1 //===-- MObjectFileInfo.cpp - Object File Information ---------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #include "llvm/MC/MCObjectFileInfo.h" 11 #include "llvm/ADT/StringExtras.h" 12 #include "llvm/ADT/Triple.h" 13 #include "llvm/MC/MCAsmInfo.h" 14 #include "llvm/MC/MCContext.h" 15 #include "llvm/MC/MCSection.h" 16 #include "llvm/MC/MCSectionCOFF.h" 17 #include "llvm/MC/MCSectionELF.h" 18 #include "llvm/MC/MCSectionMachO.h" 19 using namespace llvm; 20 21 static bool useCompactUnwind(const Triple &T) { 22 // Only on darwin. 23 if (!T.isOSDarwin()) 24 return false; 25 26 // aarch64 always has it. 27 if (T.getArch() == Triple::aarch64) 28 return true; 29 30 // Use it on newer version of OS X. 31 if (T.isMacOSX() && !T.isMacOSXVersionLT(10, 6)) 32 return true; 33 34 // And the iOS simulator. 35 if (T.isiOS() && 36 (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86)) 37 return true; 38 39 return false; 40 } 41 42 void MCObjectFileInfo::InitMachOMCObjectFileInfo(Triple T) { 43 // MachO 44 SupportsWeakOmittedEHFrame = false; 45 46 if (T.isOSDarwin() && T.getArch() == Triple::aarch64) 47 SupportsCompactUnwindWithoutEHFrame = true; 48 49 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel 50 | dwarf::DW_EH_PE_sdata4; 51 LSDAEncoding = FDECFIEncoding = dwarf::DW_EH_PE_pcrel; 52 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 53 dwarf::DW_EH_PE_sdata4; 54 55 // .comm doesn't support alignment before Leopard. 56 if (T.isMacOSX() && T.isMacOSXVersionLT(10, 5)) 57 CommDirectiveSupportsAlignment = false; 58 59 TextSection // .text 60 = Ctx->getMachOSection("__TEXT", "__text", 61 MachO::S_ATTR_PURE_INSTRUCTIONS, 62 SectionKind::getText()); 63 DataSection // .data 64 = Ctx->getMachOSection("__DATA", "__data", 0, 65 SectionKind::getDataRel()); 66 67 // BSSSection might not be expected initialized on msvc. 68 BSSSection = nullptr; 69 70 TLSDataSection // .tdata 71 = Ctx->getMachOSection("__DATA", "__thread_data", 72 MachO::S_THREAD_LOCAL_REGULAR, 73 SectionKind::getDataRel()); 74 TLSBSSSection // .tbss 75 = Ctx->getMachOSection("__DATA", "__thread_bss", 76 MachO::S_THREAD_LOCAL_ZEROFILL, 77 SectionKind::getThreadBSS()); 78 79 // TODO: Verify datarel below. 80 TLSTLVSection // .tlv 81 = Ctx->getMachOSection("__DATA", "__thread_vars", 82 MachO::S_THREAD_LOCAL_VARIABLES, 83 SectionKind::getDataRel()); 84 85 TLSThreadInitSection 86 = Ctx->getMachOSection("__DATA", "__thread_init", 87 MachO::S_THREAD_LOCAL_INIT_FUNCTION_POINTERS, 88 SectionKind::getDataRel()); 89 90 CStringSection // .cstring 91 = Ctx->getMachOSection("__TEXT", "__cstring", 92 MachO::S_CSTRING_LITERALS, 93 SectionKind::getMergeable1ByteCString()); 94 UStringSection 95 = Ctx->getMachOSection("__TEXT","__ustring", 0, 96 SectionKind::getMergeable2ByteCString()); 97 FourByteConstantSection // .literal4 98 = Ctx->getMachOSection("__TEXT", "__literal4", 99 MachO::S_4BYTE_LITERALS, 100 SectionKind::getMergeableConst4()); 101 EightByteConstantSection // .literal8 102 = Ctx->getMachOSection("__TEXT", "__literal8", 103 MachO::S_8BYTE_LITERALS, 104 SectionKind::getMergeableConst8()); 105 106 SixteenByteConstantSection // .literal16 107 = Ctx->getMachOSection("__TEXT", "__literal16", 108 MachO::S_16BYTE_LITERALS, 109 SectionKind::getMergeableConst16()); 110 111 ReadOnlySection // .const 112 = Ctx->getMachOSection("__TEXT", "__const", 0, 113 SectionKind::getReadOnly()); 114 115 TextCoalSection 116 = Ctx->getMachOSection("__TEXT", "__textcoal_nt", 117 MachO::S_COALESCED | 118 MachO::S_ATTR_PURE_INSTRUCTIONS, 119 SectionKind::getText()); 120 ConstTextCoalSection 121 = Ctx->getMachOSection("__TEXT", "__const_coal", 122 MachO::S_COALESCED, 123 SectionKind::getReadOnly()); 124 ConstDataSection // .const_data 125 = Ctx->getMachOSection("__DATA", "__const", 0, 126 SectionKind::getReadOnlyWithRel()); 127 DataCoalSection 128 = Ctx->getMachOSection("__DATA","__datacoal_nt", 129 MachO::S_COALESCED, 130 SectionKind::getDataRel()); 131 DataCommonSection 132 = Ctx->getMachOSection("__DATA","__common", 133 MachO::S_ZEROFILL, 134 SectionKind::getBSS()); 135 DataBSSSection 136 = Ctx->getMachOSection("__DATA","__bss", MachO::S_ZEROFILL, 137 SectionKind::getBSS()); 138 139 140 LazySymbolPointerSection 141 = Ctx->getMachOSection("__DATA", "__la_symbol_ptr", 142 MachO::S_LAZY_SYMBOL_POINTERS, 143 SectionKind::getMetadata()); 144 NonLazySymbolPointerSection 145 = Ctx->getMachOSection("__DATA", "__nl_symbol_ptr", 146 MachO::S_NON_LAZY_SYMBOL_POINTERS, 147 SectionKind::getMetadata()); 148 149 if (RelocM == Reloc::Static) { 150 StaticCtorSection 151 = Ctx->getMachOSection("__TEXT", "__constructor", 0, 152 SectionKind::getDataRel()); 153 StaticDtorSection 154 = Ctx->getMachOSection("__TEXT", "__destructor", 0, 155 SectionKind::getDataRel()); 156 } else { 157 StaticCtorSection 158 = Ctx->getMachOSection("__DATA", "__mod_init_func", 159 MachO::S_MOD_INIT_FUNC_POINTERS, 160 SectionKind::getDataRel()); 161 StaticDtorSection 162 = Ctx->getMachOSection("__DATA", "__mod_term_func", 163 MachO::S_MOD_TERM_FUNC_POINTERS, 164 SectionKind::getDataRel()); 165 } 166 167 // Exception Handling. 168 LSDASection = Ctx->getMachOSection("__TEXT", "__gcc_except_tab", 0, 169 SectionKind::getReadOnlyWithRel()); 170 171 COFFDebugSymbolsSection = nullptr; 172 173 if (useCompactUnwind(T)) { 174 CompactUnwindSection = 175 Ctx->getMachOSection("__LD", "__compact_unwind", MachO::S_ATTR_DEBUG, 176 SectionKind::getReadOnly()); 177 178 if (T.getArch() == Triple::x86_64 || T.getArch() == Triple::x86) 179 CompactUnwindDwarfEHFrameOnly = 0x04000000; 180 else if (T.getArch() == Triple::aarch64) 181 CompactUnwindDwarfEHFrameOnly = 0x03000000; 182 } 183 184 // Debug Information. 185 DwarfAccelNamesSection = 186 Ctx->getMachOSection("__DWARF", "__apple_names", 187 MachO::S_ATTR_DEBUG, 188 SectionKind::getMetadata()); 189 DwarfAccelObjCSection = 190 Ctx->getMachOSection("__DWARF", "__apple_objc", 191 MachO::S_ATTR_DEBUG, 192 SectionKind::getMetadata()); 193 // 16 character section limit... 194 DwarfAccelNamespaceSection = 195 Ctx->getMachOSection("__DWARF", "__apple_namespac", 196 MachO::S_ATTR_DEBUG, 197 SectionKind::getMetadata()); 198 DwarfAccelTypesSection = 199 Ctx->getMachOSection("__DWARF", "__apple_types", 200 MachO::S_ATTR_DEBUG, 201 SectionKind::getMetadata()); 202 203 DwarfAbbrevSection = 204 Ctx->getMachOSection("__DWARF", "__debug_abbrev", 205 MachO::S_ATTR_DEBUG, 206 SectionKind::getMetadata()); 207 DwarfInfoSection = 208 Ctx->getMachOSection("__DWARF", "__debug_info", 209 MachO::S_ATTR_DEBUG, 210 SectionKind::getMetadata()); 211 DwarfLineSection = 212 Ctx->getMachOSection("__DWARF", "__debug_line", 213 MachO::S_ATTR_DEBUG, 214 SectionKind::getMetadata()); 215 DwarfFrameSection = 216 Ctx->getMachOSection("__DWARF", "__debug_frame", 217 MachO::S_ATTR_DEBUG, 218 SectionKind::getMetadata()); 219 DwarfPubNamesSection = 220 Ctx->getMachOSection("__DWARF", "__debug_pubnames", 221 MachO::S_ATTR_DEBUG, 222 SectionKind::getMetadata()); 223 DwarfPubTypesSection = 224 Ctx->getMachOSection("__DWARF", "__debug_pubtypes", 225 MachO::S_ATTR_DEBUG, 226 SectionKind::getMetadata()); 227 DwarfGnuPubNamesSection = 228 Ctx->getMachOSection("__DWARF", "__debug_gnu_pubn", 229 MachO::S_ATTR_DEBUG, 230 SectionKind::getMetadata()); 231 DwarfGnuPubTypesSection = 232 Ctx->getMachOSection("__DWARF", "__debug_gnu_pubt", 233 MachO::S_ATTR_DEBUG, 234 SectionKind::getMetadata()); 235 DwarfStrSection = 236 Ctx->getMachOSection("__DWARF", "__debug_str", 237 MachO::S_ATTR_DEBUG, 238 SectionKind::getMetadata()); 239 DwarfLocSection = 240 Ctx->getMachOSection("__DWARF", "__debug_loc", 241 MachO::S_ATTR_DEBUG, 242 SectionKind::getMetadata()); 243 DwarfARangesSection = 244 Ctx->getMachOSection("__DWARF", "__debug_aranges", 245 MachO::S_ATTR_DEBUG, 246 SectionKind::getMetadata()); 247 DwarfRangesSection = 248 Ctx->getMachOSection("__DWARF", "__debug_ranges", 249 MachO::S_ATTR_DEBUG, 250 SectionKind::getMetadata()); 251 DwarfDebugInlineSection = 252 Ctx->getMachOSection("__DWARF", "__debug_inlined", 253 MachO::S_ATTR_DEBUG, 254 SectionKind::getMetadata()); 255 StackMapSection = 256 Ctx->getMachOSection("__LLVM_STACKMAPS", "__llvm_stackmaps", 0, 257 SectionKind::getMetadata()); 258 259 TLSExtraDataSection = TLSTLVSection; 260 } 261 262 void MCObjectFileInfo::InitELFMCObjectFileInfo(Triple T) { 263 switch (T.getArch()) { 264 case Triple::mips: 265 case Triple::mipsel: 266 FDECFIEncoding = dwarf::DW_EH_PE_sdata4; 267 break; 268 case Triple::mips64: 269 case Triple::mips64el: 270 FDECFIEncoding = dwarf::DW_EH_PE_sdata8; 271 break; 272 case Triple::x86_64: 273 FDECFIEncoding = dwarf::DW_EH_PE_pcrel | 274 ((CMModel == CodeModel::Large) ? dwarf::DW_EH_PE_sdata8 275 : dwarf::DW_EH_PE_sdata4); 276 277 break; 278 default: 279 FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 280 break; 281 } 282 283 switch (T.getArch()) { 284 case Triple::arm: 285 case Triple::armeb: 286 case Triple::thumb: 287 case Triple::thumbeb: 288 if (Ctx->getAsmInfo()->getExceptionHandlingType() == ExceptionHandling::ARM) 289 break; 290 // Fallthrough if not using EHABI 291 case Triple::ppc: 292 case Triple::x86: 293 PersonalityEncoding = (RelocM == Reloc::PIC_) 294 ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 295 : dwarf::DW_EH_PE_absptr; 296 LSDAEncoding = (RelocM == Reloc::PIC_) 297 ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 298 : dwarf::DW_EH_PE_absptr; 299 TTypeEncoding = (RelocM == Reloc::PIC_) 300 ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 301 : dwarf::DW_EH_PE_absptr; 302 break; 303 case Triple::x86_64: 304 if (RelocM == Reloc::PIC_) { 305 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 306 ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 307 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 308 LSDAEncoding = dwarf::DW_EH_PE_pcrel | 309 (CMModel == CodeModel::Small 310 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 311 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 312 ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 313 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 314 } else { 315 PersonalityEncoding = 316 (CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 317 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 318 LSDAEncoding = (CMModel == CodeModel::Small) 319 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 320 TTypeEncoding = (CMModel == CodeModel::Small) 321 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 322 } 323 break; 324 case Triple::aarch64: 325 case Triple::aarch64_be: 326 // The small model guarantees static code/data size < 4GB, but not where it 327 // will be in memory. Most of these could end up >2GB away so even a signed 328 // pc-relative 32-bit address is insufficient, theoretically. 329 if (RelocM == Reloc::PIC_) { 330 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 331 dwarf::DW_EH_PE_sdata8; 332 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8; 333 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 334 dwarf::DW_EH_PE_sdata8; 335 } else { 336 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 337 LSDAEncoding = dwarf::DW_EH_PE_absptr; 338 TTypeEncoding = dwarf::DW_EH_PE_absptr; 339 } 340 break; 341 case Triple::mips: 342 case Triple::mipsel: 343 case Triple::mips64: 344 case Triple::mips64el: 345 // MIPS uses indirect pointer to refer personality functions, so that the 346 // eh_frame section can be read-only. DW.ref.personality will be generated 347 // for relocation. 348 PersonalityEncoding = dwarf::DW_EH_PE_indirect; 349 break; 350 case Triple::ppc64: 351 case Triple::ppc64le: 352 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 353 dwarf::DW_EH_PE_udata8; 354 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8; 355 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 356 dwarf::DW_EH_PE_udata8; 357 break; 358 case Triple::sparc: 359 if (RelocM == Reloc::PIC_) { 360 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 361 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 362 dwarf::DW_EH_PE_sdata4; 363 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 364 dwarf::DW_EH_PE_sdata4; 365 } else { 366 LSDAEncoding = dwarf::DW_EH_PE_absptr; 367 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 368 TTypeEncoding = dwarf::DW_EH_PE_absptr; 369 } 370 break; 371 case Triple::sparcv9: 372 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 373 if (RelocM == Reloc::PIC_) { 374 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 375 dwarf::DW_EH_PE_sdata4; 376 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 377 dwarf::DW_EH_PE_sdata4; 378 } else { 379 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 380 TTypeEncoding = dwarf::DW_EH_PE_absptr; 381 } 382 break; 383 case Triple::systemz: 384 // All currently-defined code models guarantee that 4-byte PC-relative 385 // values will be in range. 386 if (RelocM == Reloc::PIC_) { 387 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 388 dwarf::DW_EH_PE_sdata4; 389 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 390 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 391 dwarf::DW_EH_PE_sdata4; 392 } else { 393 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 394 LSDAEncoding = dwarf::DW_EH_PE_absptr; 395 TTypeEncoding = dwarf::DW_EH_PE_absptr; 396 } 397 break; 398 default: 399 break; 400 } 401 402 // Solaris requires different flags for .eh_frame to seemingly every other 403 // platform. 404 EHSectionType = ELF::SHT_PROGBITS; 405 EHSectionFlags = ELF::SHF_ALLOC; 406 if (T.isOSSolaris()) { 407 if (T.getArch() == Triple::x86_64) 408 EHSectionType = ELF::SHT_X86_64_UNWIND; 409 else 410 EHSectionFlags |= ELF::SHF_WRITE; 411 } 412 413 414 // ELF 415 BSSSection = Ctx->getELFSection(".bss", ELF::SHT_NOBITS, 416 ELF::SHF_WRITE | ELF::SHF_ALLOC); 417 418 TextSection = Ctx->getELFSection(".text", ELF::SHT_PROGBITS, 419 ELF::SHF_EXECINSTR | ELF::SHF_ALLOC); 420 421 DataSection = Ctx->getELFSection(".data", ELF::SHT_PROGBITS, 422 ELF::SHF_WRITE | ELF::SHF_ALLOC); 423 424 ReadOnlySection = 425 Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 426 427 TLSDataSection = 428 Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS, 429 ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE); 430 431 TLSBSSSection = Ctx->getELFSection( 432 ".tbss", ELF::SHT_NOBITS, ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE); 433 434 DataRelSection = Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS, 435 ELF::SHF_ALLOC | ELF::SHF_WRITE); 436 437 DataRelLocalSection = Ctx->getELFSection(".data.rel.local", ELF::SHT_PROGBITS, 438 ELF::SHF_ALLOC | ELF::SHF_WRITE); 439 440 DataRelROSection = Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS, 441 ELF::SHF_ALLOC | ELF::SHF_WRITE); 442 443 DataRelROLocalSection = Ctx->getELFSection( 444 ".data.rel.ro.local", ELF::SHT_PROGBITS, ELF::SHF_ALLOC | ELF::SHF_WRITE); 445 446 MergeableConst4Section = 447 Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS, 448 ELF::SHF_ALLOC | ELF::SHF_MERGE, 4, ""); 449 450 MergeableConst8Section = 451 Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS, 452 ELF::SHF_ALLOC | ELF::SHF_MERGE, 8, ""); 453 454 MergeableConst16Section = 455 Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS, 456 ELF::SHF_ALLOC | ELF::SHF_MERGE, 16, ""); 457 458 StaticCtorSection = Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS, 459 ELF::SHF_ALLOC | ELF::SHF_WRITE); 460 461 StaticDtorSection = Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS, 462 ELF::SHF_ALLOC | ELF::SHF_WRITE); 463 464 // Exception Handling Sections. 465 466 // FIXME: We're emitting LSDA info into a readonly section on ELF, even though 467 // it contains relocatable pointers. In PIC mode, this is probably a big 468 // runtime hit for C++ apps. Either the contents of the LSDA need to be 469 // adjusted or this should be a data section. 470 LSDASection = Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS, 471 ELF::SHF_ALLOC); 472 473 COFFDebugSymbolsSection = nullptr; 474 475 // Debug Info Sections. 476 DwarfAbbrevSection = 477 Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0); 478 DwarfInfoSection = Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0); 479 DwarfLineSection = Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0); 480 DwarfFrameSection = Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0); 481 DwarfPubNamesSection = 482 Ctx->getELFSection(".debug_pubnames", ELF::SHT_PROGBITS, 0); 483 DwarfPubTypesSection = 484 Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0); 485 DwarfGnuPubNamesSection = 486 Ctx->getELFSection(".debug_gnu_pubnames", ELF::SHT_PROGBITS, 0); 487 DwarfGnuPubTypesSection = 488 Ctx->getELFSection(".debug_gnu_pubtypes", ELF::SHT_PROGBITS, 0); 489 DwarfStrSection = 490 Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS, 491 ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, ""); 492 DwarfLocSection = Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0); 493 DwarfARangesSection = 494 Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0); 495 DwarfRangesSection = 496 Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0); 497 498 // DWARF5 Experimental Debug Info 499 500 // Accelerator Tables 501 DwarfAccelNamesSection = 502 Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0); 503 DwarfAccelObjCSection = 504 Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0); 505 DwarfAccelNamespaceSection = 506 Ctx->getELFSection(".apple_namespaces", ELF::SHT_PROGBITS, 0); 507 DwarfAccelTypesSection = 508 Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0); 509 510 // Fission Sections 511 DwarfInfoDWOSection = 512 Ctx->getELFSection(".debug_info.dwo", ELF::SHT_PROGBITS, 0); 513 DwarfTypesDWOSection = 514 Ctx->getELFSection(".debug_types.dwo", ELF::SHT_PROGBITS, 0); 515 DwarfAbbrevDWOSection = 516 Ctx->getELFSection(".debug_abbrev.dwo", ELF::SHT_PROGBITS, 0); 517 DwarfStrDWOSection = 518 Ctx->getELFSection(".debug_str.dwo", ELF::SHT_PROGBITS, 519 ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, ""); 520 DwarfLineDWOSection = 521 Ctx->getELFSection(".debug_line.dwo", ELF::SHT_PROGBITS, 0); 522 DwarfLocDWOSection = 523 Ctx->getELFSection(".debug_loc.dwo", ELF::SHT_PROGBITS, 0); 524 DwarfStrOffDWOSection = 525 Ctx->getELFSection(".debug_str_offsets.dwo", ELF::SHT_PROGBITS, 0); 526 DwarfAddrSection = Ctx->getELFSection(".debug_addr", ELF::SHT_PROGBITS, 0); 527 528 StackMapSection = 529 Ctx->getELFSection(".llvm_stackmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 530 } 531 532 533 void MCObjectFileInfo::InitCOFFMCObjectFileInfo(Triple T) { 534 bool IsWoA = T.getArch() == Triple::arm || T.getArch() == Triple::thumb; 535 536 CommDirectiveSupportsAlignment = true; 537 538 // COFF 539 BSSSection = 540 Ctx->getCOFFSection(".bss", 541 COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA | 542 COFF::IMAGE_SCN_MEM_READ | 543 COFF::IMAGE_SCN_MEM_WRITE, 544 SectionKind::getBSS()); 545 TextSection = 546 Ctx->getCOFFSection(".text", 547 (IsWoA ? COFF::IMAGE_SCN_MEM_16BIT 548 : (COFF::SectionCharacteristics)0) | 549 COFF::IMAGE_SCN_CNT_CODE | 550 COFF::IMAGE_SCN_MEM_EXECUTE | 551 COFF::IMAGE_SCN_MEM_READ, 552 SectionKind::getText()); 553 DataSection = 554 Ctx->getCOFFSection(".data", 555 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 556 COFF::IMAGE_SCN_MEM_READ | 557 COFF::IMAGE_SCN_MEM_WRITE, 558 SectionKind::getDataRel()); 559 ReadOnlySection = 560 Ctx->getCOFFSection(".rdata", 561 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 562 COFF::IMAGE_SCN_MEM_READ, 563 SectionKind::getReadOnly()); 564 565 if (T.isKnownWindowsMSVCEnvironment() || T.isWindowsItaniumEnvironment()) { 566 StaticCtorSection = 567 Ctx->getCOFFSection(".CRT$XCU", 568 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 569 COFF::IMAGE_SCN_MEM_READ, 570 SectionKind::getReadOnly()); 571 StaticDtorSection = 572 Ctx->getCOFFSection(".CRT$XTX", 573 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 574 COFF::IMAGE_SCN_MEM_READ, 575 SectionKind::getReadOnly()); 576 } else { 577 StaticCtorSection = 578 Ctx->getCOFFSection(".ctors", 579 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 580 COFF::IMAGE_SCN_MEM_READ | 581 COFF::IMAGE_SCN_MEM_WRITE, 582 SectionKind::getDataRel()); 583 StaticDtorSection = 584 Ctx->getCOFFSection(".dtors", 585 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 586 COFF::IMAGE_SCN_MEM_READ | 587 COFF::IMAGE_SCN_MEM_WRITE, 588 SectionKind::getDataRel()); 589 } 590 591 // FIXME: We're emitting LSDA info into a readonly section on COFF, even 592 // though it contains relocatable pointers. In PIC mode, this is probably a 593 // big runtime hit for C++ apps. Either the contents of the LSDA need to be 594 // adjusted or this should be a data section. 595 assert(T.isOSWindows() && "Windows is the only supported COFF target"); 596 if (T.getArch() == Triple::x86_64) { 597 // On Windows 64 with SEH, the LSDA is emitted into the .xdata section 598 LSDASection = 0; 599 } else { 600 LSDASection = Ctx->getCOFFSection(".gcc_except_table", 601 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 602 COFF::IMAGE_SCN_MEM_READ, 603 SectionKind::getReadOnly()); 604 } 605 606 // Debug info. 607 COFFDebugSymbolsSection = 608 Ctx->getCOFFSection(".debug$S", 609 COFF::IMAGE_SCN_MEM_DISCARDABLE | 610 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 611 COFF::IMAGE_SCN_MEM_READ, 612 SectionKind::getMetadata()); 613 614 DwarfAbbrevSection = 615 Ctx->getCOFFSection(".debug_abbrev", 616 COFF::IMAGE_SCN_MEM_DISCARDABLE | 617 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 618 COFF::IMAGE_SCN_MEM_READ, 619 SectionKind::getMetadata()); 620 DwarfInfoSection = 621 Ctx->getCOFFSection(".debug_info", 622 COFF::IMAGE_SCN_MEM_DISCARDABLE | 623 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 624 COFF::IMAGE_SCN_MEM_READ, 625 SectionKind::getMetadata()); 626 DwarfLineSection = 627 Ctx->getCOFFSection(".debug_line", 628 COFF::IMAGE_SCN_MEM_DISCARDABLE | 629 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 630 COFF::IMAGE_SCN_MEM_READ, 631 SectionKind::getMetadata()); 632 DwarfFrameSection = 633 Ctx->getCOFFSection(".debug_frame", 634 COFF::IMAGE_SCN_MEM_DISCARDABLE | 635 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 636 COFF::IMAGE_SCN_MEM_READ, 637 SectionKind::getMetadata()); 638 DwarfPubNamesSection = 639 Ctx->getCOFFSection(".debug_pubnames", 640 COFF::IMAGE_SCN_MEM_DISCARDABLE | 641 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 642 COFF::IMAGE_SCN_MEM_READ, 643 SectionKind::getMetadata()); 644 DwarfPubTypesSection = 645 Ctx->getCOFFSection(".debug_pubtypes", 646 COFF::IMAGE_SCN_MEM_DISCARDABLE | 647 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 648 COFF::IMAGE_SCN_MEM_READ, 649 SectionKind::getMetadata()); 650 DwarfGnuPubNamesSection = 651 Ctx->getCOFFSection(".debug_gnu_pubnames", 652 COFF::IMAGE_SCN_MEM_DISCARDABLE | 653 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 654 COFF::IMAGE_SCN_MEM_READ, 655 SectionKind::getMetadata()); 656 DwarfGnuPubTypesSection = 657 Ctx->getCOFFSection(".debug_gnu_pubtypes", 658 COFF::IMAGE_SCN_MEM_DISCARDABLE | 659 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 660 COFF::IMAGE_SCN_MEM_READ, 661 SectionKind::getMetadata()); 662 DwarfStrSection = 663 Ctx->getCOFFSection(".debug_str", 664 COFF::IMAGE_SCN_MEM_DISCARDABLE | 665 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 666 COFF::IMAGE_SCN_MEM_READ, 667 SectionKind::getMetadata()); 668 DwarfLocSection = 669 Ctx->getCOFFSection(".debug_loc", 670 COFF::IMAGE_SCN_MEM_DISCARDABLE | 671 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 672 COFF::IMAGE_SCN_MEM_READ, 673 SectionKind::getMetadata()); 674 DwarfARangesSection = 675 Ctx->getCOFFSection(".debug_aranges", 676 COFF::IMAGE_SCN_MEM_DISCARDABLE | 677 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 678 COFF::IMAGE_SCN_MEM_READ, 679 SectionKind::getMetadata()); 680 DwarfRangesSection = 681 Ctx->getCOFFSection(".debug_ranges", 682 COFF::IMAGE_SCN_MEM_DISCARDABLE | 683 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 684 COFF::IMAGE_SCN_MEM_READ, 685 SectionKind::getMetadata()); 686 DwarfInfoDWOSection = 687 Ctx->getCOFFSection(".debug_info.dwo", 688 COFF::IMAGE_SCN_MEM_DISCARDABLE | 689 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 690 COFF::IMAGE_SCN_MEM_READ, 691 SectionKind::getMetadata()); 692 DwarfTypesDWOSection = 693 Ctx->getCOFFSection(".debug_types.dwo", 694 COFF::IMAGE_SCN_MEM_DISCARDABLE | 695 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 696 COFF::IMAGE_SCN_MEM_READ, 697 SectionKind::getMetadata()); 698 DwarfAbbrevDWOSection = 699 Ctx->getCOFFSection(".debug_abbrev.dwo", 700 COFF::IMAGE_SCN_MEM_DISCARDABLE | 701 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 702 COFF::IMAGE_SCN_MEM_READ, 703 SectionKind::getMetadata()); 704 DwarfStrDWOSection = 705 Ctx->getCOFFSection(".debug_str.dwo", 706 COFF::IMAGE_SCN_MEM_DISCARDABLE | 707 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 708 COFF::IMAGE_SCN_MEM_READ, 709 SectionKind::getMetadata()); 710 DwarfLineDWOSection = 711 Ctx->getCOFFSection(".debug_line.dwo", 712 COFF::IMAGE_SCN_MEM_DISCARDABLE | 713 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 714 COFF::IMAGE_SCN_MEM_READ, 715 SectionKind::getMetadata()); 716 DwarfLocDWOSection = 717 Ctx->getCOFFSection(".debug_loc.dwo", 718 COFF::IMAGE_SCN_MEM_DISCARDABLE | 719 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 720 COFF::IMAGE_SCN_MEM_READ, 721 SectionKind::getMetadata()); 722 DwarfStrOffDWOSection = 723 Ctx->getCOFFSection(".debug_str_offsets.dwo", 724 COFF::IMAGE_SCN_MEM_DISCARDABLE | 725 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 726 COFF::IMAGE_SCN_MEM_READ, 727 SectionKind::getMetadata()); 728 DwarfAddrSection = 729 Ctx->getCOFFSection(".debug_addr", 730 COFF::IMAGE_SCN_MEM_DISCARDABLE | 731 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 732 COFF::IMAGE_SCN_MEM_READ, 733 SectionKind::getMetadata()); 734 DwarfAccelNamesSection = 735 Ctx->getCOFFSection(".apple_names", 736 COFF::IMAGE_SCN_MEM_DISCARDABLE | 737 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 738 COFF::IMAGE_SCN_MEM_READ, 739 SectionKind::getMetadata()); 740 DwarfAccelNamespaceSection = 741 Ctx->getCOFFSection(".apple_namespaces", 742 COFF::IMAGE_SCN_MEM_DISCARDABLE | 743 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 744 COFF::IMAGE_SCN_MEM_READ, 745 SectionKind::getMetadata()); 746 DwarfAccelTypesSection = 747 Ctx->getCOFFSection(".apple_types", 748 COFF::IMAGE_SCN_MEM_DISCARDABLE | 749 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 750 COFF::IMAGE_SCN_MEM_READ, 751 SectionKind::getMetadata()); 752 DwarfAccelObjCSection = 753 Ctx->getCOFFSection(".apple_objc", 754 COFF::IMAGE_SCN_MEM_DISCARDABLE | 755 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 756 COFF::IMAGE_SCN_MEM_READ, 757 SectionKind::getMetadata()); 758 759 DrectveSection = 760 Ctx->getCOFFSection(".drectve", 761 COFF::IMAGE_SCN_LNK_INFO | 762 COFF::IMAGE_SCN_LNK_REMOVE, 763 SectionKind::getMetadata()); 764 765 PDataSection = 766 Ctx->getCOFFSection(".pdata", 767 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 768 COFF::IMAGE_SCN_MEM_READ, 769 SectionKind::getDataRel()); 770 771 XDataSection = 772 Ctx->getCOFFSection(".xdata", 773 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 774 COFF::IMAGE_SCN_MEM_READ, 775 SectionKind::getDataRel()); 776 777 TLSDataSection = 778 Ctx->getCOFFSection(".tls$", 779 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 780 COFF::IMAGE_SCN_MEM_READ | 781 COFF::IMAGE_SCN_MEM_WRITE, 782 SectionKind::getDataRel()); 783 } 784 785 void MCObjectFileInfo::InitMCObjectFileInfo(StringRef T, Reloc::Model relocm, 786 CodeModel::Model cm, 787 MCContext &ctx) { 788 RelocM = relocm; 789 CMModel = cm; 790 Ctx = &ctx; 791 792 // Common. 793 CommDirectiveSupportsAlignment = true; 794 SupportsWeakOmittedEHFrame = true; 795 SupportsCompactUnwindWithoutEHFrame = false; 796 797 PersonalityEncoding = LSDAEncoding = FDECFIEncoding = TTypeEncoding = 798 dwarf::DW_EH_PE_absptr; 799 800 CompactUnwindDwarfEHFrameOnly = 0; 801 802 EHFrameSection = nullptr; // Created on demand. 803 CompactUnwindSection = nullptr; // Used only by selected targets. 804 DwarfAccelNamesSection = nullptr; // Used only by selected targets. 805 DwarfAccelObjCSection = nullptr; // Used only by selected targets. 806 DwarfAccelNamespaceSection = nullptr; // Used only by selected targets. 807 DwarfAccelTypesSection = nullptr; // Used only by selected targets. 808 809 TT = Triple(T); 810 811 Triple::ArchType Arch = TT.getArch(); 812 // FIXME: Checking for Arch here to filter out bogus triples such as 813 // cellspu-apple-darwin. Perhaps we should fix in Triple? 814 if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 815 Arch == Triple::arm || Arch == Triple::thumb || 816 Arch == Triple::aarch64 || 817 Arch == Triple::ppc || Arch == Triple::ppc64 || 818 Arch == Triple::UnknownArch) && 819 (TT.isOSDarwin() || TT.isOSBinFormatMachO())) { 820 Env = IsMachO; 821 InitMachOMCObjectFileInfo(TT); 822 } else if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 823 Arch == Triple::arm || Arch == Triple::thumb) && 824 (TT.isOSWindows() && TT.getObjectFormat() == Triple::COFF)) { 825 Env = IsCOFF; 826 InitCOFFMCObjectFileInfo(TT); 827 } else { 828 Env = IsELF; 829 InitELFMCObjectFileInfo(TT); 830 } 831 } 832 833 const MCSection *MCObjectFileInfo::getDwarfTypesSection(uint64_t Hash) const { 834 return Ctx->getELFSection(".debug_types", ELF::SHT_PROGBITS, ELF::SHF_GROUP, 835 0, utostr(Hash)); 836 } 837 838 void MCObjectFileInfo::InitEHFrameSection() { 839 if (Env == IsMachO) 840 EHFrameSection = 841 Ctx->getMachOSection("__TEXT", "__eh_frame", 842 MachO::S_COALESCED | 843 MachO::S_ATTR_NO_TOC | 844 MachO::S_ATTR_STRIP_STATIC_SYMS | 845 MachO::S_ATTR_LIVE_SUPPORT, 846 SectionKind::getReadOnly()); 847 else if (Env == IsELF) 848 EHFrameSection = 849 Ctx->getELFSection(".eh_frame", EHSectionType, EHSectionFlags); 850 else 851 EHFrameSection = 852 Ctx->getCOFFSection(".eh_frame", 853 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 854 COFF::IMAGE_SCN_MEM_READ | 855 COFF::IMAGE_SCN_MEM_WRITE, 856 SectionKind::getDataRel()); 857 } 858