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