarfGnuPubNamesSection = 244 Ctx->getMachOSection("__DWARF", "__debug_gnu_pubn", MachO::S_ATTR_DEBUG, 245 SectionKind::getMetadata()); 246 DwarfGnuPubTypesSection = 247 Ctx->getMachOSection("__DWARF", "__debug_gnu_pubt", MachO::S_ATTR_DEBUG, 248 SectionKind::getMetadata()); 249 DwarfStrSection = 250 Ctx->getMachOSection("__DWARF", "__debug_str", MachO::S_ATTR_DEBUG, 251 SectionKind::getMetadata(), "info_string"); 252 DwarfLocSection = 253 Ctx->getMachOSection("__DWARF", "__debug_loc", MachO::S_ATTR_DEBUG, 254 SectionKind::getMetadata(), "section_debug_loc"); 255 DwarfARangesSection = 256 Ctx->getMachOSection("__DWARF", "__debug_aranges", MachO::S_ATTR_DEBUG, 257 SectionKind::getMetadata()); 258 DwarfRangesSection = 259 Ctx->getMachOSection("__DWARF", "__debug_ranges", MachO::S_ATTR_DEBUG, 260 SectionKind::getMetadata(), "debug_range"); 261 DwarfDebugInlineSection = 262 Ctx->getMachOSection("__DWARF", "__debug_inlined", MachO::S_ATTR_DEBUG, 263 SectionKind::getMetadata()); 264 StackMapSection = Ctx->getMachOSection("__LLVM_STACKMAPS", "__llvm_stackmaps", 265 0, SectionKind::getMetadata()); 266 267 FaultMapSection = Ctx->getMachOSection("__LLVM_FAULTMAPS", "__llvm_faultmaps", 268 0, SectionKind::getMetadata()); 269 270 TLSExtraDataSection = TLSTLVSection; 271 } 272 273 void MCObjectFileInfo::initELFMCObjectFileInfo(Triple T) { 274 switch (T.getArch()) { 275 case Triple::mips: 276 case Triple::mipsel: 277 FDECFIEncoding = dwarf::DW_EH_PE_sdata4; 278 break; 279 case Triple::mips64: 280 case Triple::mips64el: 281 FDECFIEncoding = dwarf::DW_EH_PE_sdata8; 282 break; 283 case Triple::x86_64: 284 FDECFIEncoding = dwarf::DW_EH_PE_pcrel | 285 ((CMModel == CodeModel::Large) ? dwarf::DW_EH_PE_sdata8 286 : dwarf::DW_EH_PE_sdata4); 287 break; 288 default: 289 FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 290 break; 291 } 292 293 switch (T.getArch()) { 294 case Triple::arm: 295 case Triple::armeb: 296 case Triple::thumb: 297 case Triple::thumbeb: 298 if (Ctx->getAsmInfo()->getExceptionHandlingType() == ExceptionHandling::ARM) 299 break; 300 // Fallthrough if not using EHABI 301 case Triple::ppc: 302 case Triple::x86: 303 PersonalityEncoding = (RelocM == Reloc::PIC_) 304 ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 305 : dwarf::DW_EH_PE_absptr; 306 LSDAEncoding = (RelocM == Reloc::PIC_) 307 ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 308 : dwarf::DW_EH_PE_absptr; 309 TTypeEncoding = (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 break; 313 case Triple::x86_64: 314 if (RelocM == Reloc::PIC_) { 315 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 316 ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 317 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 318 LSDAEncoding = dwarf::DW_EH_PE_pcrel | 319 (CMModel == CodeModel::Small 320 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 321 TTypeEncoding = 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 } else { 325 PersonalityEncoding = 326 (CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 327 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 328 LSDAEncoding = (CMModel == CodeModel::Small) 329 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 330 TTypeEncoding = (CMModel == CodeModel::Small) 331 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 332 } 333 break; 334 case Triple::aarch64: 335 case Triple::aarch64_be: 336 // The small model guarantees static code/data size < 4GB, but not where it 337 // will be in memory. Most of these could end up >2GB away so even a signed 338 // pc-relative 32-bit address is insufficient, theoretically. 339 if (RelocM == Reloc::PIC_) { 340 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 341 dwarf::DW_EH_PE_sdata8; 342 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8; 343 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 344 dwarf::DW_EH_PE_sdata8; 345 } else { 346 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 347 LSDAEncoding = dwarf::DW_EH_PE_absptr; 348 TTypeEncoding = dwarf::DW_EH_PE_absptr; 349 } 350 break; 351 case Triple::mips: 352 case Triple::mipsel: 353 case Triple::mips64: 354 case Triple::mips64el: 355 // MIPS uses indirect pointer to refer personality functions and types, so 356 // that the eh_frame section can be read-only. DW.ref.personality will be 357 // generated for relocation. 358 PersonalityEncoding = dwarf::DW_EH_PE_indirect; 359 // FIXME: The N64 ABI probably ought to use DW_EH_PE_sdata8 but we can't 360 // identify N64 from just a triple. 361 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 362 dwarf::DW_EH_PE_sdata4; 363 // We don't support PC-relative LSDA references in GAS so we use the default 364 // DW_EH_PE_absptr for those. 365 break; 366 case Triple::ppc64: 367 case Triple::ppc64le: 368 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 369 dwarf::DW_EH_PE_udata8; 370 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8; 371 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 372 dwarf::DW_EH_PE_udata8; 373 break; 374 case Triple::sparcel: 375 case Triple::sparc: 376 if (RelocM == Reloc::PIC_) { 377 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 378 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 379 dwarf::DW_EH_PE_sdata4; 380 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 381 dwarf::DW_EH_PE_sdata4; 382 } else { 383 LSDAEncoding = dwarf::DW_EH_PE_absptr; 384 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 385 TTypeEncoding = dwarf::DW_EH_PE_absptr; 386 } 387 break; 388 case Triple::sparcv9: 389 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 390 if (RelocM == Reloc::PIC_) { 391 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 392 dwarf::DW_EH_PE_sdata4; 393 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 394 dwarf::DW_EH_PE_sdata4; 395 } else { 396 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 397 TTypeEncoding = dwarf::DW_EH_PE_absptr; 398 } 399 break; 400 case Triple::systemz: 401 // All currently-defined code models guarantee that 4-byte PC-relative 402 // values will be in range. 403 if (RelocM == Reloc::PIC_) { 404 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 405 dwarf::DW_EH_PE_sdata4; 406 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 407 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 408 dwarf::DW_EH_PE_sdata4; 409 } else { 410 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 411 LSDAEncoding = dwarf::DW_EH_PE_absptr; 412 TTypeEncoding = dwarf::DW_EH_PE_absptr; 413 } 414 break; 415 default: 416 break; 417 } 418 419 // Solaris requires different flags for .eh_frame to seemingly every other 420 // platform. 421 EHSectionType = ELF::SHT_PROGBITS; 422 EHSectionFlags = ELF::SHF_ALLOC; 423 if (T.isOSSolaris()) { 424 if (T.getArch() == Triple::x86_64) 425 EHSectionType = ELF::SHT_X86_64_UNWIND; 426 else 427 EHSectionFlags |= ELF::SHF_WRITE; 428 } 429 430 // ELF 431 BSSSection = Ctx->getELFSection(".bss", ELF::SHT_NOBITS, 432 ELF::SHF_WRITE | ELF::SHF_ALLOC); 433 434 TextSection = Ctx->getELFSection(".text", ELF::SHT_PROGBITS, 435 ELF::SHF_EXECINSTR | ELF::SHF_ALLOC); 436 437 DataSection = Ctx->getELFSection(".data", ELF::SHT_PROGBITS, 438 ELF::SHF_WRITE | ELF::SHF_ALLOC); 439 440 ReadOnlySection = 441 Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 442 443 TLSDataSection = 444 Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS, 445 ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE); 446 447 TLSBSSSection = Ctx->getELFSection( 448 ".tbss", ELF::SHT_NOBITS, ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE); 449 450 DataRelSection = Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS, 451 ELF::SHF_ALLOC | ELF::SHF_WRITE); 452 453 DataRelLocalSection = Ctx->getELFSection(".data.rel.local", ELF::SHT_PROGBITS, 454 ELF::SHF_ALLOC | ELF::SHF_WRITE); 455 456 DataRelROSection = Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS, 457 ELF::SHF_ALLOC | ELF::SHF_WRITE); 458 459 DataRelROLocalSection = Ctx->getELFSection( 460 ".data.rel.ro.local", ELF::SHT_PROGBITS, ELF::SHF_ALLOC | ELF::SHF_WRITE); 461 462 MergeableConst4Section = 463 Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS, 464 ELF::SHF_ALLOC | ELF::SHF_MERGE, 4, ""); 465 466 MergeableConst8Section = 467 Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS, 468 ELF::SHF_ALLOC | ELF::SHF_MERGE, 8, ""); 469 470 MergeableConst16Section = 471 Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS, 472 ELF::SHF_ALLOC | ELF::SHF_MERGE, 16, ""); 473 474 StaticCtorSection = Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS, 475 ELF::SHF_ALLOC | ELF::SHF_WRITE); 476 477 StaticDtorSection = Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS, 478 ELF::SHF_ALLOC | ELF::SHF_WRITE); 479 480 // Exception Handling Sections. 481 482 // FIXME: We're emitting LSDA info into a readonly section on ELF, even though 483 // it contains relocatable pointers. In PIC mode, this is probably a big 484 // runtime hit for C++ apps. Either the contents of the LSDA need to be 485 // adjusted or this should be a data section. 486 LSDASection = Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS, 487 ELF::SHF_ALLOC); 488 489 COFFDebugSymbolsSection = nullptr; 490 491 // Debug Info Sections. 492 DwarfAbbrevSection = Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0, 493 "section_abbrev"); 494 DwarfInfoSection = 495 Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0, "section_info"); 496 DwarfLineSection = Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0); 497 DwarfFrameSection = Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0); 498 DwarfPubNamesSection = 499 Ctx->getELFSection(".debug_pubnames", ELF::SHT_PROGBITS, 0); 500 DwarfPubTypesSection = 501 Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0); 502 DwarfGnuPubNamesSection = 503 Ctx->getELFSection(".debug_gnu_pubnames", ELF::SHT_PROGBITS, 0); 504 DwarfGnuPubTypesSection = 505 Ctx->getELFSection(".debug_gnu_pubtypes", ELF::SHT_PROGBITS, 0); 506 DwarfStrSection = 507 Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS, 508 ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, ""); 509 DwarfLocSection = Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0); 510 DwarfARangesSection = 511 Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0); 512 DwarfRangesSection = 513 Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0, "debug_range"); 514 515 // DWARF5 Experimental Debug Info 516 517 // Accelerator Tables 518 DwarfAccelNamesSection = 519 Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0, "names_begin"); 520 DwarfAccelObjCSection = 521 Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0, "objc_begin"); 522 DwarfAccelNamespaceSection = Ctx->getELFSection( 523 ".apple_namespaces", ELF::SHT_PROGBITS, 0, "namespac_begin"); 524 DwarfAccelTypesSection = 525 Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0, "types_begin"); 526 527 // Fission Sections 528 DwarfInfoDWOSection = 529 Ctx->getELFSection(".debug_info.dwo", ELF::SHT_PROGBITS, 0); 530 DwarfTypesDWOSection = 531 Ctx->getELFSection(".debug_types.dwo", ELF::SHT_PROGBITS, 0); 532 DwarfAbbrevDWOSection = 533 Ctx->getELFSection(".debug_abbrev.dwo", ELF::SHT_PROGBITS, 0); 534 DwarfStrDWOSection = 535 Ctx->getELFSection(".debug_str.dwo", ELF::SHT_PROGBITS, 536 ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, ""); 537 DwarfLineDWOSection = 538 Ctx->getELFSection(".debug_line.dwo", ELF::SHT_PROGBITS, 0); 539 DwarfLocDWOSection = 540 Ctx->getELFSection(".debug_loc.dwo", ELF::SHT_PROGBITS, 0, "skel_loc"); 541 DwarfStrOffDWOSection = 542 Ctx->getELFSection(".debug_str_offsets.dwo", ELF::SHT_PROGBITS, 0); 543 DwarfAddrSection = 544 Ctx->getELFSection(".debug_addr", ELF::SHT_PROGBITS, 0, "addr_sec"); 545 546 StackMapSection = 547 Ctx->getELFSection(".llvm_stackmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 548 549 FaultMapSection = 550 Ctx->getELFSection(".llvm_faultmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 551 } 552 553 void MCObjectFileInfo::initCOFFMCObjectFileInfo(Triple T) { 554 bool IsWoA = T.getArch() == Triple::arm || T.getArch() == Triple::thumb; 555 556 CommDirectiveSupportsAlignment = true; 557 558 // COFF 559 BSSSection = Ctx->getCOFFSection( 560 ".bss", COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA | 561 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 562 SectionKind::getBSS()); 563 TextSection = Ctx->getCOFFSection( 564 ".text", 565 (IsWoA ? COFF::IMAGE_SCN_MEM_16BIT : (COFF::SectionCharacteristics)0) | 566 COFF::IMAGE_SCN_CNT_CODE | COFF::IMAGE_SCN_MEM_EXECUTE | 567 COFF::IMAGE_SCN_MEM_READ, 568 SectionKind::getText()); 569 DataSection = Ctx->getCOFFSection( 570 ".data", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ | 571 COFF::IMAGE_SCN_MEM_WRITE, 572 SectionKind::getDataRel()); 573 ReadOnlySection = Ctx->getCOFFSection( 574 ".rdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 575 SectionKind::getReadOnly()); 576 577 if (T.isKnownWindowsMSVCEnvironment() || T.isWindowsItaniumEnvironment()) { 578 StaticCtorSection = 579 Ctx->getCOFFSection(".CRT$XCU", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 580 COFF::IMAGE_SCN_MEM_READ, 581 SectionKind::getReadOnly()); 582 StaticDtorSection = 583 Ctx->getCOFFSection(".CRT$XTX", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 584 COFF::IMAGE_SCN_MEM_READ, 585 SectionKind::getReadOnly()); 586 } else { 587 StaticCtorSection = Ctx->getCOFFSection( 588 ".ctors", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 589 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 590 SectionKind::getDataRel()); 591 StaticDtorSection = Ctx->getCOFFSection( 592 ".dtors", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 593 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 594 SectionKind::getDataRel()); 595 } 596 597 // FIXME: We're emitting LSDA info into a readonly section on COFF, even 598 // though it contains relocatable pointers. In PIC mode, this is probably a 599 // big runtime hit for C++ apps. Either the contents of the LSDA need to be 600 // adjusted or this should be a data section. 601 assert(T.isOSWindows() && "Windows is the only supported COFF target"); 602 if (T.getArch() == Triple::x86_64) { 603 // On Windows 64 with SEH, the LSDA is emitted into the .xdata section 604 LSDASection = nullptr; 605 } else { 606 LSDASection = Ctx->getCOFFSection(".gcc_except_table", 607 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 608 COFF::IMAGE_SCN_MEM_READ, 609 SectionKind::getReadOnly()); 610 } 611 612 // Debug info. 613 COFFDebugSymbolsSection = 614 Ctx->getCOFFSection(".debug$S", COFF::IMAGE_SCN_MEM_DISCARDABLE | 615 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 616 COFF::IMAGE_SCN_MEM_READ, 617 SectionKind::getMetadata()); 618 619 DwarfAbbrevSection = Ctx->getCOFFSection( 620 ".debug_abbrev", 621 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 622 COFF::IMAGE_SCN_MEM_READ, 623 SectionKind::getMetadata(), "section_abbrev"); 624 DwarfInfoSection = Ctx->getCOFFSection( 625 ".debug_info", 626 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 627 COFF::IMAGE_SCN_MEM_READ, 628 SectionKind::getMetadata(), "section_info"); 629 DwarfLineSection = Ctx->getCOFFSection( 630 ".debug_line", 631 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 632 COFF::IMAGE_SCN_MEM_READ, 633 SectionKind::getMetadata(), "section_line"); 634 635 DwarfFrameSection = Ctx->getCOFFSection( 636 ".debug_frame", 637 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 638 COFF::IMAGE_SCN_MEM_READ, 639 SectionKind::getMetadata()); 640 DwarfPubNamesSection = Ctx->getCOFFSection( 641 ".debug_pubnames", 642 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 643 COFF::IMAGE_SCN_MEM_READ, 644 SectionKind::getMetadata()); 645 DwarfPubTypesSection = Ctx->getCOFFSection( 646 ".debug_pubtypes", 647 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 648 COFF::IMAGE_SCN_MEM_READ, 649 SectionKind::getMetadata()); 650 DwarfGnuPubNamesSection = Ctx->getCOFFSection( 651 ".debug_gnu_pubnames", 652 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 653 COFF::IMAGE_SCN_MEM_READ, 654 SectionKind::getMetadata()); 655 DwarfGnuPubTypesSection = Ctx->getCOFFSection( 656 ".debug_gnu_pubtypes", 657 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 658 COFF::IMAGE_SCN_MEM_READ, 659 SectionKind::getMetadata()); 660 DwarfStrSection = Ctx->getCOFFSection( 661 ".debug_str", 662 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 663 COFF::IMAGE_SCN_MEM_READ, 664 SectionKind::getMetadata(), "info_string"); 665 DwarfLocSection = Ctx->getCOFFSection( 666 ".debug_loc", 667 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 668 COFF::IMAGE_SCN_MEM_READ, 669 SectionKind::getMetadata(), "section_debug_loc"); 670 DwarfARangesSection = Ctx->getCOFFSection( 671 ".debug_aranges", 672 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 673 COFF::IMAGE_SCN_MEM_READ, 674 SectionKind::getMetadata()); 675 DwarfRangesSection = Ctx->getCOFFSection( 676 ".debug_ranges", 677 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 678 COFF::IMAGE_SCN_MEM_READ, 679 SectionKind::getMetadata(), "debug_range"); 680 DwarfInfoDWOSection = Ctx->getCOFFSection( 681 ".debug_info.dwo", 682 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 683 COFF::IMAGE_SCN_MEM_READ, 684 SectionKind::getMetadata(), "section_info_dwo"); 685 DwarfTypesDWOSection = Ctx->getCOFFSection( 686 ".debug_types.dwo", 687 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 688 COFF::IMAGE_SCN_MEM_READ, 689 SectionKind::getMetadata(), "section_types_dwo"); 690 DwarfAbbrevDWOSection = Ctx->getCOFFSection( 691 ".debug_abbrev.dwo", 692 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 693 COFF::IMAGE_SCN_MEM_READ, 694 SectionKind::getMetadata(), "section_abbrev_dwo"); 695 DwarfStrDWOSection = Ctx->getCOFFSection( 696 ".debug_str.dwo", 697 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 698 COFF::IMAGE_SCN_MEM_READ, 699 SectionKind::getMetadata(), "skel_string"); 700 DwarfLineDWOSection = Ctx->getCOFFSection( 701 ".debug_line.dwo", 702 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 703 COFF::IMAGE_SCN_MEM_READ, 704 SectionKind::getMetadata()); 705 DwarfLocDWOSection = Ctx->getCOFFSection( 706 ".debug_loc.dwo", 707 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 708 COFF::IMAGE_SCN_MEM_READ, 709 SectionKind::getMetadata(), "skel_loc"); 710 DwarfStrOffDWOSection = Ctx->getCOFFSection( 711 ".debug_str_offsets.dwo", 712 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 713 COFF::IMAGE_SCN_MEM_READ, 714 SectionKind::getMetadata()); 715 DwarfAddrSection = Ctx->getCOFFSection( 716 ".debug_addr", 717 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 718 COFF::IMAGE_SCN_MEM_READ, 719 SectionKind::getMetadata(), "addr_sec"); 720 DwarfAccelNamesSection = Ctx->getCOFFSection( 721 ".apple_names", 722 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 723 COFF::IMAGE_SCN_MEM_READ, 724 SectionKind::getMetadata(), "names_begin"); 725 DwarfAccelNamespaceSection = Ctx->getCOFFSection( 726 ".apple_namespaces", 727 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 728 COFF::IMAGE_SCN_MEM_READ, 729 SectionKind::getMetadata(), "namespac_begin"); 730 DwarfAccelTypesSection = Ctx->getCOFFSection( 731 ".apple_types", 732 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 733 COFF::IMAGE_SCN_MEM_READ, 734 SectionKind::getMetadata(), "types_begin"); 735 DwarfAccelObjCSection = Ctx->getCOFFSection( 736 ".apple_objc", 737 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 738 COFF::IMAGE_SCN_MEM_READ, 739 SectionKind::getMetadata(), "objc_begin"); 740 741 DrectveSection = Ctx->getCOFFSection( 742 ".drectve", COFF::IMAGE_SCN_LNK_INFO | COFF::IMAGE_SCN_LNK_REMOVE, 743 SectionKind::getMetadata()); 744 745 PDataSection = Ctx->getCOFFSection( 746 ".pdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 747 SectionKind::getDataRel()); 748 749 XDataSection = Ctx->getCOFFSection( 750 ".xdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 751 SectionKind::getDataRel()); 752 753 SXDataSection = Ctx->getCOFFSection(".sxdata", COFF::IMAGE_SCN_LNK_INFO, 754 SectionKind::getMetadata()); 755 756 TLSDataSection = Ctx->getCOFFSection( 757 ".tls$", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ | 758 COFF::IMAGE_SCN_MEM_WRITE, 759 SectionKind::getDataRel()); 760 761 StackMapSection = Ctx->getCOFFSection(".llvm_stackmaps", 762 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 763 COFF::IMAGE_SCN_MEM_READ, 764 SectionKind::getReadOnly()); 765 } 766 767 void MCObjectFileInfo::InitMCObjectFileInfo(const Triple &TheTriple, 768 Reloc::Model relocm, 769 CodeModel::Model cm, 770 MCContext &ctx) { 771 RelocM = relocm; 772 CMModel = cm; 773 Ctx = &ctx; 774 775 // Common. 776 CommDirectiveSupportsAlignment = true; 777 SupportsWeakOmittedEHFrame = true; 778 SupportsCompactUnwindWithoutEHFrame = false; 779 OmitDwarfIfHaveCompactUnwind = false; 780 781 PersonalityEncoding = LSDAEncoding = FDECFIEncoding = TTypeEncoding = 782 dwarf::DW_EH_PE_absptr; 783 784 CompactUnwindDwarfEHFrameOnly = 0; 785 786 EHFrameSection = nullptr; // Created on demand. 787 CompactUnwindSection = nullptr; // Used only by selected targets. 788 DwarfAccelNamesSection = nullptr; // Used only by selected targets. 789 DwarfAccelObjCSection = nullptr; // Used only by selected targets. 790 DwarfAccelNamespaceSection = nullptr; // Used only by selected targets. 791 DwarfAccelTypesSection = nullptr; // Used only by selected targets. 792 793 TT = TheTriple; 794 795 Triple::ArchType Arch = TT.getArch(); 796 // FIXME: Checking for Arch here to filter out bogus triples such as 797 // cellspu-apple-darwin. Perhaps we should fix in Triple? 798 if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 799 Arch == Triple::arm || Arch == Triple::thumb || 800 Arch == Triple::aarch64 || 801 Arch == Triple::ppc || Arch == Triple::ppc64 || 802 Arch == Triple::UnknownArch) && 803 TT.isOSBinFormatMachO()) { 804 Env = IsMachO; 805 initMachOMCObjectFileInfo(TT); 806 } else if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 807 Arch == Triple::arm || Arch == Triple::thumb) && 808 (TT.isOSWindows() && TT.getObjectFormat() == Triple::COFF)) { 809 Env = IsCOFF; 810 initCOFFMCObjectFileInfo(TT); 811 } else { 812 Env = IsELF; 813 initELFMCObjectFileInfo(TT); 814 } 815 } 816 817 void MCObjectFileInfo::InitMCObjectFileInfo(StringRef TT, Reloc::Model RM, 818 CodeModel::Model CM, 819 MCContext &ctx) { 820 InitMCObjectFileInfo(Triple(TT), RM, CM, ctx); 821 } 822 823 MCSection *MCObjectFileInfo::getDwarfTypesSection(uint64_t Hash) const { 824 return Ctx->getELFSection(".debug_types", ELF::SHT_PROGBITS, ELF::SHF_GROUP, 825 0, utostr(Hash)); 826 } 827 828 void MCObjectFileInfo::InitEHFrameSection() { 829 if (Env == IsMachO) 830 EHFrameSection = 831 Ctx->getMachOSection("__TEXT", "__eh_frame", 832 MachO::S_COALESCED | 833 MachO::S_ATTR_NO_TOC | 834 MachO::S_ATTR_STRIP_STATIC_SYMS | 835 MachO::S_ATTR_LIVE_SUPPORT, 836 SectionKind::getReadOnly()); 837 else if (Env == IsELF) 838 EHFrameSection = 839 Ctx->getELFSection(".eh_frame", EHSectionType, EHSectionFlags); 840 else 841 EHFrameSection = 842 Ctx->getCOFFSection(".eh_frame", 843 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 844 COFF::IMAGE_SCN_MEM_READ | 845 COFF::IMAGE_SCN_MEM_WRITE, 846 SectionKind::getDataRel()); 847 } 848