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 "SyntaxHighlighting.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/DebugInfo/DWARF/DWARFContext.h" 16 #include "llvm/DebugInfo/DWARF/DWARFFormValue.h" 17 #include "llvm/DebugInfo/DWARF/DWARFRelocMap.h" 18 #include "llvm/DebugInfo/DWARF/DWARFUnit.h" 19 #include "llvm/Support/Dwarf.h" 20 #include "llvm/Support/ErrorHandling.h" 21 #include "llvm/Support/Format.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 using namespace syntax; 30 31 static const DWARFFormValue::FormClass DWARF4FormClasses[] = { 32 DWARFFormValue::FC_Unknown, // 0x0 33 DWARFFormValue::FC_Address, // 0x01 DW_FORM_addr 34 DWARFFormValue::FC_Unknown, // 0x02 unused 35 DWARFFormValue::FC_Block, // 0x03 DW_FORM_block2 36 DWARFFormValue::FC_Block, // 0x04 DW_FORM_block4 37 DWARFFormValue::FC_Constant, // 0x05 DW_FORM_data2 38 // --- These can be FC_SectionOffset in DWARF3 and below: 39 DWARFFormValue::FC_Constant, // 0x06 DW_FORM_data4 40 DWARFFormValue::FC_Constant, // 0x07 DW_FORM_data8 41 // --- 42 DWARFFormValue::FC_String, // 0x08 DW_FORM_string 43 DWARFFormValue::FC_Block, // 0x09 DW_FORM_block 44 DWARFFormValue::FC_Block, // 0x0a DW_FORM_block1 45 DWARFFormValue::FC_Constant, // 0x0b DW_FORM_data1 46 DWARFFormValue::FC_Flag, // 0x0c DW_FORM_flag 47 DWARFFormValue::FC_Constant, // 0x0d DW_FORM_sdata 48 DWARFFormValue::FC_String, // 0x0e DW_FORM_strp 49 DWARFFormValue::FC_Constant, // 0x0f DW_FORM_udata 50 DWARFFormValue::FC_Reference, // 0x10 DW_FORM_ref_addr 51 DWARFFormValue::FC_Reference, // 0x11 DW_FORM_ref1 52 DWARFFormValue::FC_Reference, // 0x12 DW_FORM_ref2 53 DWARFFormValue::FC_Reference, // 0x13 DW_FORM_ref4 54 DWARFFormValue::FC_Reference, // 0x14 DW_FORM_ref8 55 DWARFFormValue::FC_Reference, // 0x15 DW_FORM_ref_udata 56 DWARFFormValue::FC_Indirect, // 0x16 DW_FORM_indirect 57 DWARFFormValue::FC_SectionOffset, // 0x17 DW_FORM_sec_offset 58 DWARFFormValue::FC_Exprloc, // 0x18 DW_FORM_exprloc 59 DWARFFormValue::FC_Flag, // 0x19 DW_FORM_flag_present 60 }; 61 62 namespace { 63 64 /// A helper class that can be used in DWARFFormValue.cpp functions that need 65 /// to know the byte size of DW_FORM values that vary in size depending on the 66 /// DWARF version, address byte size, or DWARF32 or DWARF64. 67 class FormSizeHelper { 68 uint16_t Version; 69 uint8_t AddrSize; 70 llvm::dwarf::DwarfFormat Format; 71 72 public: 73 FormSizeHelper(uint16_t V, uint8_t A, llvm::dwarf::DwarfFormat F) 74 : Version(V), AddrSize(A), Format(F) {} 75 76 uint8_t getAddressByteSize() const { return AddrSize; } 77 78 uint8_t getRefAddrByteSize() const { 79 if (Version == 2) 80 return AddrSize; 81 return getDwarfOffsetByteSize(); 82 } 83 84 uint8_t getDwarfOffsetByteSize() const { 85 switch (Format) { 86 case dwarf::DwarfFormat::DWARF32: 87 return 4; 88 case dwarf::DwarfFormat::DWARF64: 89 return 8; 90 } 91 llvm_unreachable("Invalid Format value"); 92 } 93 }; 94 95 } // end anonymous namespace 96 97 template <class T> 98 static Optional<uint8_t> getFixedByteSize(dwarf::Form Form, const T *U) { 99 switch (Form) { 100 case DW_FORM_addr: 101 if (U) 102 return U->getAddressByteSize(); 103 return None; 104 105 case DW_FORM_block: // ULEB128 length L followed by L bytes. 106 case DW_FORM_block1: // 1 byte length L followed by L bytes. 107 case DW_FORM_block2: // 2 byte length L followed by L bytes. 108 case DW_FORM_block4: // 4 byte length L followed by L bytes. 109 case DW_FORM_string: // C-string with null terminator. 110 case DW_FORM_sdata: // SLEB128. 111 case DW_FORM_udata: // ULEB128. 112 case DW_FORM_ref_udata: // ULEB128. 113 case DW_FORM_indirect: // ULEB128. 114 case DW_FORM_exprloc: // ULEB128 length L followed by L bytes. 115 case DW_FORM_strx: // ULEB128. 116 case DW_FORM_addrx: // ULEB128. 117 case DW_FORM_loclistx: // ULEB128. 118 case DW_FORM_rnglistx: // ULEB128. 119 case DW_FORM_GNU_addr_index: // ULEB128. 120 case DW_FORM_GNU_str_index: // ULEB128. 121 return None; 122 123 case DW_FORM_ref_addr: 124 if (U) 125 return U->getRefAddrByteSize(); 126 return None; 127 128 case DW_FORM_flag: 129 case DW_FORM_data1: 130 case DW_FORM_ref1: 131 case DW_FORM_strx1: 132 case DW_FORM_addrx1: 133 return 1; 134 135 case DW_FORM_data2: 136 case DW_FORM_ref2: 137 case DW_FORM_strx2: 138 case DW_FORM_addrx2: 139 return 2; 140 141 case DW_FORM_data4: 142 case DW_FORM_ref4: 143 case DW_FORM_ref_sup4: 144 case DW_FORM_strx4: 145 case DW_FORM_addrx4: 146 return 4; 147 148 case DW_FORM_strp: 149 case DW_FORM_GNU_ref_alt: 150 case DW_FORM_GNU_strp_alt: 151 case DW_FORM_line_strp: 152 case DW_FORM_sec_offset: 153 case DW_FORM_strp_sup: 154 if (U) 155 return U->getDwarfOffsetByteSize(); 156 return None; 157 158 case DW_FORM_data8: 159 case DW_FORM_ref8: 160 case DW_FORM_ref_sig8: 161 case DW_FORM_ref_sup8: 162 return 8; 163 164 case DW_FORM_flag_present: 165 return 0; 166 167 case DW_FORM_data16: 168 return 16; 169 170 case DW_FORM_implicit_const: 171 // The implicit value is stored in the abbreviation as a SLEB128, and 172 // there no data in debug info. 173 return 0; 174 175 default: 176 llvm_unreachable("Handle this form in this switch statement"); 177 } 178 return None; 179 } 180 181 template <class T> 182 static bool skipFormValue(dwarf::Form Form, const DataExtractor &DebugInfoData, 183 uint32_t *OffsetPtr, const T *U) { 184 bool Indirect = false; 185 do { 186 switch (Form) { 187 // Blocks of inlined data that have a length field and the data bytes 188 // inlined in the .debug_info. 189 case DW_FORM_exprloc: 190 case DW_FORM_block: { 191 uint64_t size = DebugInfoData.getULEB128(OffsetPtr); 192 *OffsetPtr += size; 193 return true; 194 } 195 case DW_FORM_block1: { 196 uint8_t size = DebugInfoData.getU8(OffsetPtr); 197 *OffsetPtr += size; 198 return true; 199 } 200 case DW_FORM_block2: { 201 uint16_t size = DebugInfoData.getU16(OffsetPtr); 202 *OffsetPtr += size; 203 return true; 204 } 205 case DW_FORM_block4: { 206 uint32_t size = DebugInfoData.getU32(OffsetPtr); 207 *OffsetPtr += size; 208 return true; 209 } 210 211 // Inlined NULL terminated C-strings. 212 case DW_FORM_string: 213 DebugInfoData.getCStr(OffsetPtr); 214 return true; 215 216 case DW_FORM_addr: 217 case DW_FORM_ref_addr: 218 case DW_FORM_flag_present: 219 case DW_FORM_data1: 220 case DW_FORM_data2: 221 case DW_FORM_data4: 222 case DW_FORM_data8: 223 case DW_FORM_flag: 224 case DW_FORM_ref1: 225 case DW_FORM_ref2: 226 case DW_FORM_ref4: 227 case DW_FORM_ref8: 228 case DW_FORM_ref_sig8: 229 case DW_FORM_ref_sup4: 230 case DW_FORM_ref_sup8: 231 case DW_FORM_strx1: 232 case DW_FORM_strx2: 233 case DW_FORM_strx4: 234 case DW_FORM_addrx1: 235 case DW_FORM_addrx2: 236 case DW_FORM_addrx4: 237 case DW_FORM_sec_offset: 238 case DW_FORM_strp: 239 case DW_FORM_strp_sup: 240 case DW_FORM_line_strp: 241 case DW_FORM_GNU_ref_alt: 242 case DW_FORM_GNU_strp_alt: 243 if (Optional<uint8_t> FixedSize = ::getFixedByteSize(Form, U)) { 244 *OffsetPtr += *FixedSize; 245 return true; 246 } 247 return false; 248 249 // signed or unsigned LEB 128 values. 250 case DW_FORM_sdata: 251 DebugInfoData.getSLEB128(OffsetPtr); 252 return true; 253 254 case DW_FORM_udata: 255 case DW_FORM_ref_udata: 256 case DW_FORM_strx: 257 case DW_FORM_addrx: 258 case DW_FORM_loclistx: 259 case DW_FORM_rnglistx: 260 case DW_FORM_GNU_addr_index: 261 case DW_FORM_GNU_str_index: 262 DebugInfoData.getULEB128(OffsetPtr); 263 return true; 264 265 case DW_FORM_indirect: 266 Indirect = true; 267 Form = static_cast<dwarf::Form>(DebugInfoData.getULEB128(OffsetPtr)); 268 break; 269 270 default: 271 return false; 272 } 273 } while (Indirect); 274 return true; 275 } 276 277 Optional<uint8_t> DWARFFormValue::getFixedByteSize(dwarf::Form Form, 278 const DWARFUnit *U) { 279 return ::getFixedByteSize(Form, U); 280 } 281 282 Optional<uint8_t> 283 DWARFFormValue::getFixedByteSize(dwarf::Form Form, uint16_t Version, 284 uint8_t AddrSize, 285 llvm::dwarf::DwarfFormat Format) { 286 FormSizeHelper FSH(Version, AddrSize, Format); 287 return ::getFixedByteSize(Form, &FSH); 288 } 289 290 bool DWARFFormValue::isFormClass(DWARFFormValue::FormClass FC) const { 291 // First, check DWARF4 form classes. 292 if (Form < makeArrayRef(DWARF4FormClasses).size() && 293 DWARF4FormClasses[Form] == FC) 294 return true; 295 // Check more forms from DWARF4 and DWARF5 proposals. 296 switch (Form) { 297 case DW_FORM_ref_sig8: 298 case DW_FORM_GNU_ref_alt: 299 return (FC == FC_Reference); 300 case DW_FORM_GNU_addr_index: 301 return (FC == FC_Address); 302 case DW_FORM_GNU_str_index: 303 case DW_FORM_GNU_strp_alt: 304 return (FC == FC_String); 305 case DW_FORM_implicit_const: 306 return (FC == FC_Constant); 307 default: 308 break; 309 } 310 // In DWARF3 DW_FORM_data4 and DW_FORM_data8 served also as a section offset. 311 // Don't check for DWARF version here, as some producers may still do this 312 // by mistake. 313 return (Form == DW_FORM_data4 || Form == DW_FORM_data8) && 314 FC == FC_SectionOffset; 315 } 316 317 bool DWARFFormValue::extractValue(const DataExtractor &data, 318 uint32_t *offset_ptr, 319 const DWARFUnit *cu) { 320 U = cu; 321 bool indirect = false; 322 bool is_block = false; 323 Value.data = nullptr; 324 // Read the value for the form into value and follow and DW_FORM_indirect 325 // instances we run into 326 do { 327 indirect = false; 328 switch (Form) { 329 case DW_FORM_addr: 330 case DW_FORM_ref_addr: { 331 if (!U) 332 return false; 333 uint16_t AddrSize = 334 (Form == DW_FORM_addr) 335 ? U->getAddressByteSize() 336 : U->getRefAddrByteSize(); 337 RelocAddrMap::const_iterator AI = U->getRelocMap()->find(*offset_ptr); 338 if (AI != U->getRelocMap()->end()) { 339 Value.uval = data.getUnsigned(offset_ptr, AddrSize) + AI->second.second; 340 } else 341 Value.uval = data.getUnsigned(offset_ptr, AddrSize); 342 break; 343 } 344 case DW_FORM_exprloc: 345 case DW_FORM_block: 346 Value.uval = data.getULEB128(offset_ptr); 347 is_block = true; 348 break; 349 case DW_FORM_block1: 350 Value.uval = data.getU8(offset_ptr); 351 is_block = true; 352 break; 353 case DW_FORM_block2: 354 Value.uval = data.getU16(offset_ptr); 355 is_block = true; 356 break; 357 case DW_FORM_block4: 358 Value.uval = data.getU32(offset_ptr); 359 is_block = true; 360 break; 361 case DW_FORM_data1: 362 case DW_FORM_ref1: 363 case DW_FORM_flag: 364 case DW_FORM_strx1: 365 case DW_FORM_addrx1: 366 Value.uval = data.getU8(offset_ptr); 367 break; 368 case DW_FORM_data2: 369 case DW_FORM_ref2: 370 case DW_FORM_strx2: 371 case DW_FORM_addrx2: 372 Value.uval = data.getU16(offset_ptr); 373 break; 374 case DW_FORM_data4: 375 case DW_FORM_ref4: 376 case DW_FORM_ref_sup4: 377 case DW_FORM_strx4: 378 case DW_FORM_addrx4: { 379 Value.uval = data.getU32(offset_ptr); 380 if (!U) 381 break; 382 RelocAddrMap::const_iterator AI = U->getRelocMap()->find(*offset_ptr-4); 383 if (AI != U->getRelocMap()->end()) 384 Value.uval += AI->second.second; 385 break; 386 } 387 case DW_FORM_data8: 388 case DW_FORM_ref8: 389 case DW_FORM_ref_sup8: 390 Value.uval = data.getU64(offset_ptr); 391 break; 392 case DW_FORM_sdata: 393 Value.sval = data.getSLEB128(offset_ptr); 394 break; 395 case DW_FORM_udata: 396 case DW_FORM_ref_udata: 397 Value.uval = data.getULEB128(offset_ptr); 398 break; 399 case DW_FORM_string: 400 Value.cstr = data.getCStr(offset_ptr); 401 break; 402 case DW_FORM_indirect: 403 Form = static_cast<dwarf::Form>(data.getULEB128(offset_ptr)); 404 indirect = true; 405 break; 406 case DW_FORM_strp: 407 case DW_FORM_sec_offset: 408 case DW_FORM_GNU_ref_alt: 409 case DW_FORM_GNU_strp_alt: 410 case DW_FORM_line_strp: 411 case DW_FORM_strp_sup: { 412 if (!U) 413 return false; 414 RelocAddrMap::const_iterator AI = U->getRelocMap()->find(*offset_ptr); 415 uint8_t Size = U->getDwarfOffsetByteSize(); 416 Value.uval = data.getUnsigned(offset_ptr, Size); 417 if (AI != U->getRelocMap()->end()) 418 Value.uval += AI->second.second; 419 break; 420 } 421 case DW_FORM_flag_present: 422 Value.uval = 1; 423 break; 424 case DW_FORM_ref_sig8: 425 Value.uval = data.getU64(offset_ptr); 426 break; 427 case DW_FORM_GNU_addr_index: 428 case DW_FORM_GNU_str_index: 429 Value.uval = data.getULEB128(offset_ptr); 430 break; 431 default: 432 // DWARFFormValue::skipValue() will have caught this and caused all 433 // DWARF DIEs to fail to be parsed, so this code is not be reachable. 434 llvm_unreachable("unsupported form"); 435 } 436 } while (indirect); 437 438 if (is_block) { 439 StringRef str = data.getData().substr(*offset_ptr, Value.uval); 440 Value.data = nullptr; 441 if (!str.empty()) { 442 Value.data = reinterpret_cast<const uint8_t *>(str.data()); 443 *offset_ptr += Value.uval; 444 } 445 } 446 447 return true; 448 } 449 450 bool DWARFFormValue::skipValue(DataExtractor DebugInfoData, 451 uint32_t *offset_ptr, const DWARFUnit *U) const { 452 return DWARFFormValue::skipValue(Form, DebugInfoData, offset_ptr, U); 453 } 454 455 bool DWARFFormValue::skipValue(dwarf::Form form, DataExtractor DebugInfoData, 456 uint32_t *offset_ptr, const DWARFUnit *U) { 457 return skipFormValue(form, DebugInfoData, offset_ptr, U); 458 } 459 460 bool DWARFFormValue::skipValue(dwarf::Form form, DataExtractor DebugInfoData, 461 uint32_t *offset_ptr, uint16_t Version, 462 uint8_t AddrSize, 463 llvm::dwarf::DwarfFormat Format) { 464 FormSizeHelper FSH(Version, AddrSize, Format); 465 return skipFormValue(form, DebugInfoData, offset_ptr, &FSH); 466 } 467 468 void 469 DWARFFormValue::dump(raw_ostream &OS) const { 470 uint64_t uvalue = Value.uval; 471 bool cu_relative_offset = false; 472 473 switch (Form) { 474 case DW_FORM_addr: OS << format("0x%016" PRIx64, uvalue); break; 475 case DW_FORM_GNU_addr_index: { 476 OS << format(" indexed (%8.8x) address = ", (uint32_t)uvalue); 477 uint64_t Address; 478 if (U == nullptr) 479 OS << "<invalid dwarf unit>"; 480 else if (U->getAddrOffsetSectionItem(uvalue, Address)) 481 OS << format("0x%016" PRIx64, Address); 482 else 483 OS << "<no .debug_addr section>"; 484 break; 485 } 486 case DW_FORM_flag_present: OS << "true"; break; 487 case DW_FORM_flag: 488 case DW_FORM_data1: OS << format("0x%02x", (uint8_t)uvalue); break; 489 case DW_FORM_data2: OS << format("0x%04x", (uint16_t)uvalue); break; 490 case DW_FORM_data4: OS << format("0x%08x", (uint32_t)uvalue); break; 491 case DW_FORM_ref_sig8: 492 case DW_FORM_data8: OS << format("0x%016" PRIx64, uvalue); break; 493 case DW_FORM_string: 494 OS << '"'; 495 OS.write_escaped(Value.cstr); 496 OS << '"'; 497 break; 498 case DW_FORM_exprloc: 499 case DW_FORM_block: 500 case DW_FORM_block1: 501 case DW_FORM_block2: 502 case DW_FORM_block4: 503 if (uvalue > 0) { 504 switch (Form) { 505 case DW_FORM_exprloc: 506 case DW_FORM_block: OS << format("<0x%" PRIx64 "> ", uvalue); break; 507 case DW_FORM_block1: OS << format("<0x%2.2x> ", (uint8_t)uvalue); break; 508 case DW_FORM_block2: OS << format("<0x%4.4x> ", (uint16_t)uvalue); break; 509 case DW_FORM_block4: OS << format("<0x%8.8x> ", (uint32_t)uvalue); break; 510 default: break; 511 } 512 513 const uint8_t* data_ptr = Value.data; 514 if (data_ptr) { 515 // uvalue contains size of block 516 const uint8_t* end_data_ptr = data_ptr + uvalue; 517 while (data_ptr < end_data_ptr) { 518 OS << format("%2.2x ", *data_ptr); 519 ++data_ptr; 520 } 521 } 522 else 523 OS << "NULL"; 524 } 525 break; 526 527 case DW_FORM_sdata: OS << Value.sval; break; 528 case DW_FORM_udata: OS << Value.uval; break; 529 case DW_FORM_strp: 530 OS << format(" .debug_str[0x%8.8x] = ", (uint32_t)uvalue); 531 dumpString(OS); 532 break; 533 case DW_FORM_GNU_str_index: 534 OS << format(" indexed (%8.8x) string = ", (uint32_t)uvalue); 535 dumpString(OS); 536 break; 537 case DW_FORM_GNU_strp_alt: 538 OS << format("alt indirect string, offset: 0x%" PRIx64 "", uvalue); 539 dumpString(OS); 540 break; 541 case DW_FORM_ref_addr: 542 OS << format("0x%016" PRIx64, uvalue); 543 break; 544 case DW_FORM_ref1: 545 cu_relative_offset = true; 546 OS << format("cu + 0x%2.2x", (uint8_t)uvalue); 547 break; 548 case DW_FORM_ref2: 549 cu_relative_offset = true; 550 OS << format("cu + 0x%4.4x", (uint16_t)uvalue); 551 break; 552 case DW_FORM_ref4: 553 cu_relative_offset = true; 554 OS << format("cu + 0x%4.4x", (uint32_t)uvalue); 555 break; 556 case DW_FORM_ref8: 557 cu_relative_offset = true; 558 OS << format("cu + 0x%8.8" PRIx64, uvalue); 559 break; 560 case DW_FORM_ref_udata: 561 cu_relative_offset = true; 562 OS << format("cu + 0x%" PRIx64, uvalue); 563 break; 564 case DW_FORM_GNU_ref_alt: 565 OS << format("<alt 0x%" PRIx64 ">", uvalue); 566 break; 567 568 // All DW_FORM_indirect attributes should be resolved prior to calling 569 // this function 570 case DW_FORM_indirect: 571 OS << "DW_FORM_indirect"; 572 break; 573 574 // Should be formatted to 64-bit for DWARF64. 575 case DW_FORM_sec_offset: 576 OS << format("0x%08x", (uint32_t)uvalue); 577 break; 578 579 default: 580 OS << format("DW_FORM(0x%4.4x)", Form); 581 break; 582 } 583 584 if (cu_relative_offset) { 585 OS << " => {"; 586 WithColor(OS, syntax::Address).get() 587 << format("0x%8.8" PRIx64, uvalue + (U ? U->getOffset() : 0)); 588 OS << "}"; 589 } 590 } 591 592 void DWARFFormValue::dumpString(raw_ostream &OS) const { 593 Optional<const char *> DbgStr = getAsCString(); 594 if (DbgStr.hasValue()) { 595 raw_ostream &COS = WithColor(OS, syntax::String); 596 COS << '"'; 597 COS.write_escaped(DbgStr.getValue()); 598 COS << '"'; 599 } 600 } 601 602 Optional<const char *> DWARFFormValue::getAsCString() const { 603 if (!isFormClass(FC_String)) 604 return None; 605 if (Form == DW_FORM_string) 606 return Value.cstr; 607 // FIXME: Add support for DW_FORM_GNU_strp_alt 608 if (Form == DW_FORM_GNU_strp_alt || U == nullptr) 609 return None; 610 uint32_t Offset = Value.uval; 611 if (Form == DW_FORM_GNU_str_index) { 612 uint32_t StrOffset; 613 if (!U->getStringOffsetSectionItem(Offset, StrOffset)) 614 return None; 615 Offset = StrOffset; 616 } 617 if (const char *Str = U->getStringExtractor().getCStr(&Offset)) { 618 return Str; 619 } 620 return None; 621 } 622 623 Optional<uint64_t> DWARFFormValue::getAsAddress() const { 624 if (!isFormClass(FC_Address)) 625 return None; 626 if (Form == DW_FORM_GNU_addr_index) { 627 uint32_t Index = Value.uval; 628 uint64_t Result; 629 if (!U || !U->getAddrOffsetSectionItem(Index, Result)) 630 return None; 631 return Result; 632 } 633 return Value.uval; 634 } 635 636 Optional<uint64_t> DWARFFormValue::getAsReference() const { 637 if (!isFormClass(FC_Reference)) 638 return None; 639 switch (Form) { 640 case DW_FORM_ref1: 641 case DW_FORM_ref2: 642 case DW_FORM_ref4: 643 case DW_FORM_ref8: 644 case DW_FORM_ref_udata: 645 if (!U) 646 return None; 647 return Value.uval + U->getOffset(); 648 case DW_FORM_ref_addr: 649 case DW_FORM_ref_sig8: 650 case DW_FORM_GNU_ref_alt: 651 return Value.uval; 652 default: 653 return None; 654 } 655 } 656 657 Optional<uint64_t> DWARFFormValue::getAsSectionOffset() const { 658 if (!isFormClass(FC_SectionOffset)) 659 return None; 660 return Value.uval; 661 } 662 663 Optional<uint64_t> DWARFFormValue::getAsUnsignedConstant() const { 664 if ((!isFormClass(FC_Constant) && !isFormClass(FC_Flag)) 665 || Form == DW_FORM_sdata) 666 return None; 667 return Value.uval; 668 } 669 670 Optional<int64_t> DWARFFormValue::getAsSignedConstant() const { 671 if ((!isFormClass(FC_Constant) && !isFormClass(FC_Flag)) || 672 (Form == DW_FORM_udata && uint64_t(std::numeric_limits<int64_t>::max()) < Value.uval)) 673 return None; 674 switch (Form) { 675 case DW_FORM_data4: 676 return int32_t(Value.uval); 677 case DW_FORM_data2: 678 return int16_t(Value.uval); 679 case DW_FORM_data1: 680 return int8_t(Value.uval); 681 case DW_FORM_sdata: 682 case DW_FORM_data8: 683 default: 684 return Value.sval; 685 } 686 } 687 688 Optional<ArrayRef<uint8_t>> DWARFFormValue::getAsBlock() const { 689 if (!isFormClass(FC_Block) && !isFormClass(FC_Exprloc)) 690 return None; 691 return makeArrayRef(Value.data, Value.uval); 692 } 693 694 Optional<uint64_t> DWARFFormValue::getAsCStringOffset() const { 695 if (!isFormClass(FC_String) && Form == DW_FORM_string) 696 return None; 697 return Value.uval; 698 } 699 700 Optional<uint64_t> DWARFFormValue::getAsReferenceUVal() const { 701 if (!isFormClass(FC_Reference)) 702 return None; 703 return Value.uval; 704 } 705