DWARFFormValue.cpp revision 360784
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 26using namespace llvm; 27using namespace dwarf; 28 29static 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 80DWARFFormValue DWARFFormValue::createFromSValue(dwarf::Form F, int64_t V) { 81 return DWARFFormValue(F, ValueType(V)); 82} 83 84DWARFFormValue DWARFFormValue::createFromUValue(dwarf::Form F, uint64_t V) { 85 return DWARFFormValue(F, ValueType(V)); 86} 87 88DWARFFormValue DWARFFormValue::createFromPValue(dwarf::Form F, const char *V) { 89 return DWARFFormValue(F, ValueType(V)); 90} 91 92DWARFFormValue 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 100DWARFFormValue 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 108bool 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 206bool 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 236bool 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 bool Indirect = false; 245 bool IsBlock = false; 246 Value.data = nullptr; 247 // Read the value for the form into value and follow and DW_FORM_indirect 248 // instances we run into 249 do { 250 Indirect = false; 251 switch (Form) { 252 case DW_FORM_addr: 253 case DW_FORM_ref_addr: { 254 uint16_t Size = 255 (Form == DW_FORM_addr) ? FP.AddrSize : FP.getRefAddrByteSize(); 256 Value.uval = Data.getRelocatedValue(Size, OffsetPtr, &Value.SectionIndex); 257 break; 258 } 259 case DW_FORM_exprloc: 260 case DW_FORM_block: 261 Value.uval = Data.getULEB128(OffsetPtr); 262 IsBlock = true; 263 break; 264 case DW_FORM_block1: 265 Value.uval = Data.getU8(OffsetPtr); 266 IsBlock = true; 267 break; 268 case DW_FORM_block2: 269 Value.uval = Data.getU16(OffsetPtr); 270 IsBlock = true; 271 break; 272 case DW_FORM_block4: 273 Value.uval = Data.getU32(OffsetPtr); 274 IsBlock = true; 275 break; 276 case DW_FORM_data1: 277 case DW_FORM_ref1: 278 case DW_FORM_flag: 279 case DW_FORM_strx1: 280 case DW_FORM_addrx1: 281 Value.uval = Data.getU8(OffsetPtr); 282 break; 283 case DW_FORM_data2: 284 case DW_FORM_ref2: 285 case DW_FORM_strx2: 286 case DW_FORM_addrx2: 287 Value.uval = Data.getU16(OffsetPtr); 288 break; 289 case DW_FORM_strx3: 290 Value.uval = Data.getU24(OffsetPtr); 291 break; 292 case DW_FORM_data4: 293 case DW_FORM_ref4: 294 case DW_FORM_ref_sup4: 295 case DW_FORM_strx4: 296 case DW_FORM_addrx4: 297 Value.uval = Data.getRelocatedValue(4, OffsetPtr); 298 break; 299 case DW_FORM_data8: 300 case DW_FORM_ref8: 301 case DW_FORM_ref_sup8: 302 Value.uval = Data.getRelocatedValue(8, OffsetPtr); 303 break; 304 case DW_FORM_data16: 305 // Treat this like a 16-byte block. 306 Value.uval = 16; 307 IsBlock = true; 308 break; 309 case DW_FORM_sdata: 310 Value.sval = Data.getSLEB128(OffsetPtr); 311 break; 312 case DW_FORM_udata: 313 case DW_FORM_ref_udata: 314 case DW_FORM_rnglistx: 315 case DW_FORM_loclistx: 316 Value.uval = Data.getULEB128(OffsetPtr); 317 break; 318 case DW_FORM_string: 319 Value.cstr = Data.getCStr(OffsetPtr); 320 break; 321 case DW_FORM_indirect: 322 Form = static_cast<dwarf::Form>(Data.getULEB128(OffsetPtr)); 323 Indirect = true; 324 break; 325 case DW_FORM_strp: 326 case DW_FORM_sec_offset: 327 case DW_FORM_GNU_ref_alt: 328 case DW_FORM_GNU_strp_alt: 329 case DW_FORM_line_strp: 330 case DW_FORM_strp_sup: { 331 Value.uval = 332 Data.getRelocatedValue(FP.getDwarfOffsetByteSize(), OffsetPtr); 333 break; 334 } 335 case DW_FORM_flag_present: 336 Value.uval = 1; 337 break; 338 case DW_FORM_ref_sig8: 339 Value.uval = Data.getU64(OffsetPtr); 340 break; 341 case DW_FORM_GNU_addr_index: 342 case DW_FORM_GNU_str_index: 343 case DW_FORM_addrx: 344 case DW_FORM_strx: 345 Value.uval = Data.getULEB128(OffsetPtr); 346 break; 347 default: 348 // DWARFFormValue::skipValue() will have caught this and caused all 349 // DWARF DIEs to fail to be parsed, so this code is not be reachable. 350 llvm_unreachable("unsupported form"); 351 } 352 } while (Indirect); 353 354 if (IsBlock) { 355 StringRef Str = Data.getData().substr(*OffsetPtr, Value.uval); 356 Value.data = nullptr; 357 if (!Str.empty()) { 358 Value.data = Str.bytes_begin(); 359 *OffsetPtr += Value.uval; 360 } 361 } 362 363 return true; 364} 365 366void DWARFFormValue::dumpSectionedAddress(raw_ostream &OS, 367 DIDumpOptions DumpOpts, 368 object::SectionedAddress SA) const { 369 OS << format("0x%016" PRIx64, SA.Address); 370 dumpAddressSection(U->getContext().getDWARFObj(), OS, DumpOpts, 371 SA.SectionIndex); 372} 373 374void DWARFFormValue::dumpAddressSection(const DWARFObject &Obj, raw_ostream &OS, 375 DIDumpOptions DumpOpts, 376 uint64_t SectionIndex) { 377 if (!DumpOpts.Verbose || SectionIndex == -1ULL) 378 return; 379 ArrayRef<SectionName> SectionNames = Obj.getSectionNames(); 380 const auto &SecRef = SectionNames[SectionIndex]; 381 382 OS << " \"" << SecRef.Name << '\"'; 383 384 // Print section index if name is not unique. 385 if (!SecRef.IsNameUnique) 386 OS << format(" [%" PRIu64 "]", SectionIndex); 387} 388 389void DWARFFormValue::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const { 390 uint64_t UValue = Value.uval; 391 bool CURelativeOffset = false; 392 raw_ostream &AddrOS = DumpOpts.ShowAddresses 393 ? WithColor(OS, HighlightColor::Address).get() 394 : nulls(); 395 switch (Form) { 396 case DW_FORM_addr: 397 dumpSectionedAddress(AddrOS, DumpOpts, {Value.uval, Value.SectionIndex}); 398 break; 399 case DW_FORM_addrx: 400 case DW_FORM_addrx1: 401 case DW_FORM_addrx2: 402 case DW_FORM_addrx3: 403 case DW_FORM_addrx4: 404 case DW_FORM_GNU_addr_index: { 405 if (U == nullptr) { 406 OS << "<invalid dwarf unit>"; 407 break; 408 } 409 Optional<object::SectionedAddress> A = U->getAddrOffsetSectionItem(UValue); 410 if (!A || DumpOpts.Verbose) 411 AddrOS << format("indexed (%8.8x) address = ", (uint32_t)UValue); 412 if (A) 413 dumpSectionedAddress(AddrOS, DumpOpts, *A); 414 else 415 OS << "<unresolved>"; 416 break; 417 } 418 case DW_FORM_flag_present: 419 OS << "true"; 420 break; 421 case DW_FORM_flag: 422 case DW_FORM_data1: 423 OS << format("0x%02x", (uint8_t)UValue); 424 break; 425 case DW_FORM_data2: 426 OS << format("0x%04x", (uint16_t)UValue); 427 break; 428 case DW_FORM_data4: 429 OS << format("0x%08x", (uint32_t)UValue); 430 break; 431 case DW_FORM_ref_sig8: 432 AddrOS << format("0x%016" PRIx64, UValue); 433 break; 434 case DW_FORM_data8: 435 OS << format("0x%016" PRIx64, UValue); 436 break; 437 case DW_FORM_data16: 438 OS << format_bytes(ArrayRef<uint8_t>(Value.data, 16), None, 16, 16); 439 break; 440 case DW_FORM_string: 441 OS << '"'; 442 OS.write_escaped(Value.cstr); 443 OS << '"'; 444 break; 445 case DW_FORM_exprloc: 446 case DW_FORM_block: 447 case DW_FORM_block1: 448 case DW_FORM_block2: 449 case DW_FORM_block4: 450 if (UValue > 0) { 451 switch (Form) { 452 case DW_FORM_exprloc: 453 case DW_FORM_block: 454 AddrOS << format("<0x%" PRIx64 "> ", UValue); 455 break; 456 case DW_FORM_block1: 457 AddrOS << format("<0x%2.2x> ", (uint8_t)UValue); 458 break; 459 case DW_FORM_block2: 460 AddrOS << format("<0x%4.4x> ", (uint16_t)UValue); 461 break; 462 case DW_FORM_block4: 463 AddrOS << format("<0x%8.8x> ", (uint32_t)UValue); 464 break; 465 default: 466 break; 467 } 468 469 const uint8_t *DataPtr = Value.data; 470 if (DataPtr) { 471 // UValue contains size of block 472 const uint8_t *EndDataPtr = DataPtr + UValue; 473 while (DataPtr < EndDataPtr) { 474 AddrOS << format("%2.2x ", *DataPtr); 475 ++DataPtr; 476 } 477 } else 478 OS << "NULL"; 479 } 480 break; 481 482 case DW_FORM_sdata: 483 OS << Value.sval; 484 break; 485 case DW_FORM_udata: 486 OS << Value.uval; 487 break; 488 case DW_FORM_strp: 489 if (DumpOpts.Verbose) 490 OS << format(" .debug_str[0x%8.8x] = ", (uint32_t)UValue); 491 dumpString(OS); 492 break; 493 case DW_FORM_line_strp: 494 if (DumpOpts.Verbose) 495 OS << format(" .debug_line_str[0x%8.8x] = ", (uint32_t)UValue); 496 dumpString(OS); 497 break; 498 case DW_FORM_strx: 499 case DW_FORM_strx1: 500 case DW_FORM_strx2: 501 case DW_FORM_strx3: 502 case DW_FORM_strx4: 503 case DW_FORM_GNU_str_index: 504 if (DumpOpts.Verbose) 505 OS << format("indexed (%8.8x) string = ", (uint32_t)UValue); 506 dumpString(OS); 507 break; 508 case DW_FORM_GNU_strp_alt: 509 if (DumpOpts.Verbose) 510 OS << format("alt indirect string, offset: 0x%" PRIx64 "", UValue); 511 dumpString(OS); 512 break; 513 case DW_FORM_ref_addr: 514 AddrOS << format("0x%016" PRIx64, UValue); 515 break; 516 case DW_FORM_ref1: 517 CURelativeOffset = true; 518 if (DumpOpts.Verbose) 519 AddrOS << format("cu + 0x%2.2x", (uint8_t)UValue); 520 break; 521 case DW_FORM_ref2: 522 CURelativeOffset = true; 523 if (DumpOpts.Verbose) 524 AddrOS << format("cu + 0x%4.4x", (uint16_t)UValue); 525 break; 526 case DW_FORM_ref4: 527 CURelativeOffset = true; 528 if (DumpOpts.Verbose) 529 AddrOS << format("cu + 0x%4.4x", (uint32_t)UValue); 530 break; 531 case DW_FORM_ref8: 532 CURelativeOffset = true; 533 if (DumpOpts.Verbose) 534 AddrOS << format("cu + 0x%8.8" PRIx64, UValue); 535 break; 536 case DW_FORM_ref_udata: 537 CURelativeOffset = true; 538 if (DumpOpts.Verbose) 539 AddrOS << format("cu + 0x%" PRIx64, UValue); 540 break; 541 case DW_FORM_GNU_ref_alt: 542 AddrOS << format("<alt 0x%" PRIx64 ">", UValue); 543 break; 544 545 // All DW_FORM_indirect attributes should be resolved prior to calling 546 // this function 547 case DW_FORM_indirect: 548 OS << "DW_FORM_indirect"; 549 break; 550 551 case DW_FORM_rnglistx: 552 OS << format("indexed (0x%x) rangelist = ", (uint32_t)UValue); 553 break; 554 555 case DW_FORM_loclistx: 556 OS << format("indexed (0x%x) loclist = ", (uint32_t)UValue); 557 break; 558 559 // Should be formatted to 64-bit for DWARF64. 560 case DW_FORM_sec_offset: 561 AddrOS << format("0x%08x", (uint32_t)UValue); 562 break; 563 564 default: 565 OS << format("DW_FORM(0x%4.4x)", Form); 566 break; 567 } 568 569 if (CURelativeOffset) { 570 if (DumpOpts.Verbose) 571 OS << " => {"; 572 if (DumpOpts.ShowAddresses) 573 WithColor(OS, HighlightColor::Address).get() 574 << format("0x%8.8" PRIx64, UValue + (U ? U->getOffset() : 0)); 575 if (DumpOpts.Verbose) 576 OS << "}"; 577 } 578} 579 580void DWARFFormValue::dumpString(raw_ostream &OS) const { 581 Optional<const char *> DbgStr = getAsCString(); 582 if (DbgStr.hasValue()) { 583 auto COS = WithColor(OS, HighlightColor::String); 584 COS.get() << '"'; 585 COS.get().write_escaped(DbgStr.getValue()); 586 COS.get() << '"'; 587 } 588} 589 590Optional<const char *> DWARFFormValue::getAsCString() const { 591 if (!isFormClass(FC_String)) 592 return None; 593 if (Form == DW_FORM_string) 594 return Value.cstr; 595 // FIXME: Add support for DW_FORM_GNU_strp_alt 596 if (Form == DW_FORM_GNU_strp_alt || C == nullptr) 597 return None; 598 uint64_t Offset = Value.uval; 599 if (Form == DW_FORM_line_strp) { 600 // .debug_line_str is tracked in the Context. 601 if (const char *Str = C->getLineStringExtractor().getCStr(&Offset)) 602 return Str; 603 return None; 604 } 605 if (Form == DW_FORM_GNU_str_index || Form == DW_FORM_strx || 606 Form == DW_FORM_strx1 || Form == DW_FORM_strx2 || Form == DW_FORM_strx3 || 607 Form == DW_FORM_strx4) { 608 if (!U) 609 return None; 610 Optional<uint64_t> StrOffset = U->getStringOffsetSectionItem(Offset); 611 if (!StrOffset) 612 return None; 613 Offset = *StrOffset; 614 } 615 // Prefer the Unit's string extractor, because for .dwo it will point to 616 // .debug_str.dwo, while the Context's extractor always uses .debug_str. 617 if (U) { 618 if (const char *Str = U->getStringExtractor().getCStr(&Offset)) 619 return Str; 620 return None; 621 } 622 if (const char *Str = C->getStringExtractor().getCStr(&Offset)) 623 return Str; 624 return None; 625} 626 627Optional<uint64_t> DWARFFormValue::getAsAddress() const { 628 if (auto SA = getAsSectionedAddress()) 629 return SA->Address; 630 return None; 631} 632 633Optional<object::SectionedAddress> 634DWARFFormValue::getAsSectionedAddress() const { 635 if (!isFormClass(FC_Address)) 636 return None; 637 if (Form == DW_FORM_GNU_addr_index || Form == DW_FORM_addrx) { 638 uint32_t Index = Value.uval; 639 if (!U) 640 return None; 641 Optional<object::SectionedAddress> SA = U->getAddrOffsetSectionItem(Index); 642 if (!SA) 643 return None; 644 return SA; 645 } 646 return {{Value.uval, Value.SectionIndex}}; 647} 648 649Optional<uint64_t> DWARFFormValue::getAsReference() const { 650 if (auto R = getAsRelativeReference()) 651 return R->Unit ? R->Unit->getOffset() + R->Offset : R->Offset; 652 return None; 653} 654 655Optional<DWARFFormValue::UnitOffset> DWARFFormValue::getAsRelativeReference() const { 656 if (!isFormClass(FC_Reference)) 657 return None; 658 switch (Form) { 659 case DW_FORM_ref1: 660 case DW_FORM_ref2: 661 case DW_FORM_ref4: 662 case DW_FORM_ref8: 663 case DW_FORM_ref_udata: 664 if (!U) 665 return None; 666 return UnitOffset{const_cast<DWARFUnit*>(U), Value.uval}; 667 case DW_FORM_ref_addr: 668 case DW_FORM_ref_sig8: 669 case DW_FORM_GNU_ref_alt: 670 return UnitOffset{nullptr, Value.uval}; 671 default: 672 return None; 673 } 674} 675 676Optional<uint64_t> DWARFFormValue::getAsSectionOffset() const { 677 if (!isFormClass(FC_SectionOffset)) 678 return None; 679 return Value.uval; 680} 681 682Optional<uint64_t> DWARFFormValue::getAsUnsignedConstant() const { 683 if ((!isFormClass(FC_Constant) && !isFormClass(FC_Flag)) || 684 Form == DW_FORM_sdata) 685 return None; 686 return Value.uval; 687} 688 689Optional<int64_t> DWARFFormValue::getAsSignedConstant() const { 690 if ((!isFormClass(FC_Constant) && !isFormClass(FC_Flag)) || 691 (Form == DW_FORM_udata && 692 uint64_t(std::numeric_limits<int64_t>::max()) < Value.uval)) 693 return None; 694 switch (Form) { 695 case DW_FORM_data4: 696 return int32_t(Value.uval); 697 case DW_FORM_data2: 698 return int16_t(Value.uval); 699 case DW_FORM_data1: 700 return int8_t(Value.uval); 701 case DW_FORM_sdata: 702 case DW_FORM_data8: 703 default: 704 return Value.sval; 705 } 706} 707 708Optional<ArrayRef<uint8_t>> DWARFFormValue::getAsBlock() const { 709 if (!isFormClass(FC_Block) && !isFormClass(FC_Exprloc) && 710 Form != DW_FORM_data16) 711 return None; 712 return makeArrayRef(Value.data, Value.uval); 713} 714 715Optional<uint64_t> DWARFFormValue::getAsCStringOffset() const { 716 if (!isFormClass(FC_String) && Form == DW_FORM_string) 717 return None; 718 return Value.uval; 719} 720 721Optional<uint64_t> DWARFFormValue::getAsReferenceUVal() const { 722 if (!isFormClass(FC_Reference)) 723 return None; 724 return Value.uval; 725} 726