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 and types, so 328 // that the eh_frame section can be read-only. DW.ref.personality will be 329 // generated for relocation. 330 PersonalityEncoding = dwarf::DW_EH_PE_indirect; 331 // FIXME: The N64 ABI probably ought to use DW_EH_PE_sdata8 but we can't 332 // identify N64 from just a triple. 333 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 334 dwarf::DW_EH_PE_sdata4; 335 // We don't support PC-relative LSDA references in GAS so we use the default 336 // DW_EH_PE_absptr for those. 337 break; 338 case Triple::ppc64: 339 case Triple::ppc64le: 340 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 341 dwarf::DW_EH_PE_udata8; 342 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8; 343 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 344 dwarf::DW_EH_PE_udata8; 345 break; 346 case Triple::sparcel: 347 case Triple::sparc: 348 if (RelocM == Reloc::PIC_) { 349 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 350 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 351 dwarf::DW_EH_PE_sdata4; 352 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 353 dwarf::DW_EH_PE_sdata4; 354 } else { 355 LSDAEncoding = dwarf::DW_EH_PE_absptr; 356 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 357 TTypeEncoding = dwarf::DW_EH_PE_absptr; 358 } 359 break; 360 case Triple::sparcv9: 361 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 362 if (RelocM == Reloc::PIC_) { 363 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 364 dwarf::DW_EH_PE_sdata4; 365 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 366 dwarf::DW_EH_PE_sdata4; 367 } else { 368 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 369 TTypeEncoding = dwarf::DW_EH_PE_absptr; 370 } 371 break; 372 case Triple::systemz: 373 // All currently-defined code models guarantee that 4-byte PC-relative 374 // values will be in range. 375 if (RelocM == Reloc::PIC_) { 376 PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 377 dwarf::DW_EH_PE_sdata4; 378 LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4; 379 TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel | 380 dwarf::DW_EH_PE_sdata4; 381 } else { 382 PersonalityEncoding = dwarf::DW_EH_PE_absptr; 383 LSDAEncoding = dwarf::DW_EH_PE_absptr; 384 TTypeEncoding = dwarf::DW_EH_PE_absptr; 385 } 386 break; 387 default: 388 break; 389 } 390 391 // Solaris requires different flags for .eh_frame to seemingly every other 392 // platform. 393 EHSectionType = ELF::SHT_PROGBITS; 394 EHSectionFlags = ELF::SHF_ALLOC; 395 if (T.isOSSolaris()) { 396 if (T.getArch() == Triple::x86_64) 397 EHSectionType = ELF::SHT_X86_64_UNWIND; 398 else 399 EHSectionFlags |= ELF::SHF_WRITE; 400 } 401 402 403 // ELF 404 BSSSection = Ctx->getELFSection(".bss", ELF::SHT_NOBITS, 405 ELF::SHF_WRITE | ELF::SHF_ALLOC); 406 407 TextSection = Ctx->getELFSection(".text", ELF::SHT_PROGBITS, 408 ELF::SHF_EXECINSTR | ELF::SHF_ALLOC); 409 410 DataSection = Ctx->getELFSection(".data", ELF::SHT_PROGBITS, 411 ELF::SHF_WRITE | ELF::SHF_ALLOC); 412 413 ReadOnlySection = 414 Ctx->getELFSection(".rodata", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 415 416 TLSDataSection = 417 Ctx->getELFSection(".tdata", ELF::SHT_PROGBITS, 418 ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE); 419 420 TLSBSSSection = Ctx->getELFSection( 421 ".tbss", ELF::SHT_NOBITS, ELF::SHF_ALLOC | ELF::SHF_TLS | ELF::SHF_WRITE); 422 423 DataRelSection = Ctx->getELFSection(".data.rel", ELF::SHT_PROGBITS, 424 ELF::SHF_ALLOC | ELF::SHF_WRITE); 425 426 DataRelLocalSection = Ctx->getELFSection(".data.rel.local", ELF::SHT_PROGBITS, 427 ELF::SHF_ALLOC | ELF::SHF_WRITE); 428 429 DataRelROSection = Ctx->getELFSection(".data.rel.ro", ELF::SHT_PROGBITS, 430 ELF::SHF_ALLOC | ELF::SHF_WRITE); 431 432 DataRelROLocalSection = Ctx->getELFSection( 433 ".data.rel.ro.local", ELF::SHT_PROGBITS, ELF::SHF_ALLOC | ELF::SHF_WRITE); 434 435 MergeableConst4Section = 436 Ctx->getELFSection(".rodata.cst4", ELF::SHT_PROGBITS, 437 ELF::SHF_ALLOC | ELF::SHF_MERGE, 4, ""); 438 439 MergeableConst8Section = 440 Ctx->getELFSection(".rodata.cst8", ELF::SHT_PROGBITS, 441 ELF::SHF_ALLOC | ELF::SHF_MERGE, 8, ""); 442 443 MergeableConst16Section = 444 Ctx->getELFSection(".rodata.cst16", ELF::SHT_PROGBITS, 445 ELF::SHF_ALLOC | ELF::SHF_MERGE, 16, ""); 446 447 StaticCtorSection = Ctx->getELFSection(".ctors", ELF::SHT_PROGBITS, 448 ELF::SHF_ALLOC | ELF::SHF_WRITE); 449 450 StaticDtorSection = Ctx->getELFSection(".dtors", ELF::SHT_PROGBITS, 451 ELF::SHF_ALLOC | ELF::SHF_WRITE); 452 453 // Exception Handling Sections. 454 455 // FIXME: We're emitting LSDA info into a readonly section on ELF, even though 456 // it contains relocatable pointers. In PIC mode, this is probably a big 457 // runtime hit for C++ apps. Either the contents of the LSDA need to be 458 // adjusted or this should be a data section. 459 LSDASection = Ctx->getELFSection(".gcc_except_table", ELF::SHT_PROGBITS, 460 ELF::SHF_ALLOC); 461 462 COFFDebugSymbolsSection = nullptr; 463 464 // Debug Info Sections. 465 DwarfAbbrevSection = Ctx->getELFSection(".debug_abbrev", ELF::SHT_PROGBITS, 0, 466 "section_abbrev"); 467 DwarfInfoSection = 468 Ctx->getELFSection(".debug_info", ELF::SHT_PROGBITS, 0, "section_info"); 469 DwarfLineSection = Ctx->getELFSection(".debug_line", ELF::SHT_PROGBITS, 0); 470 DwarfFrameSection = Ctx->getELFSection(".debug_frame", ELF::SHT_PROGBITS, 0); 471 DwarfPubNamesSection = 472 Ctx->getELFSection(".debug_pubnames", ELF::SHT_PROGBITS, 0); 473 DwarfPubTypesSection = 474 Ctx->getELFSection(".debug_pubtypes", ELF::SHT_PROGBITS, 0); 475 DwarfGnuPubNamesSection = 476 Ctx->getELFSection(".debug_gnu_pubnames", ELF::SHT_PROGBITS, 0); 477 DwarfGnuPubTypesSection = 478 Ctx->getELFSection(".debug_gnu_pubtypes", ELF::SHT_PROGBITS, 0); 479 DwarfStrSection = 480 Ctx->getELFSection(".debug_str", ELF::SHT_PROGBITS, 481 ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, ""); 482 DwarfLocSection = Ctx->getELFSection(".debug_loc", ELF::SHT_PROGBITS, 0); 483 DwarfARangesSection = 484 Ctx->getELFSection(".debug_aranges", ELF::SHT_PROGBITS, 0); 485 DwarfRangesSection = 486 Ctx->getELFSection(".debug_ranges", ELF::SHT_PROGBITS, 0, "debug_range"); 487 488 // DWARF5 Experimental Debug Info 489 490 // Accelerator Tables 491 DwarfAccelNamesSection = 492 Ctx->getELFSection(".apple_names", ELF::SHT_PROGBITS, 0, "names_begin"); 493 DwarfAccelObjCSection = 494 Ctx->getELFSection(".apple_objc", ELF::SHT_PROGBITS, 0, "objc_begin"); 495 DwarfAccelNamespaceSection = Ctx->getELFSection( 496 ".apple_namespaces", ELF::SHT_PROGBITS, 0, "namespac_begin"); 497 DwarfAccelTypesSection = 498 Ctx->getELFSection(".apple_types", ELF::SHT_PROGBITS, 0, "types_begin"); 499 500 // Fission Sections 501 DwarfInfoDWOSection = 502 Ctx->getELFSection(".debug_info.dwo", ELF::SHT_PROGBITS, 0); 503 DwarfTypesDWOSection = 504 Ctx->getELFSection(".debug_types.dwo", ELF::SHT_PROGBITS, 0); 505 DwarfAbbrevDWOSection = 506 Ctx->getELFSection(".debug_abbrev.dwo", ELF::SHT_PROGBITS, 0); 507 DwarfStrDWOSection = 508 Ctx->getELFSection(".debug_str.dwo", ELF::SHT_PROGBITS, 509 ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, ""); 510 DwarfLineDWOSection = 511 Ctx->getELFSection(".debug_line.dwo", ELF::SHT_PROGBITS, 0); 512 DwarfLocDWOSection = 513 Ctx->getELFSection(".debug_loc.dwo", ELF::SHT_PROGBITS, 0, "skel_loc"); 514 DwarfStrOffDWOSection = 515 Ctx->getELFSection(".debug_str_offsets.dwo", ELF::SHT_PROGBITS, 0); 516 DwarfAddrSection = 517 Ctx->getELFSection(".debug_addr", ELF::SHT_PROGBITS, 0, "addr_sec"); 518 519 StackMapSection = 520 Ctx->getELFSection(".llvm_stackmaps", ELF::SHT_PROGBITS, ELF::SHF_ALLOC); 521 } 522 523 void MCObjectFileInfo::initCOFFMCObjectFileInfo(Triple T) { 524 bool IsWoA = T.getArch() == Triple::arm || T.getArch() == Triple::thumb; 525 526 CommDirectiveSupportsAlignment = true; 527 528 // COFF 529 BSSSection = Ctx->getCOFFSection( 530 ".bss", COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA | 531 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 532 SectionKind::getBSS()); 533 TextSection = Ctx->getCOFFSection( 534 ".text", 535 (IsWoA ? COFF::IMAGE_SCN_MEM_16BIT : (COFF::SectionCharacteristics)0) | 536 COFF::IMAGE_SCN_CNT_CODE | COFF::IMAGE_SCN_MEM_EXECUTE | 537 COFF::IMAGE_SCN_MEM_READ, 538 SectionKind::getText()); 539 DataSection = Ctx->getCOFFSection( 540 ".data", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ | 541 COFF::IMAGE_SCN_MEM_WRITE, 542 SectionKind::getDataRel()); 543 ReadOnlySection = Ctx->getCOFFSection( 544 ".rdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 545 SectionKind::getReadOnly()); 546 547 if (T.isKnownWindowsMSVCEnvironment() || T.isWindowsItaniumEnvironment()) { 548 StaticCtorSection = 549 Ctx->getCOFFSection(".CRT$XCU", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 550 COFF::IMAGE_SCN_MEM_READ, 551 SectionKind::getReadOnly()); 552 StaticDtorSection = 553 Ctx->getCOFFSection(".CRT$XTX", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 554 COFF::IMAGE_SCN_MEM_READ, 555 SectionKind::getReadOnly()); 556 } else { 557 StaticCtorSection = Ctx->getCOFFSection( 558 ".ctors", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 559 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 560 SectionKind::getDataRel()); 561 StaticDtorSection = Ctx->getCOFFSection( 562 ".dtors", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 563 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE, 564 SectionKind::getDataRel()); 565 } 566 567 // FIXME: We're emitting LSDA info into a readonly section on COFF, even 568 // though it contains relocatable pointers. In PIC mode, this is probably a 569 // big runtime hit for C++ apps. Either the contents of the LSDA need to be 570 // adjusted or this should be a data section. 571 assert(T.isOSWindows() && "Windows is the only supported COFF target"); 572 if (T.getArch() == Triple::x86_64) { 573 // On Windows 64 with SEH, the LSDA is emitted into the .xdata section 574 LSDASection = 0; 575 } else { 576 LSDASection = Ctx->getCOFFSection(".gcc_except_table", 577 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 578 COFF::IMAGE_SCN_MEM_READ, 579 SectionKind::getReadOnly()); 580 } 581 582 // Debug info. 583 COFFDebugSymbolsSection = 584 Ctx->getCOFFSection(".debug$S", COFF::IMAGE_SCN_MEM_DISCARDABLE | 585 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 586 COFF::IMAGE_SCN_MEM_READ, 587 SectionKind::getMetadata()); 588 589 DwarfAbbrevSection = Ctx->getCOFFSection( 590 ".debug_abbrev", 591 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 592 COFF::IMAGE_SCN_MEM_READ, 593 SectionKind::getMetadata(), "section_abbrev"); 594 DwarfInfoSection = Ctx->getCOFFSection( 595 ".debug_info", 596 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 597 COFF::IMAGE_SCN_MEM_READ, 598 SectionKind::getMetadata(), "section_info"); 599 DwarfLineSection = Ctx->getCOFFSection( 600 ".debug_line", 601 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 602 COFF::IMAGE_SCN_MEM_READ, 603 SectionKind::getMetadata(), "section_line"); 604 605 DwarfFrameSection = Ctx->getCOFFSection( 606 ".debug_frame", 607 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 608 COFF::IMAGE_SCN_MEM_READ, 609 SectionKind::getMetadata()); 610 DwarfPubNamesSection = Ctx->getCOFFSection( 611 ".debug_pubnames", 612 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 613 COFF::IMAGE_SCN_MEM_READ, 614 SectionKind::getMetadata()); 615 DwarfPubTypesSection = Ctx->getCOFFSection( 616 ".debug_pubtypes", 617 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 618 COFF::IMAGE_SCN_MEM_READ, 619 SectionKind::getMetadata()); 620 DwarfGnuPubNamesSection = Ctx->getCOFFSection( 621 ".debug_gnu_pubnames", 622 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 623 COFF::IMAGE_SCN_MEM_READ, 624 SectionKind::getMetadata()); 625 DwarfGnuPubTypesSection = Ctx->getCOFFSection( 626 ".debug_gnu_pubtypes", 627 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 628 COFF::IMAGE_SCN_MEM_READ, 629 SectionKind::getMetadata()); 630 DwarfStrSection = Ctx->getCOFFSection( 631 ".debug_str", 632 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 633 COFF::IMAGE_SCN_MEM_READ, 634 SectionKind::getMetadata(), "info_string"); 635 DwarfLocSection = Ctx->getCOFFSection( 636 ".debug_loc", 637 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 638 COFF::IMAGE_SCN_MEM_READ, 639 SectionKind::getMetadata(), "section_debug_loc"); 640 DwarfARangesSection = Ctx->getCOFFSection( 641 ".debug_aranges", 642 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 643 COFF::IMAGE_SCN_MEM_READ, 644 SectionKind::getMetadata()); 645 DwarfRangesSection = Ctx->getCOFFSection( 646 ".debug_ranges", 647 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 648 COFF::IMAGE_SCN_MEM_READ, 649 SectionKind::getMetadata(), "debug_range"); 650 DwarfInfoDWOSection = Ctx->getCOFFSection( 651 ".debug_info.dwo", 652 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 653 COFF::IMAGE_SCN_MEM_READ, 654 SectionKind::getMetadata(), "section_info_dwo"); 655 DwarfTypesDWOSection = Ctx->getCOFFSection( 656 ".debug_types.dwo", 657 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 658 COFF::IMAGE_SCN_MEM_READ, 659 SectionKind::getMetadata(), "section_types_dwo"); 660 DwarfAbbrevDWOSection = Ctx->getCOFFSection( 661 ".debug_abbrev.dwo", 662 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 663 COFF::IMAGE_SCN_MEM_READ, 664 SectionKind::getMetadata(), "section_abbrev_dwo"); 665 DwarfStrDWOSection = Ctx->getCOFFSection( 666 ".debug_str.dwo", 667 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 668 COFF::IMAGE_SCN_MEM_READ, 669 SectionKind::getMetadata(), "skel_string"); 670 DwarfLineDWOSection = Ctx->getCOFFSection( 671 ".debug_line.dwo", 672 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 673 COFF::IMAGE_SCN_MEM_READ, 674 SectionKind::getMetadata()); 675 DwarfLocDWOSection = Ctx->getCOFFSection( 676 ".debug_loc.dwo", 677 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 678 COFF::IMAGE_SCN_MEM_READ, 679 SectionKind::getMetadata(), "skel_loc"); 680 DwarfStrOffDWOSection = Ctx->getCOFFSection( 681 ".debug_str_offsets.dwo", 682 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 683 COFF::IMAGE_SCN_MEM_READ, 684 SectionKind::getMetadata()); 685 DwarfAddrSection = Ctx->getCOFFSection( 686 ".debug_addr", 687 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 688 COFF::IMAGE_SCN_MEM_READ, 689 SectionKind::getMetadata(), "addr_sec"); 690 DwarfAccelNamesSection = Ctx->getCOFFSection( 691 ".apple_names", 692 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 693 COFF::IMAGE_SCN_MEM_READ, 694 SectionKind::getMetadata(), "names_begin"); 695 DwarfAccelNamespaceSection = Ctx->getCOFFSection( 696 ".apple_namespaces", 697 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 698 COFF::IMAGE_SCN_MEM_READ, 699 SectionKind::getMetadata(), "namespac_begin"); 700 DwarfAccelTypesSection = Ctx->getCOFFSection( 701 ".apple_types", 702 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 703 COFF::IMAGE_SCN_MEM_READ, 704 SectionKind::getMetadata(), "types_begin"); 705 DwarfAccelObjCSection = Ctx->getCOFFSection( 706 ".apple_objc", 707 COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 708 COFF::IMAGE_SCN_MEM_READ, 709 SectionKind::getMetadata(), "objc_begin"); 710 711 DrectveSection = Ctx->getCOFFSection( 712 ".drectve", COFF::IMAGE_SCN_LNK_INFO | COFF::IMAGE_SCN_LNK_REMOVE, 713 SectionKind::getMetadata()); 714 715 PDataSection = Ctx->getCOFFSection( 716 ".pdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 717 SectionKind::getDataRel()); 718 719 XDataSection = Ctx->getCOFFSection( 720 ".xdata", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, 721 SectionKind::getDataRel()); 722 723 SXDataSection = Ctx->getCOFFSection(".sxdata", COFF::IMAGE_SCN_LNK_INFO, 724 SectionKind::getMetadata()); 725 726 TLSDataSection = Ctx->getCOFFSection( 727 ".tls$", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ | 728 COFF::IMAGE_SCN_MEM_WRITE, 729 SectionKind::getDataRel()); 730 } 731 732 void MCObjectFileInfo::InitMCObjectFileInfo(StringRef T, Reloc::Model relocm, 733 CodeModel::Model cm, 734 MCContext &ctx) { 735 RelocM = relocm; 736 CMModel = cm; 737 Ctx = &ctx; 738 739 // Common. 740 CommDirectiveSupportsAlignment = true; 741 SupportsWeakOmittedEHFrame = true; 742 SupportsCompactUnwindWithoutEHFrame = false; 743 744 PersonalityEncoding = LSDAEncoding = FDECFIEncoding = TTypeEncoding = 745 dwarf::DW_EH_PE_absptr; 746 747 CompactUnwindDwarfEHFrameOnly = 0; 748 749 EHFrameSection = nullptr; // Created on demand. 750 CompactUnwindSection = nullptr; // Used only by selected targets. 751 DwarfAccelNamesSection = nullptr; // Used only by selected targets. 752 DwarfAccelObjCSection = nullptr; // Used only by selected targets. 753 DwarfAccelNamespaceSection = nullptr; // Used only by selected targets. 754 DwarfAccelTypesSection = nullptr; // Used only by selected targets. 755 756 TT = Triple(T); 757 758 Triple::ArchType Arch = TT.getArch(); 759 // FIXME: Checking for Arch here to filter out bogus triples such as 760 // cellspu-apple-darwin. Perhaps we should fix in Triple? 761 if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 762 Arch == Triple::arm || Arch == Triple::thumb || 763 Arch == Triple::aarch64 || 764 Arch == Triple::ppc || Arch == Triple::ppc64 || 765 Arch == Triple::UnknownArch) && 766 TT.isOSBinFormatMachO()) { 767 Env = IsMachO; 768 initMachOMCObjectFileInfo(TT); 769 } else if ((Arch == Triple::x86 || Arch == Triple::x86_64 || 770 Arch == Triple::arm || Arch == Triple::thumb) && 771 (TT.isOSWindows() && TT.getObjectFormat() == Triple::COFF)) { 772 Env = IsCOFF; 773 initCOFFMCObjectFileInfo(TT); 774 } else { 775 Env = IsELF; 776 initELFMCObjectFileInfo(TT); 777 } 778 } 779 780 MCSection *MCObjectFileInfo::getDwarfTypesSection(uint64_t Hash) const { 781 return Ctx->getELFSection(".debug_types", ELF::SHT_PROGBITS, ELF::SHF_GROUP, 782 0, utostr(Hash)); 783 } 784 785 void MCObjectFileInfo::InitEHFrameSection() { 786 if (Env == IsMachO) 787 EHFrameSection = 788 Ctx->getMachOSection("__TEXT", "__eh_frame", 789 MachO::S_COALESCED | 790 MachO::S_ATTR_NO_TOC | 791 MachO::S_ATTR_STRIP_STATIC_SYMS | 792 MachO::S_ATTR_LIVE_SUPPORT, 793 SectionKind::getReadOnly()); 794 else if (Env == IsELF) 795 EHFrameSection = 796 Ctx->getELFSection(".eh_frame", EHSectionType, EHSectionFlags); 797 else 798 EHFrameSection = 799 Ctx->getCOFFSection(".eh_frame", 800 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | 801 COFF::IMAGE_SCN_MEM_READ | 802 COFF::IMAGE_SCN_MEM_WRITE, 803 SectionKind::getDataRel()); 804 } 805