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", MachO::S_ATTR_DEBUG, 187 SectionKind::getMetadata(), "names_begin"); 188 DwarfAccelObjCSection = 189 Ctx->getMachOSection("__DWARF", "__apple_objc", MachO::S_ATTR_DEBUG, 190 SectionKind::getMetadata(), "objc_begin"); 191 // 16 character section limit... 192 DwarfAccelNamespaceSection = 193 Ctx->getMachOSection("__DWARF", "__apple_namespac", MachO::S_ATTR_DEBUG, 194 SectionKind::getMetadata(), "namespac_begin"); 195 DwarfAccelTypesSection = 196 Ctx->getMachOSection("__DWARF", "__apple_types", MachO::S_ATTR_DEBUG, 197 SectionKind::getMetadata(), "types_begin"); 198 199 DwarfAbbrevSection = 200 Ctx->getMachOSection("__DWARF", "__debug_abbrev", MachO::S_ATTR_DEBUG, 201 SectionKind::getMetadata(), "section_abbrev"); 202 DwarfInfoSection = 203 Ctx->getMachOSection("__DWARF", "__debug_info", MachO::S_ATTR_DEBUG, 204 SectionKind::getMetadata(), "section_info"); 205 DwarfLineSection = 206 Ctx->getMachOSection("__DWARF", "__debug_line", MachO::S_ATTR_DEBUG, 207 SectionKind::getMetadata(), "section_line"); 208 DwarfFrameSection = 209 Ctx->getMachOSection("__DWARF", "__debug_frame", MachO::S_ATTR_DEBUG, 210 SectionKind::getMetadata()); 211 DwarfPubNamesSection = 212 Ctx->getMachOSection("__DWARF", "__debug_pubnames", MachO::S_ATTR_DEBUG, 213 SectionKind::getMetadata()); 214 DwarfPubTypesSection = 215 Ctx->getMachOSection("__DWARF", "__debug_pubtypes", MachO::S_ATTR_DEBUG, 216 SectionKind::getMetadata()); 217 DwarfGnuPubNamesSection = 218 Ctx->getMachOSection("__DWARF", "__debug_gnu_pubn", MachO::S_ATTR_DEBUG, 219 SectionKind::getMetadata()); 220 DwarfGnuPubTypesSection = 221 Ctx->getMachOSection("__DWARF", "__debug_gnu_pubt", MachO::S_ATTR_DEBUG, 222 SectionKind::getMetadata()); 223 DwarfStrSection = 224 Ctx->getMachOSection("__DWARF", "__debug_str", MachO::S_ATTR_DEBUG, 225 SectionKind::getMetadata(), "info_string"); 226 DwarfLocSection = 227 Ctx->getMachOSection("__DWARF", "__debug_loc", MachO::S_ATTR_DEBUG, 228 SectionKind::getMetadata(), "section_debug_loc"); 229 DwarfARangesSection = 230 Ctx->getMachOSection("__DWARF", "__debug_aranges", MachO::S_ATTR_DEBUG, 231 SectionKind::getMetadata()); 232 DwarfRangesSection = 233 Ctx->getMachOSection("__DWARF", "__debug_ranges", MachO::S_ATTR_DEBUG, 234 SectionKind::getMetadata(), "debug_range"); 235 DwarfDebugInlineSection = 236 Ctx->getMachOSection("__DWARF", "__debug_inlined", MachO::S_ATTR_DEBUG, 237 SectionKind::getMetadata()); 238 StackMapSection = Ctx->getMachOSection("__LLVM_STACKMAPS", "__llvm_stackmaps", 239 0, SectionKind::getMetadata()); 240 241 TLSExtraDataSection = TLSTLVSection; 242 } 243 244 void MCObjectFileInfo::InitELFMCObjectFileInfo(Triple T) { 245 switch (T.getArch()) { 246 case Triple::mips: 247 case Triple::mipsel: 248 FDECFIEncoding = dwarf::DW_EH_PE_sdata4; 249 break; 250 case Triple::mips64: 251 case Triple::mips64el: 252 FDECFIEncoding = dwarf::DW_EH_PE_sdata8; 253 break; 254 case Triple::x86_64: 255 FDECFIEncoding = dwarf::DW_EH_PE_pcrel | 256 ((CMModel == CodeModel::Large) ? dwarf::DW_EH_PE_sdata8 257 : dwarf::DW_EH_PE_sdata4); 258 259 break; 260 default: 261 FDECFIEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 262 break; 263 } 264 265 switch (T.getArch()) { 266 case Triple::arm: 267 case Triple::armeb: 268 case Triple::thumb: 269 case Triple::thumbeb: 270 if (Ctx->getAsmInfo()->getExceptionHandlingType() == ExceptionHandling::ARM) 271 break; 272 // Fallthrough if not using EHABI 273 case Triple::ppc: 274 case Triple::x86: 275 PersonalityEncoding = (RelocM == Reloc::PIC_) 276 ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 277 : dwarf::DW_EH_PE_absptr; 278 LSDAEncoding = (RelocM == Reloc::PIC_) 279 ? dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 280 : dwarf::DW_EH_PE_absptr; 281 TTypeEncoding = (RelocM == Reloc::PIC_) 282 ? dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 283 : dwarf::DW_EH_PE_absptr; 284 break; 285 case Triple::x86_64: 286 if (RelocM == Reloc::PIC_) { 287 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 288 ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 289 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 290 LSDAEncoding = dwarf::DW_EH_PE_pcrel | 291 (CMModel == CodeModel::Small 292 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 293 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 294 ((CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 295 ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8); 296 } else { 297 PersonalityEncoding = 298 (CMModel == CodeModel::Small || CMModel == CodeModel::Medium) 299 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 300 LSDAEncoding = (CMModel == CodeModel::Small) 301 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 302 TTypeEncoding = (CMModel == CodeModel::Small) 303 ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr; 304 } 305 break; 306 case Triple::aarch64: 307 case Triple::aarch64_be: 308 // The small model guarantees static code/data size < 4GB, but not where it 309 // will be in memory. Most of these could end up >2GB away so even a signed 310 // pc-relative 32-bit address is insufficient, theoretically. 311 if (RelocM == Reloc::PIC_) { 312 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 313 dwarf::DW_EH_PE_sdata8; 314 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8; 315 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 316 dwarf::DW_EH_PE_sdata8; 317 } else { 318 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 319 LSDAEncoding = dwarf::DW_EH_PE_absptr; 320 TTypeEncoding = dwarf::DW_EH_PE_absptr; 321 } 322 break; 323 case Triple::mips: 324 case Triple::mipsel: 325 case Triple::mips64: 326 case Triple::mips64el: 327 // MIPS uses indirect pointer to refer personality functions, so that the 328 // eh_frame section can be read-only. DW.ref.personality will be generated 329 // for relocation. 330 PersonalityEncoding = dwarf::DW_EH_PE_indirect; 331 break; 332 case Triple::ppc64: 333 case Triple::ppc64le: 334 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 335 dwarf::DW_EH_PE_udata8; 336 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8; 337 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 338 dwarf::DW_EH_PE_udata8; 339 break; 340 case Triple::sparcel: 341 case Triple::sparc: 342 if (RelocM == Reloc::PIC_) { 343 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 344 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 345 dwarf::DW_EH_PE_sdata4; 346 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 347 dwarf::DW_EH_PE_sdata4; 348 } else { 349 LSDAEncoding = dwarf::DW_EH_PE_absptr; 350 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 351 TTypeEncoding = dwarf::DW_EH_PE_absptr; 352 } 353 break; 354 case Triple::sparcv9: 355 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 356 if (RelocM == Reloc::PIC_) { 357 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 358 dwarf::DW_EH_PE_sdata4; 359 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 360 dwarf::DW_EH_PE_sdata4; 361 } else { 362 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 363 TTypeEncoding = dwarf::DW_EH_PE_absptr; 364 } 365 break; 366 case Triple::systemz: 367 // All currently-defined code models guarantee that 4-byte PC-relative 368 // values will be in range. 369 if (RelocM == Reloc::PIC_) { 370 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 371 dwarf::DW_EH_PE_sdata4; 372 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 373 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 374 dwarf::DW_EH_PE_sdata4; 375 } else { 376 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 377 LSDAEncoding = dwarf::DW_EH_PE_absptr; 378 TTypeEncoding = dwarf::DW_EH_PE_absptr; 379 } 380 break; 381 default: 382 break; 383 } 384 385 // Solaris requires different flags for .eh_frame to seemingly every other 386 // platform. 387 EHSectionType = ELF::SHT_PROGBITS; 388 EHSectionFlags = ELF::SHF_ALLOC; 389 if (T.isOSSolaris()) { 390 if (T.getArch() == Triple::x86_64) 391 EHSectionType = ELF::SHT_X86_64_UNWIND; 392 else 393 EHSectionFlags |= ELF::SHF_WRITE; 394 } 395 396 397 // ELF 398 BSSSection = Ctx->getELFSection(".bss", ELF::SHT_NOBITS, 399 ELF::SHF_WRITE | ELF::SHF_ALLOC); 400 401 TextSection = Ctx->getELFSection(".text", ELF::SHT_PROGBITS, 402 ELF::SHF_EXECINSTR | ELF::SHF_ALLOC); 403 404 DataSection = Ctx->getELFSection(".data", ELF::SHT_PROGBITS, 405 ELF::SHF_WRITE | ELF::SHF_ALLOC); 406 407 ReadOnlySection = 408 Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 409 410 TLSDataSection = 411 Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS, 412 ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE); 413 414 TLSBSSSection = Ctx->getELFSection( 415 ".tbss", ELF::SHT_NOBITS, ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE); 416 417 DataRelSection = Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS, 418 ELF::SHF_ALLOC | ELF::SHF_WRITE); 419 420 DataRelLocalSection = Ctx->getELFSection(".data.rel.local", ELF::SHT_PROGBITS, 421 ELF::SHF_ALLOC | ELF::SHF_WRITE); 422 423 DataRelROSection = Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS, 424 ELF::SHF_ALLOC | ELF::SHF_WRITE); 425 426 DataRelROLocalSection = Ctx->getELFSection( 427 ".data.rel.ro.local", ELF::SHT_PROGBITS, ELF::SHF_ALLOC | ELF::SHF_WRITE); 428 429 MergeableConst4Section = 430 Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS, 431 ELF::SHF_ALLOC | ELF::SHF_MERGE, 4, ""); 432 433 MergeableConst8Section = 434 Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS, 435 ELF::SHF_ALLOC | ELF::SHF_MERGE, 8, ""); 436 437 MergeableConst16Section = 438 Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS, 439 ELF::SHF_ALLOC | ELF::SHF_MERGE, 16, ""); 440 441 StaticCtorSection = Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS, 442 ELF::SHF_ALLOC | ELF::SHF_WRITE); 443 444 StaticDtorSection = Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS, 445 ELF::SHF_ALLOC | ELF::SHF_WRITE); 446 447 // Exception Handling Sections. 448 449 // FIXME: We're emitting LSDA info into a readonly section on ELF, even though 450 // it contains relocatable pointers. In PIC mode, this is probably a big 451 // runtime hit for C++ apps. Either the contents of the LSDA need to be 452 // adjusted or this should be a data section. 453 LSDASection = Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS, 454 ELF::SHF_ALLOC); 455 456 COFFDebugSymbolsSection = nullptr; 457 458 // Debug Info Sections. 459 DwarfAbbrevSection = Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0, 460 "section_abbrev"); 461 DwarfInfoSection = 462 Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0, "section_info"); 463 DwarfLineSection = Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0); 464 DwarfFrameSection = Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0); 465 DwarfPubNamesSection = 466 Ctx->getELFSection(".debug_pubnames", ELF::SHT_PROGBITS, 0); 467 DwarfPubTypesSection = 468 Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0); 469 DwarfGnuPubNamesSection = 470 Ctx->getELFSection(".debug_gnu_pubnames", ELF::SHT_PROGBITS, 0); 471 DwarfGnuPubTypesSection = 472 Ctx->getELFSection(".debug_gnu_pubtypes", ELF::SHT_PROGBITS, 0); 473 DwarfStrSection = 474 Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS, 475 ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, ""); 476 DwarfLocSection = Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0); 477 DwarfARangesSection = 478 Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0); 479 DwarfRangesSection = 480 Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0, "debug_range"); 481 482 // DWARF5 Experimental Debug Info 483 484 // Accelerator Tables 485 DwarfAccelNamesSection = 486 Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0, "names_begin"); 487 DwarfAccelObjCSection = 488 Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0, "objc_begin"); 489 DwarfAccelNamespaceSection = Ctx->getELFSection( 490 ".apple_namespaces", ELF::SHT_PROGBITS, 0, "namespac_begin"); 491 DwarfAccelTypesSection = 492 Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0, "types_begin"); 493 494 // Fission Sections 495 DwarfInfoDWOSection = 496 Ctx->getELFSection(".debug_info.dwo", ELF::SHT_PROGBITS, 0); 497 DwarfTypesDWOSection = 498 Ctx->getELFSection(".debug_types.dwo", ELF::SHT_PROGBITS, 0); 499 DwarfAbbrevDWOSection = 500 Ctx->getELFSection(".debug_abbrev.dwo", ELF::SHT_PROGBITS, 0); 501 DwarfStrDWOSection = 502 Ctx->getELFSection(".debug_str.dwo", ELF::SHT_PROGBITS, 503 ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, ""); 504 DwarfLineDWOSection = 505 Ctx->getELFSection(".debug_line.dwo", ELF::SHT_PROGBITS, 0); 506 DwarfLocDWOSection = 507 Ctx->getELFSection(".debug_loc.dwo", ELF::SHT_PROGBITS, 0, "skel_loc"); 508 DwarfStrOffDWOSection = 509 Ctx->getELFSection(".debug_str_offsets.dwo", ELF::SHT_PROGBITS, 0); 510 DwarfAddrSection = 511 Ctx->getELFSection(".debug_addr", ELF::SHT_PROGBITS, 0, "addr_sec"); 512 513 StackMapSection = 514 Ctx->getELFSection(".llvm_stackmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 515 } 516 517 void MCObjectFileInfo::InitCOFFMCObjectFileInfo(Triple T) { 518 bool IsWoA = T.getArch() == Triple::arm || T.getArch() == Triple::thumb; 519 520 CommDirectiveSupportsAlignment = true; 521 522 // COFF 523 BSSSection = Ctx->getCOFFSection( 524 ".bss", COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA | 525 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 526 SectionKind::getBSS()); 527 TextSection = Ctx->getCOFFSection( 528 ".text", 529 (IsWoA ? COFF::IMAGE_SCN_MEM_16BIT : (COFF::SectionCharacteristics)0) | 530 COFF::IMAGE_SCN_CNT_CODE | COFF::IMAGE_SCN_MEM_EXECUTE | 531 COFF::IMAGE_SCN_MEM_READ, 532 SectionKind::getText()); 533 DataSection = Ctx->getCOFFSection( 534 ".data", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ | 535 COFF::IMAGE_SCN_MEM_WRITE, 536 SectionKind::getDataRel()); 537 ReadOnlySection = Ctx->getCOFFSection( 538 ".rdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 539 SectionKind::getReadOnly()); 540 541 if (T.isKnownWindowsMSVCEnvironment() || T.isWindowsItaniumEnvironment()) { 542 StaticCtorSection = 543 Ctx->getCOFFSection(".CRT$XCU", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 544 COFF::IMAGE_SCN_MEM_READ, 545 SectionKind::getReadOnly()); 546 StaticDtorSection = 547 Ctx->getCOFFSection(".CRT$XTX", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 548 COFF::IMAGE_SCN_MEM_READ, 549 SectionKind::getReadOnly()); 550 } else { 551 StaticCtorSection = Ctx->getCOFFSection( 552 ".ctors", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 553 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 554 SectionKind::getDataRel()); 555 StaticDtorSection = Ctx->getCOFFSection( 556 ".dtors", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 557 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 558 SectionKind::getDataRel()); 559 } 560 561 // FIXME: We're emitting LSDA info into a readonly section on COFF, even 562 // though it contains relocatable pointers. In PIC mode, this is probably a 563 // big runtime hit for C++ apps. Either the contents of the LSDA need to be 564 // adjusted or this should be a data section. 565 assert(T.isOSWindows() && "Windows is the only supported COFF target"); 566 if (T.getArch() == Triple::x86_64) { 567 // On Windows 64 with SEH, the LSDA is emitted into the .xdata section 568 LSDASection = 0; 569 } else { 570 LSDASection = Ctx->getCOFFSection(".gcc_except_table", 571 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 572 COFF::IMAGE_SCN_MEM_READ, 573 SectionKind::getReadOnly()); 574 } 575 576 // Debug info. 577 COFFDebugSymbolsSection = 578 Ctx->getCOFFSection(".debug$S", COFF::IMAGE_SCN_MEM_DISCARDABLE | 579 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 580 COFF::IMAGE_SCN_MEM_READ, 581 SectionKind::getMetadata()); 582 583 DwarfAbbrevSection = Ctx->getCOFFSection( 584 ".debug_abbrev", 585 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 586 COFF::IMAGE_SCN_MEM_READ, 587 SectionKind::getMetadata(), "section_abbrev"); 588 DwarfInfoSection = Ctx->getCOFFSection( 589 ".debug_info", 590 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 591 COFF::IMAGE_SCN_MEM_READ, 592 SectionKind::getMetadata(), "section_info"); 593 DwarfLineSection = Ctx->getCOFFSection( 594 ".debug_line", 595 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 596 COFF::IMAGE_SCN_MEM_READ, 597 SectionKind::getMetadata(), "section_line"); 598 599 DwarfFrameSection = Ctx->getCOFFSection( 600 ".debug_frame", 601 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 602 COFF::IMAGE_SCN_MEM_READ, 603 SectionKind::getMetadata()); 604 DwarfPubNamesSection = Ctx->getCOFFSection( 605 ".debug_pubnames", 606 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 607 COFF::IMAGE_SCN_MEM_READ, 608 SectionKind::getMetadata()); 609 DwarfPubTypesSection = Ctx->getCOFFSection( 610 ".debug_pubtypes", 611 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 612 COFF::IMAGE_SCN_MEM_READ, 613 SectionKind::getMetadata()); 614 DwarfGnuPubNamesSection = Ctx->getCOFFSection( 615 ".debug_gnu_pubnames", 616 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 617 COFF::IMAGE_SCN_MEM_READ, 618 SectionKind::getMetadata()); 619 DwarfGnuPubTypesSection = Ctx->getCOFFSection( 620 ".debug_gnu_pubtypes", 621 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 622 COFF::IMAGE_SCN_MEM_READ, 623 SectionKind::getMetadata()); 624 DwarfStrSection = Ctx->getCOFFSection( 625 ".debug_str", 626 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 627 COFF::IMAGE_SCN_MEM_READ, 628 SectionKind::getMetadata(), "info_string"); 629 DwarfLocSection = Ctx->getCOFFSection( 630 ".debug_loc", 631 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 632 COFF::IMAGE_SCN_MEM_READ, 633 SectionKind::getMetadata(), "section_debug_loc"); 634 DwarfARangesSection = Ctx->getCOFFSection( 635 ".debug_aranges", 636 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 637 COFF::IMAGE_SCN_MEM_READ, 638 SectionKind::getMetadata()); 639 DwarfRangesSection = Ctx->getCOFFSection( 640 ".debug_ranges", 641 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 642 COFF::IMAGE_SCN_MEM_READ, 643 SectionKind::getMetadata(), "debug_range"); 644 DwarfInfoDWOSection = Ctx->getCOFFSection( 645 ".debug_info.dwo", 646 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 647 COFF::IMAGE_SCN_MEM_READ, 648 SectionKind::getMetadata(), "section_info_dwo"); 649 DwarfTypesDWOSection = Ctx->getCOFFSection( 650 ".debug_types.dwo", 651 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 652 COFF::IMAGE_SCN_MEM_READ, 653 SectionKind::getMetadata(), "section_types_dwo"); 654 DwarfAbbrevDWOSection = Ctx->getCOFFSection( 655 ".debug_abbrev.dwo", 656 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 657 COFF::IMAGE_SCN_MEM_READ, 658 SectionKind::getMetadata(), "section_abbrev_dwo"); 659 DwarfStrDWOSection = Ctx->getCOFFSection( 660 ".debug_str.dwo", 661 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 662 COFF::IMAGE_SCN_MEM_READ, 663 SectionKind::getMetadata(), "skel_string"); 664 DwarfLineDWOSection = Ctx->getCOFFSection( 665 ".debug_line.dwo", 666 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 667 COFF::IMAGE_SCN_MEM_READ, 668 SectionKind::getMetadata()); 669 DwarfLocDWOSection = Ctx->getCOFFSection( 670 ".debug_loc.dwo", 671 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 672 COFF::IMAGE_SCN_MEM_READ, 673 SectionKind::getMetadata(), "skel_loc"); 674 DwarfStrOffDWOSection = Ctx->getCOFFSection( 675 ".debug_str_offsets.dwo", 676 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 677 COFF::IMAGE_SCN_MEM_READ, 678 SectionKind::getMetadata()); 679 DwarfAddrSection = Ctx->getCOFFSection( 680 ".debug_addr", 681 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 682 COFF::IMAGE_SCN_MEM_READ, 683 SectionKind::getMetadata(), "addr_sec"); 684 DwarfAccelNamesSection = Ctx->getCOFFSection( 685 ".apple_names", 686 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 687 COFF::IMAGE_SCN_MEM_READ, 688 SectionKind::getMetadata(), "names_begin"); 689 DwarfAccelNamespaceSection = Ctx->getCOFFSection( 690 ".apple_namespaces", 691 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 692 COFF::IMAGE_SCN_MEM_READ, 693 SectionKind::getMetadata(), "namespac_begin"); 694 DwarfAccelTypesSection = Ctx->getCOFFSection( 695 ".apple_types", 696 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 697 COFF::IMAGE_SCN_MEM_READ, 698 SectionKind::getMetadata(), "types_begin"); 699 DwarfAccelObjCSection = Ctx->getCOFFSection( 700 ".apple_objc", 701 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 702 COFF::IMAGE_SCN_MEM_READ, 703 SectionKind::getMetadata(), "objc_begin"); 704 705 DrectveSection = Ctx->getCOFFSection( 706 ".drectve", COFF::IMAGE_SCN_LNK_INFO | COFF::IMAGE_SCN_LNK_REMOVE, 707 SectionKind::getMetadata()); 708 709 PDataSection = Ctx->getCOFFSection( 710 ".pdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 711 SectionKind::getDataRel()); 712 713 XDataSection = Ctx->getCOFFSection( 714 ".xdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 715 SectionKind::getDataRel()); 716 717 TLSDataSection = Ctx->getCOFFSection( 718 ".tls$", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ | 719 COFF::IMAGE_SCN_MEM_WRITE, 720 SectionKind::getDataRel()); 721 } 722 723 void MCObjectFileInfo::InitMCObjectFileInfo(StringRef T, Reloc::Model relocm, 724 CodeModel::Model cm, 725 MCContext &ctx) { 726 RelocM = relocm; 727 CMModel = cm; 728 Ctx = &ctx; 729 730 // Common. 731 CommDirectiveSupportsAlignment = true; 732 SupportsWeakOmittedEHFrame = true; 733 SupportsCompactUnwindWithoutEHFrame = false; 734 735 PersonalityEncoding = LSDAEncoding = FDECFIEncoding = TTypeEncoding = 736 dwarf::DW_EH_PE_absptr; 737 738 CompactUnwindDwarfEHFrameOnly = 0; 739 740 EHFrameSection = nullptr; // Created on demand. 741 CompactUnwindSection = nullptr; // Used only by selected targets. 742 DwarfAccelNamesSection = nullptr; // Used only by selected targets. 743 DwarfAccelObjCSection = nullptr; // Used only by selected targets. 744 DwarfAccelNamespaceSection = nullptr; // Used only by selected targets. 745 DwarfAccelTypesSection = nullptr; // Used only by selected targets. 746 747 TT = Triple(T); 748 749 Triple::ArchType Arch = TT.getArch(); 750 // FIXME: Checking for Arch here to filter out bogus triples such as 751 // cellspu-apple-darwin. Perhaps we should fix in Triple? 752 if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 753 Arch == Triple::arm || Arch == Triple::thumb || 754 Arch == Triple::aarch64 || 755 Arch == Triple::ppc || Arch == Triple::ppc64 || 756 Arch == Triple::UnknownArch) && 757 TT.isOSBinFormatMachO()) { 758 Env = IsMachO; 759 InitMachOMCObjectFileInfo(TT); 760 } else if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 761 Arch == Triple::arm || Arch == Triple::thumb) && 762 (TT.isOSWindows() && TT.getObjectFormat() == Triple::COFF)) { 763 Env = IsCOFF; 764 InitCOFFMCObjectFileInfo(TT); 765 } else { 766 Env = IsELF; 767 InitELFMCObjectFileInfo(TT); 768 } 769 } 770 771 const MCSection *MCObjectFileInfo::getDwarfTypesSection(uint64_t Hash) const { 772 return Ctx->getELFSection(".debug_types", ELF::SHT_PROGBITS, ELF::SHF_GROUP, 773 0, utostr(Hash)); 774 } 775 776 void MCObjectFileInfo::InitEHFrameSection() { 777 if (Env == IsMachO) 778 EHFrameSection = 779 Ctx->getMachOSection("__TEXT", "__eh_frame", 780 MachO::S_COALESCED | 781 MachO::S_ATTR_NO_TOC | 782 MachO::S_ATTR_STRIP_STATIC_SYMS | 783 MachO::S_ATTR_LIVE_SUPPORT, 784 SectionKind::getReadOnly()); 785 else if (Env == IsELF) 786 EHFrameSection = 787 Ctx->getELFSection(".eh_frame", EHSectionType, EHSectionFlags); 788 else 789 EHFrameSection = 790 Ctx->getCOFFSection(".eh_frame", 791 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 792 COFF::IMAGE_SCN_MEM_READ | 793 COFF::IMAGE_SCN_MEM_WRITE, 794 SectionKind::getDataRel()); 795 } 796