1 //===- DWARFFormValue.cpp -------------------------------------------------===// 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/DebugInfo/DWARF/DWARFFormValue.h" 11 #include "llvm/ADT/ArrayRef.h" 12 #include "llvm/ADT/None.h" 13 #include "llvm/ADT/Optional.h" 14 #include "llvm/ADT/StringRef.h" 15 #include "llvm/BinaryFormat/Dwarf.h" 16 #include "llvm/DebugInfo/DWARF/DWARFContext.h" 17 #include "llvm/DebugInfo/DWARF/DWARFRelocMap.h" 18 #include "llvm/DebugInfo/DWARF/DWARFUnit.h" 19 #include "llvm/Support/ErrorHandling.h" 20 #include "llvm/Support/Format.h" 21 #include "llvm/Support/WithColor.h" 22 #include "llvm/Support/raw_ostream.h" 23 #include <cinttypes> 24 #include <cstdint> 25 #include <limits> 26 27 using namespace llvm; 28 using namespace dwarf; 29 30 static const DWARFFormValue::FormClass DWARF5FormClasses[] = { 31 DWARFFormValue::FC_Unknown, // 0x0 32 DWARFFormValue::FC_Address, // 0x01 DW_FORM_addr 33 DWARFFormValue::FC_Unknown, // 0x02 unused 34 DWARFFormValue::FC_Block, // 0x03 DW_FORM_block2 35 DWARFFormValue::FC_Block, // 0x04 DW_FORM_block4 36 DWARFFormValue::FC_Constant, // 0x05 DW_FORM_data2 37 // --- These can be FC_SectionOffset in DWARF3 and below: 38 DWARFFormValue::FC_Constant, // 0x06 DW_FORM_data4 39 DWARFFormValue::FC_Constant, // 0x07 DW_FORM_data8 40 // --- 41 DWARFFormValue::FC_String, // 0x08 DW_FORM_string 42 DWARFFormValue::FC_Block, // 0x09 DW_FORM_block 43 DWARFFormValue::FC_Block, // 0x0a DW_FORM_block1 44 DWARFFormValue::FC_Constant, // 0x0b DW_FORM_data1 45 DWARFFormValue::FC_Flag, // 0x0c DW_FORM_flag 46 DWARFFormValue::FC_Constant, // 0x0d DW_FORM_sdata 47 DWARFFormValue::FC_String, // 0x0e DW_FORM_strp 48 DWARFFormValue::FC_Constant, // 0x0f DW_FORM_udata 49 DWARFFormValue::FC_Reference, // 0x10 DW_FORM_ref_addr 50 DWARFFormValue::FC_Reference, // 0x11 DW_FORM_ref1 51 DWARFFormValue::FC_Reference, // 0x12 DW_FORM_ref2 52 DWARFFormValue::FC_Reference, // 0x13 DW_FORM_ref4 53 DWARFFormValue::FC_Reference, // 0x14 DW_FORM_ref8 54 DWARFFormValue::FC_Reference, // 0x15 DW_FORM_ref_udata 55 DWARFFormValue::FC_Indirect, // 0x16 DW_FORM_indirect 56 DWARFFormValue::FC_SectionOffset, // 0x17 DW_FORM_sec_offset 57 DWARFFormValue::FC_Exprloc, // 0x18 DW_FORM_exprloc 58 DWARFFormValue::FC_Flag, // 0x19 DW_FORM_flag_present 59 DWARFFormValue::FC_String, // 0x1a DW_FORM_strx 60 DWARFFormValue::FC_Address, // 0x1b DW_FORM_addrx 61 DWARFFormValue::FC_Reference, // 0x1c DW_FORM_ref_sup4 62 DWARFFormValue::FC_String, // 0x1d DW_FORM_strp_sup 63 DWARFFormValue::FC_Constant, // 0x1e DW_FORM_data16 64 DWARFFormValue::FC_String, // 0x1f DW_FORM_line_strp 65 DWARFFormValue::FC_Reference, // 0x20 DW_FORM_ref_sig8 66 DWARFFormValue::FC_Constant, // 0x21 DW_FORM_implicit_const 67 DWARFFormValue::FC_SectionOffset, // 0x22 DW_FORM_loclistx 68 DWARFFormValue::FC_SectionOffset, // 0x23 DW_FORM_rnglistx 69 DWARFFormValue::FC_Reference, // 0x24 DW_FORM_ref_sup8 70 DWARFFormValue::FC_String, // 0x25 DW_FORM_strx1 71 DWARFFormValue::FC_String, // 0x26 DW_FORM_strx2 72 DWARFFormValue::FC_String, // 0x27 DW_FORM_strx3 73 DWARFFormValue::FC_String, // 0x28 DW_FORM_strx4 74 DWARFFormValue::FC_Address, // 0x29 DW_FORM_addrx1 75 DWARFFormValue::FC_Address, // 0x2a DW_FORM_addrx2 76 DWARFFormValue::FC_Address, // 0x2b DW_FORM_addrx3 77 DWARFFormValue::FC_Address, // 0x2c DW_FORM_addrx4 78 79 }; 80 81 bool DWARFFormValue::skipValue(dwarf::Form Form, DataExtractor DebugInfoData, 82 uint32_t *OffsetPtr, 83 const dwarf::FormParams Params) { 84 bool Indirect = false; 85 do { 86 switch (Form) { 87 // Blocks of inlined data that have a length field and the data bytes 88 // inlined in the .debug_info. 89 case DW_FORM_exprloc: 90 case DW_FORM_block: { 91 uint64_t size = DebugInfoData.getULEB128(OffsetPtr); 92 *OffsetPtr += size; 93 return true; 94 } 95 case DW_FORM_block1: { 96 uint8_t size = DebugInfoData.getU8(OffsetPtr); 97 *OffsetPtr += size; 98 return true; 99 } 100 case DW_FORM_block2: { 101 uint16_t size = DebugInfoData.getU16(OffsetPtr); 102 *OffsetPtr += size; 103 return true; 104 } 105 case DW_FORM_block4: { 106 uint32_t size = DebugInfoData.getU32(OffsetPtr); 107 *OffsetPtr += size; 108 return true; 109 } 110 111 // Inlined NULL terminated C-strings. 112 case DW_FORM_string: 113 DebugInfoData.getCStr(OffsetPtr); 114 return true; 115 116 case DW_FORM_addr: 117 case DW_FORM_ref_addr: 118 case DW_FORM_flag_present: 119 case DW_FORM_data1: 120 case DW_FORM_data2: 121 case DW_FORM_data4: 122 case DW_FORM_data8: 123 case DW_FORM_data16: 124 case DW_FORM_flag: 125 case DW_FORM_ref1: 126 case DW_FORM_ref2: 127 case DW_FORM_ref4: 128 case DW_FORM_ref8: 129 case DW_FORM_ref_sig8: 130 case DW_FORM_ref_sup4: 131 case DW_FORM_ref_sup8: 132 case DW_FORM_strx1: 133 case DW_FORM_strx2: 134 case DW_FORM_strx4: 135 case DW_FORM_addrx1: 136 case DW_FORM_addrx2: 137 case DW_FORM_addrx4: 138 case DW_FORM_sec_offset: 139 case DW_FORM_strp: 140 case DW_FORM_strp_sup: 141 case DW_FORM_line_strp: 142 case DW_FORM_GNU_ref_alt: 143 case DW_FORM_GNU_strp_alt: 144 if (Optional<uint8_t> FixedSize = 145 dwarf::getFixedFormByteSize(Form, Params)) { 146 *OffsetPtr += *FixedSize; 147 return true; 148 } 149 return false; 150 151 // signed or unsigned LEB 128 values. 152 case DW_FORM_sdata: 153 DebugInfoData.getSLEB128(OffsetPtr); 154 return true; 155 156 case DW_FORM_udata: 157 case DW_FORM_ref_udata: 158 case DW_FORM_strx: 159 case DW_FORM_addrx: 160 case DW_FORM_loclistx: 161 case DW_FORM_rnglistx: 162 case DW_FORM_GNU_addr_index: 163 case DW_FORM_GNU_str_index: 164 DebugInfoData.getULEB128(OffsetPtr); 165 return true; 166 167 case DW_FORM_indirect: 168 Indirect = true; 169 Form = static_cast<dwarf::Form>(DebugInfoData.getULEB128(OffsetPtr)); 170 break; 171 172 default: 173 return false; 174 } 175 } while (Indirect); 176 return true; 177 } 178 179 bool DWARFFormValue::isFormClass(DWARFFormValue::FormClass FC) const { 180 // First, check DWARF5 form classes. 181 if (Form < makeArrayRef(DWARF5FormClasses).size() && 182 DWARF5FormClasses[Form] == FC) 183 return true; 184 // Check more forms from extensions and proposals. 185 switch (Form) { 186 case DW_FORM_GNU_ref_alt: 187 return (FC == FC_Reference); 188 case DW_FORM_GNU_addr_index: 189 return (FC == FC_Address); 190 case DW_FORM_GNU_str_index: 191 case DW_FORM_GNU_strp_alt: 192 return (FC == FC_String); 193 default: 194 break; 195 } 196 // In DWARF3 DW_FORM_data4 and DW_FORM_data8 served also as a section offset. 197 // Don't check for DWARF version here, as some producers may still do this 198 // by mistake. Also accept DW_FORM_[line_]strp since these are 199 // .debug_[line_]str section offsets. 200 return (Form == DW_FORM_data4 || Form == DW_FORM_data8 || 201 Form == DW_FORM_strp || Form == DW_FORM_line_strp) && 202 FC == FC_SectionOffset; 203 } 204 205 bool DWARFFormValue::extractValue(const DWARFDataExtractor &Data, 206 uint32_t *OffsetPtr, dwarf::FormParams FP, 207 const DWARFContext *Ctx, 208 const DWARFUnit *CU) { 209 if (!Ctx && CU) 210 Ctx = &CU->getContext(); 211 C = Ctx; 212 U = CU; 213 bool Indirect = false; 214 bool IsBlock = false; 215 Value.data = nullptr; 216 // Read the value for the form into value and follow and DW_FORM_indirect 217 // instances we run into 218 do { 219 Indirect = false; 220 switch (Form) { 221 case DW_FORM_addr: 222 case DW_FORM_ref_addr: { 223 uint16_t Size = 224 (Form == DW_FORM_addr) ? FP.AddrSize : FP.getRefAddrByteSize(); 225 Value.uval = Data.getRelocatedValue(Size, OffsetPtr, &Value.SectionIndex); 226 break; 227 } 228 case DW_FORM_exprloc: 229 case DW_FORM_block: 230 Value.uval = Data.getULEB128(OffsetPtr); 231 IsBlock = true; 232 break; 233 case DW_FORM_block1: 234 Value.uval = Data.getU8(OffsetPtr); 235 IsBlock = true; 236 break; 237 case DW_FORM_block2: 238 Value.uval = Data.getU16(OffsetPtr); 239 IsBlock = true; 240 break; 241 case DW_FORM_block4: 242 Value.uval = Data.getU32(OffsetPtr); 243 IsBlock = true; 244 break; 245 case DW_FORM_data1: 246 case DW_FORM_ref1: 247 case DW_FORM_flag: 248 case DW_FORM_strx1: 249 case DW_FORM_addrx1: 250 Value.uval = Data.getU8(OffsetPtr); 251 break; 252 case DW_FORM_data2: 253 case DW_FORM_ref2: 254 case DW_FORM_strx2: 255 case DW_FORM_addrx2: 256 Value.uval = Data.getU16(OffsetPtr); 257 break; 258 case DW_FORM_strx3: 259 Value.uval = Data.getU24(OffsetPtr); 260 break; 261 case DW_FORM_data4: 262 case DW_FORM_ref4: 263 case DW_FORM_ref_sup4: 264 case DW_FORM_strx4: 265 case DW_FORM_addrx4: 266 Value.uval = Data.getRelocatedValue(4, OffsetPtr); 267 break; 268 case DW_FORM_data8: 269 case DW_FORM_ref8: 270 case DW_FORM_ref_sup8: 271 Value.uval = Data.getU64(OffsetPtr); 272 break; 273 case DW_FORM_data16: 274 // Treat this like a 16-byte block. 275 Value.uval = 16; 276 IsBlock = true; 277 break; 278 case DW_FORM_sdata: 279 Value.sval = Data.getSLEB128(OffsetPtr); 280 break; 281 case DW_FORM_udata: 282 case DW_FORM_ref_udata: 283 case DW_FORM_rnglistx: 284 Value.uval = Data.getULEB128(OffsetPtr); 285 break; 286 case DW_FORM_string: 287 Value.cstr = Data.getCStr(OffsetPtr); 288 break; 289 case DW_FORM_indirect: 290 Form = static_cast<dwarf::Form>(Data.getULEB128(OffsetPtr)); 291 Indirect = true; 292 break; 293 case DW_FORM_strp: 294 case DW_FORM_sec_offset: 295 case DW_FORM_GNU_ref_alt: 296 case DW_FORM_GNU_strp_alt: 297 case DW_FORM_line_strp: 298 case DW_FORM_strp_sup: { 299 Value.uval = 300 Data.getRelocatedValue(FP.getDwarfOffsetByteSize(), OffsetPtr); 301 break; 302 } 303 case DW_FORM_flag_present: 304 Value.uval = 1; 305 break; 306 case DW_FORM_ref_sig8: 307 Value.uval = Data.getU64(OffsetPtr); 308 break; 309 case DW_FORM_GNU_addr_index: 310 case DW_FORM_GNU_str_index: 311 case DW_FORM_strx: 312 Value.uval = Data.getULEB128(OffsetPtr); 313 break; 314 default: 315 // DWARFFormValue::skipValue() will have caught this and caused all 316 // DWARF DIEs to fail to be parsed, so this code is not be reachable. 317 llvm_unreachable("unsupported form"); 318 } 319 } while (Indirect); 320 321 if (IsBlock) { 322 StringRef Str = Data.getData().substr(*OffsetPtr, Value.uval); 323 Value.data = nullptr; 324 if (!Str.empty()) { 325 Value.data = reinterpret_cast<const uint8_t *>(Str.data()); 326 *OffsetPtr += Value.uval; 327 } 328 } 329 330 return true; 331 } 332 333 void DWARFFormValue::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const { 334 uint64_t UValue = Value.uval; 335 bool CURelativeOffset = false; 336 raw_ostream &AddrOS = DumpOpts.ShowAddresses 337 ? WithColor(OS, HighlightColor::Address).get() 338 : nulls(); 339 switch (Form) { 340 case DW_FORM_addr: 341 AddrOS << format("0x%016" PRIx64, UValue); 342 break; 343 case DW_FORM_GNU_addr_index: { 344 AddrOS << format(" indexed (%8.8x) address = ", (uint32_t)UValue); 345 uint64_t Address; 346 if (U == nullptr) 347 OS << "<invalid dwarf unit>"; 348 else if (U->getAddrOffsetSectionItem(UValue, Address)) 349 AddrOS << format("0x%016" PRIx64, Address); 350 else 351 OS << "<no .debug_addr section>"; 352 break; 353 } 354 case DW_FORM_flag_present: 355 OS << "true"; 356 break; 357 case DW_FORM_flag: 358 case DW_FORM_data1: 359 OS << format("0x%02x", (uint8_t)UValue); 360 break; 361 case DW_FORM_data2: 362 OS << format("0x%04x", (uint16_t)UValue); 363 break; 364 case DW_FORM_data4: 365 OS << format("0x%08x", (uint32_t)UValue); 366 break; 367 case DW_FORM_ref_sig8: 368 AddrOS << format("0x%016" PRIx64, UValue); 369 break; 370 case DW_FORM_data8: 371 OS << format("0x%016" PRIx64, UValue); 372 break; 373 case DW_FORM_data16: 374 OS << format_bytes(ArrayRef<uint8_t>(Value.data, 16), None, 16, 16); 375 break; 376 case DW_FORM_string: 377 OS << '"'; 378 OS.write_escaped(Value.cstr); 379 OS << '"'; 380 break; 381 case DW_FORM_exprloc: 382 case DW_FORM_block: 383 case DW_FORM_block1: 384 case DW_FORM_block2: 385 case DW_FORM_block4: 386 if (UValue > 0) { 387 switch (Form) { 388 case DW_FORM_exprloc: 389 case DW_FORM_block: 390 OS << format("<0x%" PRIx64 "> ", UValue); 391 break; 392 case DW_FORM_block1: 393 OS << format("<0x%2.2x> ", (uint8_t)UValue); 394 break; 395 case DW_FORM_block2: 396 OS << format("<0x%4.4x> ", (uint16_t)UValue); 397 break; 398 case DW_FORM_block4: 399 OS << format("<0x%8.8x> ", (uint32_t)UValue); 400 break; 401 default: 402 break; 403 } 404 405 const uint8_t *DataPtr = Value.data; 406 if (DataPtr) { 407 // UValue contains size of block 408 const uint8_t *EndDataPtr = DataPtr + UValue; 409 while (DataPtr < EndDataPtr) { 410 OS << format("%2.2x ", *DataPtr); 411 ++DataPtr; 412 } 413 } else 414 OS << "NULL"; 415 } 416 break; 417 418 case DW_FORM_sdata: 419 OS << Value.sval; 420 break; 421 case DW_FORM_udata: 422 OS << Value.uval; 423 break; 424 case DW_FORM_strp: 425 if (DumpOpts.Verbose) 426 OS << format(" .debug_str[0x%8.8x] = ", (uint32_t)UValue); 427 dumpString(OS); 428 break; 429 case DW_FORM_line_strp: 430 if (DumpOpts.Verbose) 431 OS << format(" .debug_line_str[0x%8.8x] = ", (uint32_t)UValue); 432 dumpString(OS); 433 break; 434 case DW_FORM_strx: 435 case DW_FORM_strx1: 436 case DW_FORM_strx2: 437 case DW_FORM_strx3: 438 case DW_FORM_strx4: 439 case DW_FORM_GNU_str_index: 440 if (DumpOpts.Verbose) 441 OS << format(" indexed (%8.8x) string = ", (uint32_t)UValue); 442 dumpString(OS); 443 break; 444 case DW_FORM_GNU_strp_alt: 445 if (DumpOpts.Verbose) 446 OS << format("alt indirect string, offset: 0x%" PRIx64 "", UValue); 447 dumpString(OS); 448 break; 449 case DW_FORM_ref_addr: 450 AddrOS << format("0x%016" PRIx64, UValue); 451 break; 452 case DW_FORM_ref1: 453 CURelativeOffset = true; 454 if (DumpOpts.Verbose) 455 AddrOS << format("cu + 0x%2.2x", (uint8_t)UValue); 456 break; 457 case DW_FORM_ref2: 458 CURelativeOffset = true; 459 if (DumpOpts.Verbose) 460 AddrOS << format("cu + 0x%4.4x", (uint16_t)UValue); 461 break; 462 case DW_FORM_ref4: 463 CURelativeOffset = true; 464 if (DumpOpts.Verbose) 465 AddrOS << format("cu + 0x%4.4x", (uint32_t)UValue); 466 break; 467 case DW_FORM_ref8: 468 CURelativeOffset = true; 469 if (DumpOpts.Verbose) 470 AddrOS << format("cu + 0x%8.8" PRIx64, UValue); 471 break; 472 case DW_FORM_ref_udata: 473 CURelativeOffset = true; 474 if (DumpOpts.Verbose) 475 AddrOS << format("cu + 0x%" PRIx64, UValue); 476 break; 477 case DW_FORM_GNU_ref_alt: 478 AddrOS << format("<alt 0x%" PRIx64 ">", UValue); 479 break; 480 481 // All DW_FORM_indirect attributes should be resolved prior to calling 482 // this function 483 case DW_FORM_indirect: 484 OS << "DW_FORM_indirect"; 485 break; 486 487 case DW_FORM_rnglistx: 488 OS << format("indexed (0x%x) rangelist = ", (uint32_t)UValue); 489 break; 490 491 // Should be formatted to 64-bit for DWARF64. 492 case DW_FORM_sec_offset: 493 AddrOS << format("0x%08x", (uint32_t)UValue); 494 break; 495 496 default: 497 OS << format("DW_FORM(0x%4.4x)", Form); 498 break; 499 } 500 501 if (CURelativeOffset) { 502 if (DumpOpts.Verbose) 503 OS << " => {"; 504 WithColor(OS, HighlightColor::Address).get() 505 << format("0x%8.8" PRIx64, UValue + (U ? U->getOffset() : 0)); 506 if (DumpOpts.Verbose) 507 OS << "}"; 508 } 509 } 510 511 void DWARFFormValue::dumpString(raw_ostream &OS) const { 512 Optional<const char *> DbgStr = getAsCString(); 513 if (DbgStr.hasValue()) { 514 auto COS = WithColor(OS, HighlightColor::String); 515 COS.get() << '"'; 516 COS.get().write_escaped(DbgStr.getValue()); 517 COS.get() << '"'; 518 } 519 } 520 521 Optional<const char *> DWARFFormValue::getAsCString() const { 522 if (!isFormClass(FC_String)) 523 return None; 524 if (Form == DW_FORM_string) 525 return Value.cstr; 526 // FIXME: Add support for DW_FORM_GNU_strp_alt 527 if (Form == DW_FORM_GNU_strp_alt || C == nullptr) 528 return None; 529 uint32_t Offset = Value.uval; 530 if (Form == DW_FORM_line_strp) { 531 // .debug_line_str is tracked in the Context. 532 if (const char *Str = C->getLineStringExtractor().getCStr(&Offset)) 533 return Str; 534 return None; 535 } 536 if (Form == DW_FORM_GNU_str_index || Form == DW_FORM_strx || 537 Form == DW_FORM_strx1 || Form == DW_FORM_strx2 || Form == DW_FORM_strx3 || 538 Form == DW_FORM_strx4) { 539 uint64_t StrOffset; 540 if (!U || !U->getStringOffsetSectionItem(Offset, StrOffset)) 541 return None; 542 Offset = StrOffset; 543 } 544 // Prefer the Unit's string extractor, because for .dwo it will point to 545 // .debug_str.dwo, while the Context's extractor always uses .debug_str. 546 if (U) { 547 if (const char *Str = U->getStringExtractor().getCStr(&Offset)) 548 return Str; 549 return None; 550 } 551 if (const char *Str = C->getStringExtractor().getCStr(&Offset)) 552 return Str; 553 return None; 554 } 555 556 Optional<uint64_t> DWARFFormValue::getAsAddress() const { 557 if (!isFormClass(FC_Address)) 558 return None; 559 if (Form == DW_FORM_GNU_addr_index) { 560 uint32_t Index = Value.uval; 561 uint64_t Result; 562 if (!U || !U->getAddrOffsetSectionItem(Index, Result)) 563 return None; 564 return Result; 565 } 566 return Value.uval; 567 } 568 569 Optional<uint64_t> DWARFFormValue::getAsReference() const { 570 if (!isFormClass(FC_Reference)) 571 return None; 572 switch (Form) { 573 case DW_FORM_ref1: 574 case DW_FORM_ref2: 575 case DW_FORM_ref4: 576 case DW_FORM_ref8: 577 case DW_FORM_ref_udata: 578 if (!U) 579 return None; 580 return Value.uval + U->getOffset(); 581 case DW_FORM_ref_addr: 582 case DW_FORM_ref_sig8: 583 case DW_FORM_GNU_ref_alt: 584 return Value.uval; 585 default: 586 return None; 587 } 588 } 589 590 Optional<uint64_t> DWARFFormValue::getAsSectionOffset() const { 591 if (!isFormClass(FC_SectionOffset)) 592 return None; 593 return Value.uval; 594 } 595 596 Optional<uint64_t> DWARFFormValue::getAsUnsignedConstant() const { 597 if ((!isFormClass(FC_Constant) && !isFormClass(FC_Flag)) || 598 Form == DW_FORM_sdata) 599 return None; 600 return Value.uval; 601 } 602 603 Optional<int64_t> DWARFFormValue::getAsSignedConstant() const { 604 if ((!isFormClass(FC_Constant) && !isFormClass(FC_Flag)) || 605 (Form == DW_FORM_udata && 606 uint64_t(std::numeric_limits<int64_t>::max()) < Value.uval)) 607 return None; 608 switch (Form) { 609 case DW_FORM_data4: 610 return int32_t(Value.uval); 611 case DW_FORM_data2: 612 return int16_t(Value.uval); 613 case DW_FORM_data1: 614 return int8_t(Value.uval); 615 case DW_FORM_sdata: 616 case DW_FORM_data8: 617 default: 618 return Value.sval; 619 } 620 } 621 622 Optional<ArrayRef<uint8_t>> DWARFFormValue::getAsBlock() const { 623 if (!isFormClass(FC_Block) && !isFormClass(FC_Exprloc) && 624 Form != DW_FORM_data16) 625 return None; 626 return makeArrayRef(Value.data, Value.uval); 627 } 628 629 Optional<uint64_t> DWARFFormValue::getAsCStringOffset() const { 630 if (!isFormClass(FC_String) && Form == DW_FORM_string) 631 return None; 632 return Value.uval; 633 } 634 635 Optional<uint64_t> DWARFFormValue::getAsReferenceUVal() const { 636 if (!isFormClass(FC_Reference)) 637 return None; 638 return Value.uval; 639 } 640
