1 //===- DWARFFormValue.cpp -------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "llvm/DebugInfo/DWARF/DWARFFormValue.h" 10 #include "llvm/ADT/ArrayRef.h" 11 #include "llvm/ADT/None.h" 12 #include "llvm/ADT/Optional.h" 13 #include "llvm/ADT/StringRef.h" 14 #include "llvm/BinaryFormat/Dwarf.h" 15 #include "llvm/DebugInfo/DWARF/DWARFContext.h" 16 #include "llvm/DebugInfo/DWARF/DWARFRelocMap.h" 17 #include "llvm/DebugInfo/DWARF/DWARFUnit.h" 18 #include "llvm/Support/ErrorHandling.h" 19 #include "llvm/Support/Format.h" 20 #include "llvm/Support/WithColor.h" 21 #include "llvm/Support/raw_ostream.h" 22 #include <cinttypes> 23 #include <cstdint> 24 #include <limits> 25 26 using namespace llvm; 27 using namespace dwarf; 28 29 static const DWARFFormValue::FormClass DWARF5FormClasses[] = { 30 DWARFFormValue::FC_Unknown, // 0x0 31 DWARFFormValue::FC_Address, // 0x01 DW_FORM_addr 32 DWARFFormValue::FC_Unknown, // 0x02 unused 33 DWARFFormValue::FC_Block, // 0x03 DW_FORM_block2 34 DWARFFormValue::FC_Block, // 0x04 DW_FORM_block4 35 DWARFFormValue::FC_Constant, // 0x05 DW_FORM_data2 36 // --- These can be FC_SectionOffset in DWARF3 and below: 37 DWARFFormValue::FC_Constant, // 0x06 DW_FORM_data4 38 DWARFFormValue::FC_Constant, // 0x07 DW_FORM_data8 39 // --- 40 DWARFFormValue::FC_String, // 0x08 DW_FORM_string 41 DWARFFormValue::FC_Block, // 0x09 DW_FORM_block 42 DWARFFormValue::FC_Block, // 0x0a DW_FORM_block1 43 DWARFFormValue::FC_Constant, // 0x0b DW_FORM_data1 44 DWARFFormValue::FC_Flag, // 0x0c DW_FORM_flag 45 DWARFFormValue::FC_Constant, // 0x0d DW_FORM_sdata 46 DWARFFormValue::FC_String, // 0x0e DW_FORM_strp 47 DWARFFormValue::FC_Constant, // 0x0f DW_FORM_udata 48 DWARFFormValue::FC_Reference, // 0x10 DW_FORM_ref_addr 49 DWARFFormValue::FC_Reference, // 0x11 DW_FORM_ref1 50 DWARFFormValue::FC_Reference, // 0x12 DW_FORM_ref2 51 DWARFFormValue::FC_Reference, // 0x13 DW_FORM_ref4 52 DWARFFormValue::FC_Reference, // 0x14 DW_FORM_ref8 53 DWARFFormValue::FC_Reference, // 0x15 DW_FORM_ref_udata 54 DWARFFormValue::FC_Indirect, // 0x16 DW_FORM_indirect 55 DWARFFormValue::FC_SectionOffset, // 0x17 DW_FORM_sec_offset 56 DWARFFormValue::FC_Exprloc, // 0x18 DW_FORM_exprloc 57 DWARFFormValue::FC_Flag, // 0x19 DW_FORM_flag_present 58 DWARFFormValue::FC_String, // 0x1a DW_FORM_strx 59 DWARFFormValue::FC_Address, // 0x1b DW_FORM_addrx 60 DWARFFormValue::FC_Reference, // 0x1c DW_FORM_ref_sup4 61 DWARFFormValue::FC_String, // 0x1d DW_FORM_strp_sup 62 DWARFFormValue::FC_Constant, // 0x1e DW_FORM_data16 63 DWARFFormValue::FC_String, // 0x1f DW_FORM_line_strp 64 DWARFFormValue::FC_Reference, // 0x20 DW_FORM_ref_sig8 65 DWARFFormValue::FC_Constant, // 0x21 DW_FORM_implicit_const 66 DWARFFormValue::FC_SectionOffset, // 0x22 DW_FORM_loclistx 67 DWARFFormValue::FC_SectionOffset, // 0x23 DW_FORM_rnglistx 68 DWARFFormValue::FC_Reference, // 0x24 DW_FORM_ref_sup8 69 DWARFFormValue::FC_String, // 0x25 DW_FORM_strx1 70 DWARFFormValue::FC_String, // 0x26 DW_FORM_strx2 71 DWARFFormValue::FC_String, // 0x27 DW_FORM_strx3 72 DWARFFormValue::FC_String, // 0x28 DW_FORM_strx4 73 DWARFFormValue::FC_Address, // 0x29 DW_FORM_addrx1 74 DWARFFormValue::FC_Address, // 0x2a DW_FORM_addrx2 75 DWARFFormValue::FC_Address, // 0x2b DW_FORM_addrx3 76 DWARFFormValue::FC_Address, // 0x2c DW_FORM_addrx4 77 78 }; 79 80 DWARFFormValue DWARFFormValue::createFromSValue(dwarf::Form F, int64_t V) { 81 return DWARFFormValue(F, ValueType(V)); 82 } 83 84 DWARFFormValue DWARFFormValue::createFromUValue(dwarf::Form F, uint64_t V) { 85 return DWARFFormValue(F, ValueType(V)); 86 } 87 88 DWARFFormValue DWARFFormValue::createFromPValue(dwarf::Form F, const char *V) { 89 return DWARFFormValue(F, ValueType(V)); 90 } 91 92 DWARFFormValue DWARFFormValue::createFromBlockValue(dwarf::Form F, 93 ArrayRef<uint8_t> D) { 94 ValueType V; 95 V.uval = D.size(); 96 V.data = D.data(); 97 return DWARFFormValue(F, V); 98 } 99 100 DWARFFormValue DWARFFormValue::createFromUnit(dwarf::Form F, const DWARFUnit *U, 101 uint64_t *OffsetPtr) { 102 DWARFFormValue FormValue(F); 103 FormValue.extractValue(U->getDebugInfoExtractor(), OffsetPtr, 104 U->getFormParams(), U); 105 return FormValue; 106 } 107 108 bool DWARFFormValue::skipValue(dwarf::Form Form, DataExtractor DebugInfoData, 109 uint64_t *OffsetPtr, 110 const dwarf::FormParams Params) { 111 bool Indirect = false; 112 do { 113 switch (Form) { 114 // Blocks of inlined data that have a length field and the data bytes 115 // inlined in the .debug_info. 116 case DW_FORM_exprloc: 117 case DW_FORM_block: { 118 uint64_t size = DebugInfoData.getULEB128(OffsetPtr); 119 *OffsetPtr += size; 120 return true; 121 } 122 case DW_FORM_block1: { 123 uint8_t size = DebugInfoData.getU8(OffsetPtr); 124 *OffsetPtr += size; 125 return true; 126 } 127 case DW_FORM_block2: { 128 uint16_t size = DebugInfoData.getU16(OffsetPtr); 129 *OffsetPtr += size; 130 return true; 131 } 132 case DW_FORM_block4: { 133 uint32_t size = DebugInfoData.getU32(OffsetPtr); 134 *OffsetPtr += size; 135 return true; 136 } 137 138 // Inlined NULL terminated C-strings. 139 case DW_FORM_string: 140 DebugInfoData.getCStr(OffsetPtr); 141 return true; 142 143 case DW_FORM_addr: 144 case DW_FORM_ref_addr: 145 case DW_FORM_flag_present: 146 case DW_FORM_data1: 147 case DW_FORM_data2: 148 case DW_FORM_data4: 149 case DW_FORM_data8: 150 case DW_FORM_data16: 151 case DW_FORM_flag: 152 case DW_FORM_ref1: 153 case DW_FORM_ref2: 154 case DW_FORM_ref4: 155 case DW_FORM_ref8: 156 case DW_FORM_ref_sig8: 157 case DW_FORM_ref_sup4: 158 case DW_FORM_ref_sup8: 159 case DW_FORM_strx1: 160 case DW_FORM_strx2: 161 case DW_FORM_strx4: 162 case DW_FORM_addrx1: 163 case DW_FORM_addrx2: 164 case DW_FORM_addrx4: 165 case DW_FORM_sec_offset: 166 case DW_FORM_strp: 167 case DW_FORM_strp_sup: 168 case DW_FORM_line_strp: 169 case DW_FORM_GNU_ref_alt: 170 case DW_FORM_GNU_strp_alt: 171 if (Optional<uint8_t> FixedSize = 172 dwarf::getFixedFormByteSize(Form, Params)) { 173 *OffsetPtr += *FixedSize; 174 return true; 175 } 176 return false; 177 178 // signed or unsigned LEB 128 values. 179 case DW_FORM_sdata: 180 DebugInfoData.getSLEB128(OffsetPtr); 181 return true; 182 183 case DW_FORM_udata: 184 case DW_FORM_ref_udata: 185 case DW_FORM_strx: 186 case DW_FORM_addrx: 187 case DW_FORM_loclistx: 188 case DW_FORM_rnglistx: 189 case DW_FORM_GNU_addr_index: 190 case DW_FORM_GNU_str_index: 191 DebugInfoData.getULEB128(OffsetPtr); 192 return true; 193 194 case DW_FORM_indirect: 195 Indirect = true; 196 Form = static_cast<dwarf::Form>(DebugInfoData.getULEB128(OffsetPtr)); 197 break; 198 199 default: 200 return false; 201 } 202 } while (Indirect); 203 return true; 204 } 205 206 bool DWARFFormValue::isFormClass(DWARFFormValue::FormClass FC) const { 207 // First, check DWARF5 form classes. 208 if (Form < makeArrayRef(DWARF5FormClasses).size() && 209 DWARF5FormClasses[Form] == FC) 210 return true; 211 // Check more forms from extensions and proposals. 212 switch (Form) { 213 case DW_FORM_GNU_ref_alt: 214 return (FC == FC_Reference); 215 case DW_FORM_GNU_addr_index: 216 return (FC == FC_Address); 217 case DW_FORM_GNU_str_index: 218 case DW_FORM_GNU_strp_alt: 219 return (FC == FC_String); 220 default: 221 break; 222 } 223 224 if (FC == FC_SectionOffset) { 225 if (Form == DW_FORM_strp || Form == DW_FORM_line_strp) 226 return true; 227 // In DWARF3 DW_FORM_data4 and DW_FORM_data8 served also as a section 228 // offset. If we don't have a DWARFUnit, default to the old behavior. 229 if (Form == DW_FORM_data4 || Form == DW_FORM_data8) 230 return !U || U->getVersion() <= 3; 231 } 232 233 return false; 234 } 235 236 bool DWARFFormValue::extractValue(const DWARFDataExtractor &Data, 237 uint64_t *OffsetPtr, dwarf::FormParams FP, 238 const DWARFContext *Ctx, 239 const DWARFUnit *CU) { 240 if (!Ctx && CU) 241 Ctx = &CU->getContext(); 242 C = Ctx; 243 U = CU; 244 Format = FP.Format; 245 bool Indirect = false; 246 bool IsBlock = false; 247 Value.data = nullptr; 248 // Read the value for the form into value and follow and DW_FORM_indirect 249 // instances we run into 250 Error Err = Error::success(); 251 do { 252 Indirect = false; 253 switch (Form) { 254 case DW_FORM_addr: 255 case DW_FORM_ref_addr: { 256 uint16_t Size = 257 (Form == DW_FORM_addr) ? FP.AddrSize : FP.getRefAddrByteSize(); 258 Value.uval = 259 Data.getRelocatedValue(Size, OffsetPtr, &Value.SectionIndex, &Err); 260 break; 261 } 262 case DW_FORM_exprloc: 263 case DW_FORM_block: 264 Value.uval = Data.getULEB128(OffsetPtr, &Err); 265 IsBlock = true; 266 break; 267 case DW_FORM_block1: 268 Value.uval = Data.getU8(OffsetPtr, &Err); 269 IsBlock = true; 270 break; 271 case DW_FORM_block2: 272 Value.uval = Data.getU16(OffsetPtr, &Err); 273 IsBlock = true; 274 break; 275 case DW_FORM_block4: 276 Value.uval = Data.getU32(OffsetPtr, &Err); 277 IsBlock = true; 278 break; 279 case DW_FORM_data1: 280 case DW_FORM_ref1: 281 case DW_FORM_flag: 282 case DW_FORM_strx1: 283 case DW_FORM_addrx1: 284 Value.uval = Data.getU8(OffsetPtr, &Err); 285 break; 286 case DW_FORM_data2: 287 case DW_FORM_ref2: 288 case DW_FORM_strx2: 289 case DW_FORM_addrx2: 290 Value.uval = Data.getU16(OffsetPtr, &Err); 291 break; 292 case DW_FORM_strx3: 293 Value.uval = Data.getU24(OffsetPtr, &Err); 294 break; 295 case DW_FORM_data4: 296 case DW_FORM_ref4: 297 case DW_FORM_ref_sup4: 298 case DW_FORM_strx4: 299 case DW_FORM_addrx4: 300 Value.uval = Data.getRelocatedValue(4, OffsetPtr, nullptr, &Err); 301 break; 302 case DW_FORM_data8: 303 case DW_FORM_ref8: 304 case DW_FORM_ref_sup8: 305 Value.uval = Data.getRelocatedValue(8, OffsetPtr, nullptr, &Err); 306 break; 307 case DW_FORM_data16: 308 // Treat this like a 16-byte block. 309 Value.uval = 16; 310 IsBlock = true; 311 break; 312 case DW_FORM_sdata: 313 Value.sval = Data.getSLEB128(OffsetPtr, &Err); 314 break; 315 case DW_FORM_udata: 316 case DW_FORM_ref_udata: 317 case DW_FORM_rnglistx: 318 case DW_FORM_loclistx: 319 case DW_FORM_GNU_addr_index: 320 case DW_FORM_GNU_str_index: 321 case DW_FORM_addrx: 322 case DW_FORM_strx: 323 Value.uval = Data.getULEB128(OffsetPtr, &Err); 324 break; 325 case DW_FORM_string: 326 Value.cstr = Data.getCStr(OffsetPtr, &Err); 327 break; 328 case DW_FORM_indirect: 329 Form = static_cast<dwarf::Form>(Data.getULEB128(OffsetPtr, &Err)); 330 Indirect = true; 331 break; 332 case DW_FORM_strp: 333 case DW_FORM_sec_offset: 334 case DW_FORM_GNU_ref_alt: 335 case DW_FORM_GNU_strp_alt: 336 case DW_FORM_line_strp: 337 case DW_FORM_strp_sup: { 338 Value.uval = Data.getRelocatedValue(FP.getDwarfOffsetByteSize(), 339 OffsetPtr, nullptr, &Err); 340 break; 341 } 342 case DW_FORM_flag_present: 343 Value.uval = 1; 344 break; 345 case DW_FORM_ref_sig8: 346 Value.uval = Data.getU64(OffsetPtr, &Err); 347 break; 348 default: 349 // DWARFFormValue::skipValue() will have caught this and caused all 350 // DWARF DIEs to fail to be parsed, so this code is not be reachable. 351 llvm_unreachable("unsupported form"); 352 } 353 } while (Indirect && !Err); 354 355 if (IsBlock) 356 Value.data = Data.getBytes(OffsetPtr, Value.uval, &Err).bytes_begin(); 357 358 return !errorToBool(std::move(Err)); 359 } 360 361 void DWARFFormValue::dumpAddress(raw_ostream &OS, uint8_t AddressSize, 362 uint64_t Address) { 363 uint8_t HexDigits = AddressSize * 2; 364 OS << format("0x%*.*" PRIx64, HexDigits, HexDigits, Address); 365 } 366 367 void DWARFFormValue::dumpSectionedAddress(raw_ostream &OS, 368 DIDumpOptions DumpOpts, 369 object::SectionedAddress SA) const { 370 dumpAddress(OS, U->getAddressByteSize(), SA.Address); 371 dumpAddressSection(U->getContext().getDWARFObj(), OS, DumpOpts, 372 SA.SectionIndex); 373 } 374 375 void DWARFFormValue::dumpAddressSection(const DWARFObject &Obj, raw_ostream &OS, 376 DIDumpOptions DumpOpts, 377 uint64_t SectionIndex) { 378 if (!DumpOpts.Verbose || SectionIndex == -1ULL) 379 return; 380 ArrayRef<SectionName> SectionNames = Obj.getSectionNames(); 381 const auto &SecRef = SectionNames[SectionIndex]; 382 383 OS << " \"" << SecRef.Name << '\"'; 384 385 // Print section index if name is not unique. 386 if (!SecRef.IsNameUnique) 387 OS << format(" [%" PRIu64 "]", SectionIndex); 388 } 389 390 void DWARFFormValue::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const { 391 uint64_t UValue = Value.uval; 392 bool CURelativeOffset = false; 393 raw_ostream &AddrOS = DumpOpts.ShowAddresses 394 ? WithColor(OS, HighlightColor::Address).get() 395 : nulls(); 396 int OffsetDumpWidth = 2 * dwarf::getDwarfOffsetByteSize(Format); 397 switch (Form) { 398 case DW_FORM_addr: 399 dumpSectionedAddress(AddrOS, DumpOpts, {Value.uval, Value.SectionIndex}); 400 break; 401 case DW_FORM_addrx: 402 case DW_FORM_addrx1: 403 case DW_FORM_addrx2: 404 case DW_FORM_addrx3: 405 case DW_FORM_addrx4: 406 case DW_FORM_GNU_addr_index: { 407 if (U == nullptr) { 408 OS << "<invalid dwarf unit>"; 409 break; 410 } 411 Optional<object::SectionedAddress> A = U->getAddrOffsetSectionItem(UValue); 412 if (!A || DumpOpts.Verbose) 413 AddrOS << format("indexed (%8.8x) address = ", (uint32_t)UValue); 414 if (A) 415 dumpSectionedAddress(AddrOS, DumpOpts, *A); 416 else 417 OS << "<unresolved>"; 418 break; 419 } 420 case DW_FORM_flag_present: 421 OS << "true"; 422 break; 423 case DW_FORM_flag: 424 case DW_FORM_data1: 425 OS << format("0x%02x", (uint8_t)UValue); 426 break; 427 case DW_FORM_data2: 428 OS << format("0x%04x", (uint16_t)UValue); 429 break; 430 case DW_FORM_data4: 431 OS << format("0x%08x", (uint32_t)UValue); 432 break; 433 case DW_FORM_ref_sig8: 434 AddrOS << format("0x%016" PRIx64, UValue); 435 break; 436 case DW_FORM_data8: 437 OS << format("0x%016" PRIx64, UValue); 438 break; 439 case DW_FORM_data16: 440 OS << format_bytes(ArrayRef<uint8_t>(Value.data, 16), None, 16, 16); 441 break; 442 case DW_FORM_string: 443 OS << '"'; 444 OS.write_escaped(Value.cstr); 445 OS << '"'; 446 break; 447 case DW_FORM_exprloc: 448 case DW_FORM_block: 449 case DW_FORM_block1: 450 case DW_FORM_block2: 451 case DW_FORM_block4: 452 if (UValue > 0) { 453 switch (Form) { 454 case DW_FORM_exprloc: 455 case DW_FORM_block: 456 AddrOS << format("<0x%" PRIx64 "> ", UValue); 457 break; 458 case DW_FORM_block1: 459 AddrOS << format("<0x%2.2x> ", (uint8_t)UValue); 460 break; 461 case DW_FORM_block2: 462 AddrOS << format("<0x%4.4x> ", (uint16_t)UValue); 463 break; 464 case DW_FORM_block4: 465 AddrOS << format("<0x%8.8x> ", (uint32_t)UValue); 466 break; 467 default: 468 break; 469 } 470 471 const uint8_t *DataPtr = Value.data; 472 if (DataPtr) { 473 // UValue contains size of block 474 const uint8_t *EndDataPtr = DataPtr + UValue; 475 while (DataPtr < EndDataPtr) { 476 AddrOS << format("%2.2x ", *DataPtr); 477 ++DataPtr; 478 } 479 } else 480 OS << "NULL"; 481 } 482 break; 483 484 case DW_FORM_sdata: 485 OS << Value.sval; 486 break; 487 case DW_FORM_udata: 488 OS << Value.uval; 489 break; 490 case DW_FORM_strp: 491 if (DumpOpts.Verbose) 492 OS << format(" .debug_str[0x%0*" PRIx64 "] = ", OffsetDumpWidth, UValue); 493 dumpString(OS); 494 break; 495 case DW_FORM_line_strp: 496 if (DumpOpts.Verbose) 497 OS << format(" .debug_line_str[0x%0*" PRIx64 "] = ", OffsetDumpWidth, 498 UValue); 499 dumpString(OS); 500 break; 501 case DW_FORM_strx: 502 case DW_FORM_strx1: 503 case DW_FORM_strx2: 504 case DW_FORM_strx3: 505 case DW_FORM_strx4: 506 case DW_FORM_GNU_str_index: 507 if (DumpOpts.Verbose) 508 OS << format("indexed (%8.8x) string = ", (uint32_t)UValue); 509 dumpString(OS); 510 break; 511 case DW_FORM_GNU_strp_alt: 512 if (DumpOpts.Verbose) 513 OS << format("alt indirect string, offset: 0x%" PRIx64 "", UValue); 514 dumpString(OS); 515 break; 516 case DW_FORM_ref_addr: 517 AddrOS << format("0x%016" PRIx64, UValue); 518 break; 519 case DW_FORM_ref1: 520 CURelativeOffset = true; 521 if (DumpOpts.Verbose) 522 AddrOS << format("cu + 0x%2.2x", (uint8_t)UValue); 523 break; 524 case DW_FORM_ref2: 525 CURelativeOffset = true; 526 if (DumpOpts.Verbose) 527 AddrOS << format("cu + 0x%4.4x", (uint16_t)UValue); 528 break; 529 case DW_FORM_ref4: 530 CURelativeOffset = true; 531 if (DumpOpts.Verbose) 532 AddrOS << format("cu + 0x%4.4x", (uint32_t)UValue); 533 break; 534 case DW_FORM_ref8: 535 CURelativeOffset = true; 536 if (DumpOpts.Verbose) 537 AddrOS << format("cu + 0x%8.8" PRIx64, UValue); 538 break; 539 case DW_FORM_ref_udata: 540 CURelativeOffset = true; 541 if (DumpOpts.Verbose) 542 AddrOS << format("cu + 0x%" PRIx64, UValue); 543 break; 544 case DW_FORM_GNU_ref_alt: 545 AddrOS << format("<alt 0x%" PRIx64 ">", UValue); 546 break; 547 548 // All DW_FORM_indirect attributes should be resolved prior to calling 549 // this function 550 case DW_FORM_indirect: 551 OS << "DW_FORM_indirect"; 552 break; 553 554 case DW_FORM_rnglistx: 555 OS << format("indexed (0x%x) rangelist = ", (uint32_t)UValue); 556 break; 557 558 case DW_FORM_loclistx: 559 OS << format("indexed (0x%x) loclist = ", (uint32_t)UValue); 560 break; 561 562 case DW_FORM_sec_offset: 563 AddrOS << format("0x%0*" PRIx64, OffsetDumpWidth, UValue); 564 break; 565 566 default: 567 OS << format("DW_FORM(0x%4.4x)", Form); 568 break; 569 } 570 571 if (CURelativeOffset) { 572 if (DumpOpts.Verbose) 573 OS << " => {"; 574 if (DumpOpts.ShowAddresses) 575 WithColor(OS, HighlightColor::Address).get() 576 << format("0x%8.8" PRIx64, UValue + (U ? U->getOffset() : 0)); 577 if (DumpOpts.Verbose) 578 OS << "}"; 579 } 580 } 581 582 void DWARFFormValue::dumpString(raw_ostream &OS) const { 583 Optional<const char *> DbgStr = getAsCString(); 584 if (DbgStr.hasValue()) { 585 auto COS = WithColor(OS, HighlightColor::String); 586 COS.get() << '"'; 587 COS.get().write_escaped(DbgStr.getValue()); 588 COS.get() << '"'; 589 } 590 } 591 592 Optional<const char *> DWARFFormValue::getAsCString() const { 593 if (!isFormClass(FC_String)) 594 return None; 595 if (Form == DW_FORM_string) 596 return Value.cstr; 597 // FIXME: Add support for DW_FORM_GNU_strp_alt 598 if (Form == DW_FORM_GNU_strp_alt || C == nullptr) 599 return None; 600 uint64_t Offset = Value.uval; 601 if (Form == DW_FORM_line_strp) { 602 // .debug_line_str is tracked in the Context. 603 if (const char *Str = C->getLineStringExtractor().getCStr(&Offset)) 604 return Str; 605 return None; 606 } 607 if (Form == DW_FORM_GNU_str_index || Form == DW_FORM_strx || 608 Form == DW_FORM_strx1 || Form == DW_FORM_strx2 || Form == DW_FORM_strx3 || 609 Form == DW_FORM_strx4) { 610 if (!U) 611 return None; 612 Optional<uint64_t> StrOffset = U->getStringOffsetSectionItem(Offset); 613 if (!StrOffset) 614 return None; 615 Offset = *StrOffset; 616 } 617 // Prefer the Unit's string extractor, because for .dwo it will point to 618 // .debug_str.dwo, while the Context's extractor always uses .debug_str. 619 if (U) { 620 if (const char *Str = U->getStringExtractor().getCStr(&Offset)) 621 return Str; 622 return None; 623 } 624 if (const char *Str = C->getStringExtractor().getCStr(&Offset)) 625 return Str; 626 return None; 627 } 628 629 Optional<uint64_t> DWARFFormValue::getAsAddress() const { 630 if (auto SA = getAsSectionedAddress()) 631 return SA->Address; 632 return None; 633 } 634 635 Optional<object::SectionedAddress> 636 DWARFFormValue::getAsSectionedAddress() const { 637 if (!isFormClass(FC_Address)) 638 return None; 639 if (Form == DW_FORM_GNU_addr_index || Form == DW_FORM_addrx) { 640 uint32_t Index = Value.uval; 641 if (!U) 642 return None; 643 Optional<object::SectionedAddress> SA = U->getAddrOffsetSectionItem(Index); 644 if (!SA) 645 return None; 646 return SA; 647 } 648 return {{Value.uval, Value.SectionIndex}}; 649 } 650 651 Optional<uint64_t> DWARFFormValue::getAsReference() const { 652 if (auto R = getAsRelativeReference()) 653 return R->Unit ? R->Unit->getOffset() + R->Offset : R->Offset; 654 return None; 655 } 656 657 Optional<DWARFFormValue::UnitOffset> DWARFFormValue::getAsRelativeReference() const { 658 if (!isFormClass(FC_Reference)) 659 return None; 660 switch (Form) { 661 case DW_FORM_ref1: 662 case DW_FORM_ref2: 663 case DW_FORM_ref4: 664 case DW_FORM_ref8: 665 case DW_FORM_ref_udata: 666 if (!U) 667 return None; 668 return UnitOffset{const_cast<DWARFUnit*>(U), Value.uval}; 669 case DW_FORM_ref_addr: 670 case DW_FORM_ref_sig8: 671 case DW_FORM_GNU_ref_alt: 672 return UnitOffset{nullptr, Value.uval}; 673 default: 674 return None; 675 } 676 } 677 678 Optional<uint64_t> DWARFFormValue::getAsSectionOffset() const { 679 if (!isFormClass(FC_SectionOffset)) 680 return None; 681 return Value.uval; 682 } 683 684 Optional<uint64_t> DWARFFormValue::getAsUnsignedConstant() const { 685 if ((!isFormClass(FC_Constant) && !isFormClass(FC_Flag)) || 686 Form == DW_FORM_sdata) 687 return None; 688 return Value.uval; 689 } 690 691 Optional<int64_t> DWARFFormValue::getAsSignedConstant() const { 692 if ((!isFormClass(FC_Constant) && !isFormClass(FC_Flag)) || 693 (Form == DW_FORM_udata && 694 uint64_t(std::numeric_limits<int64_t>::max()) < Value.uval)) 695 return None; 696 switch (Form) { 697 case DW_FORM_data4: 698 return int32_t(Value.uval); 699 case DW_FORM_data2: 700 return int16_t(Value.uval); 701 case DW_FORM_data1: 702 return int8_t(Value.uval); 703 case DW_FORM_sdata: 704 case DW_FORM_data8: 705 default: 706 return Value.sval; 707 } 708 } 709 710 Optional<ArrayRef<uint8_t>> DWARFFormValue::getAsBlock() const { 711 if (!isFormClass(FC_Block) && !isFormClass(FC_Exprloc) && 712 Form != DW_FORM_data16) 713 return None; 714 return makeArrayRef(Value.data, Value.uval); 715 } 716 717 Optional<uint64_t> DWARFFormValue::getAsCStringOffset() const { 718 if (!isFormClass(FC_String) && Form == DW_FORM_string) 719 return None; 720 return Value.uval; 721 } 722 723 Optional<uint64_t> DWARFFormValue::getAsReferenceUVal() const { 724 if (!isFormClass(FC_Reference)) 725 return None; 726 return Value.uval; 727 } 728