1//===- DWARFDebugFrame.h - Parsing of .debug_frame ------------------------===//
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/DWARFDebugFrame.h"
10#include "llvm/ADT/DenseMap.h"
11#include "llvm/ADT/StringExtras.h"
12#include "llvm/ADT/StringRef.h"
13#include "llvm/BinaryFormat/Dwarf.h"
14#include "llvm/DebugInfo/DIContext.h"
15#include "llvm/DebugInfo/DWARF/DWARFDataExtractor.h"
16#include "llvm/Support/Compiler.h"
17#include "llvm/Support/DataExtractor.h"
18#include "llvm/Support/Errc.h"
19#include "llvm/Support/ErrorHandling.h"
20#include "llvm/Support/Format.h"
21#include "llvm/Support/raw_ostream.h"
22#include <algorithm>
23#include <cassert>
24#include <cinttypes>
25#include <cstdint>
26#include <optional>
27
28using namespace llvm;
29using namespace dwarf;
30
31static void printRegister(raw_ostream &OS, DIDumpOptions DumpOpts,
32                          unsigned RegNum) {
33  if (DumpOpts.GetNameForDWARFReg) {
34    auto RegName = DumpOpts.GetNameForDWARFReg(RegNum, DumpOpts.IsEH);
35    if (!RegName.empty()) {
36      OS << RegName;
37      return;
38    }
39  }
40  OS << "reg" << RegNum;
41}
42
43UnwindLocation UnwindLocation::createUnspecified() { return {Unspecified}; }
44
45UnwindLocation UnwindLocation::createUndefined() { return {Undefined}; }
46
47UnwindLocation UnwindLocation::createSame() { return {Same}; }
48
49UnwindLocation UnwindLocation::createIsConstant(int32_t Value) {
50  return {Constant, InvalidRegisterNumber, Value, std::nullopt, false};
51}
52
53UnwindLocation UnwindLocation::createIsCFAPlusOffset(int32_t Offset) {
54  return {CFAPlusOffset, InvalidRegisterNumber, Offset, std::nullopt, false};
55}
56
57UnwindLocation UnwindLocation::createAtCFAPlusOffset(int32_t Offset) {
58  return {CFAPlusOffset, InvalidRegisterNumber, Offset, std::nullopt, true};
59}
60
61UnwindLocation
62UnwindLocation::createIsRegisterPlusOffset(uint32_t RegNum, int32_t Offset,
63                                           std::optional<uint32_t> AddrSpace) {
64  return {RegPlusOffset, RegNum, Offset, AddrSpace, false};
65}
66
67UnwindLocation
68UnwindLocation::createAtRegisterPlusOffset(uint32_t RegNum, int32_t Offset,
69                                           std::optional<uint32_t> AddrSpace) {
70  return {RegPlusOffset, RegNum, Offset, AddrSpace, true};
71}
72
73UnwindLocation UnwindLocation::createIsDWARFExpression(DWARFExpression Expr) {
74  return {Expr, false};
75}
76
77UnwindLocation UnwindLocation::createAtDWARFExpression(DWARFExpression Expr) {
78  return {Expr, true};
79}
80
81void UnwindLocation::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const {
82  if (Dereference)
83    OS << '[';
84  switch (Kind) {
85  case Unspecified:
86    OS << "unspecified";
87    break;
88  case Undefined:
89    OS << "undefined";
90    break;
91  case Same:
92    OS << "same";
93    break;
94  case CFAPlusOffset:
95    OS << "CFA";
96    if (Offset == 0)
97      break;
98    if (Offset > 0)
99      OS << "+";
100    OS << Offset;
101    break;
102  case RegPlusOffset:
103    printRegister(OS, DumpOpts, RegNum);
104    if (Offset == 0 && !AddrSpace)
105      break;
106    if (Offset >= 0)
107      OS << "+";
108    OS << Offset;
109    if (AddrSpace)
110      OS << " in addrspace" << *AddrSpace;
111    break;
112  case DWARFExpr: {
113    Expr->print(OS, DumpOpts, nullptr);
114    break;
115  }
116  case Constant:
117    OS << Offset;
118    break;
119  }
120  if (Dereference)
121    OS << ']';
122}
123
124raw_ostream &llvm::dwarf::operator<<(raw_ostream &OS,
125                                     const UnwindLocation &UL) {
126  auto DumpOpts = DIDumpOptions();
127  UL.dump(OS, DumpOpts);
128  return OS;
129}
130
131bool UnwindLocation::operator==(const UnwindLocation &RHS) const {
132  if (Kind != RHS.Kind)
133    return false;
134  switch (Kind) {
135  case Unspecified:
136  case Undefined:
137  case Same:
138    return true;
139  case CFAPlusOffset:
140    return Offset == RHS.Offset && Dereference == RHS.Dereference;
141  case RegPlusOffset:
142    return RegNum == RHS.RegNum && Offset == RHS.Offset &&
143           Dereference == RHS.Dereference;
144  case DWARFExpr:
145    return *Expr == *RHS.Expr && Dereference == RHS.Dereference;
146  case Constant:
147    return Offset == RHS.Offset;
148  }
149  return false;
150}
151
152void RegisterLocations::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const {
153  bool First = true;
154  for (const auto &RegLocPair : Locations) {
155    if (First)
156      First = false;
157    else
158      OS << ", ";
159    printRegister(OS, DumpOpts, RegLocPair.first);
160    OS << '=';
161    RegLocPair.second.dump(OS, DumpOpts);
162  }
163}
164
165raw_ostream &llvm::dwarf::operator<<(raw_ostream &OS,
166                                     const RegisterLocations &RL) {
167  auto DumpOpts = DIDumpOptions();
168  RL.dump(OS, DumpOpts);
169  return OS;
170}
171
172void UnwindRow::dump(raw_ostream &OS, DIDumpOptions DumpOpts,
173                     unsigned IndentLevel) const {
174  OS.indent(2 * IndentLevel);
175  if (hasAddress())
176    OS << format("0x%" PRIx64 ": ", *Address);
177  OS << "CFA=";
178  CFAValue.dump(OS, DumpOpts);
179  if (RegLocs.hasLocations()) {
180    OS << ": ";
181    RegLocs.dump(OS, DumpOpts);
182  }
183  OS << "\n";
184}
185
186raw_ostream &llvm::dwarf::operator<<(raw_ostream &OS, const UnwindRow &Row) {
187  auto DumpOpts = DIDumpOptions();
188  Row.dump(OS, DumpOpts, 0);
189  return OS;
190}
191
192void UnwindTable::dump(raw_ostream &OS, DIDumpOptions DumpOpts,
193                       unsigned IndentLevel) const {
194  for (const UnwindRow &Row : Rows)
195    Row.dump(OS, DumpOpts, IndentLevel);
196}
197
198raw_ostream &llvm::dwarf::operator<<(raw_ostream &OS, const UnwindTable &Rows) {
199  auto DumpOpts = DIDumpOptions();
200  Rows.dump(OS, DumpOpts, 0);
201  return OS;
202}
203
204Expected<UnwindTable> UnwindTable::create(const FDE *Fde) {
205  const CIE *Cie = Fde->getLinkedCIE();
206  if (Cie == nullptr)
207    return createStringError(errc::invalid_argument,
208                             "unable to get CIE for FDE at offset 0x%" PRIx64,
209                             Fde->getOffset());
210
211  // Rows will be empty if there are no CFI instructions.
212  if (Cie->cfis().empty() && Fde->cfis().empty())
213    return UnwindTable();
214
215  UnwindTable UT;
216  UnwindRow Row;
217  Row.setAddress(Fde->getInitialLocation());
218  UT.EndAddress = Fde->getInitialLocation() + Fde->getAddressRange();
219  if (Error CieError = UT.parseRows(Cie->cfis(), Row, nullptr))
220    return std::move(CieError);
221  // We need to save the initial locations of registers from the CIE parsing
222  // in case we run into DW_CFA_restore or DW_CFA_restore_extended opcodes.
223  const RegisterLocations InitialLocs = Row.getRegisterLocations();
224  if (Error FdeError = UT.parseRows(Fde->cfis(), Row, &InitialLocs))
225    return std::move(FdeError);
226  // May be all the CFI instructions were DW_CFA_nop amd Row becomes empty.
227  // Do not add that to the unwind table.
228  if (Row.getRegisterLocations().hasLocations() ||
229      Row.getCFAValue().getLocation() != UnwindLocation::Unspecified)
230    UT.Rows.push_back(Row);
231  return UT;
232}
233
234Expected<UnwindTable> UnwindTable::create(const CIE *Cie) {
235  // Rows will be empty if there are no CFI instructions.
236  if (Cie->cfis().empty())
237    return UnwindTable();
238
239  UnwindTable UT;
240  UnwindRow Row;
241  if (Error CieError = UT.parseRows(Cie->cfis(), Row, nullptr))
242    return std::move(CieError);
243  // May be all the CFI instructions were DW_CFA_nop amd Row becomes empty.
244  // Do not add that to the unwind table.
245  if (Row.getRegisterLocations().hasLocations() ||
246      Row.getCFAValue().getLocation() != UnwindLocation::Unspecified)
247    UT.Rows.push_back(Row);
248  return UT;
249}
250
251// See DWARF standard v3, section 7.23
252const uint8_t DWARF_CFI_PRIMARY_OPCODE_MASK = 0xc0;
253const uint8_t DWARF_CFI_PRIMARY_OPERAND_MASK = 0x3f;
254
255Error CFIProgram::parse(DWARFDataExtractor Data, uint64_t *Offset,
256                        uint64_t EndOffset) {
257  DataExtractor::Cursor C(*Offset);
258  while (C && C.tell() < EndOffset) {
259    uint8_t Opcode = Data.getRelocatedValue(C, 1);
260    if (!C)
261      break;
262
263    // Some instructions have a primary opcode encoded in the top bits.
264    if (uint8_t Primary = Opcode & DWARF_CFI_PRIMARY_OPCODE_MASK) {
265      // If it's a primary opcode, the first operand is encoded in the bottom
266      // bits of the opcode itself.
267      uint64_t Op1 = Opcode & DWARF_CFI_PRIMARY_OPERAND_MASK;
268      switch (Primary) {
269      case DW_CFA_advance_loc:
270      case DW_CFA_restore:
271        addInstruction(Primary, Op1);
272        break;
273      case DW_CFA_offset:
274        addInstruction(Primary, Op1, Data.getULEB128(C));
275        break;
276      default:
277        llvm_unreachable("invalid primary CFI opcode");
278      }
279      continue;
280    }
281
282    // Extended opcode - its value is Opcode itself.
283    switch (Opcode) {
284    default:
285      return createStringError(errc::illegal_byte_sequence,
286                               "invalid extended CFI opcode 0x%" PRIx8, Opcode);
287    case DW_CFA_nop:
288    case DW_CFA_remember_state:
289    case DW_CFA_restore_state:
290    case DW_CFA_GNU_window_save:
291      // No operands
292      addInstruction(Opcode);
293      break;
294    case DW_CFA_set_loc:
295      // Operands: Address
296      addInstruction(Opcode, Data.getRelocatedAddress(C));
297      break;
298    case DW_CFA_advance_loc1:
299      // Operands: 1-byte delta
300      addInstruction(Opcode, Data.getRelocatedValue(C, 1));
301      break;
302    case DW_CFA_advance_loc2:
303      // Operands: 2-byte delta
304      addInstruction(Opcode, Data.getRelocatedValue(C, 2));
305      break;
306    case DW_CFA_advance_loc4:
307      // Operands: 4-byte delta
308      addInstruction(Opcode, Data.getRelocatedValue(C, 4));
309      break;
310    case DW_CFA_restore_extended:
311    case DW_CFA_undefined:
312    case DW_CFA_same_value:
313    case DW_CFA_def_cfa_register:
314    case DW_CFA_def_cfa_offset:
315    case DW_CFA_GNU_args_size:
316      // Operands: ULEB128
317      addInstruction(Opcode, Data.getULEB128(C));
318      break;
319    case DW_CFA_def_cfa_offset_sf:
320      // Operands: SLEB128
321      addInstruction(Opcode, Data.getSLEB128(C));
322      break;
323    case DW_CFA_LLVM_def_aspace_cfa:
324    case DW_CFA_LLVM_def_aspace_cfa_sf: {
325      auto RegNum = Data.getULEB128(C);
326      auto CfaOffset = Opcode == DW_CFA_LLVM_def_aspace_cfa
327                           ? Data.getULEB128(C)
328                           : Data.getSLEB128(C);
329      auto AddressSpace = Data.getULEB128(C);
330      addInstruction(Opcode, RegNum, CfaOffset, AddressSpace);
331      break;
332    }
333    case DW_CFA_offset_extended:
334    case DW_CFA_register:
335    case DW_CFA_def_cfa:
336    case DW_CFA_val_offset: {
337      // Operands: ULEB128, ULEB128
338      // Note: We can not embed getULEB128 directly into function
339      // argument list. getULEB128 changes Offset and order of evaluation
340      // for arguments is unspecified.
341      uint64_t op1 = Data.getULEB128(C);
342      uint64_t op2 = Data.getULEB128(C);
343      addInstruction(Opcode, op1, op2);
344      break;
345    }
346    case DW_CFA_offset_extended_sf:
347    case DW_CFA_def_cfa_sf:
348    case DW_CFA_val_offset_sf: {
349      // Operands: ULEB128, SLEB128
350      // Note: see comment for the previous case
351      uint64_t op1 = Data.getULEB128(C);
352      uint64_t op2 = (uint64_t)Data.getSLEB128(C);
353      addInstruction(Opcode, op1, op2);
354      break;
355    }
356    case DW_CFA_def_cfa_expression: {
357      uint64_t ExprLength = Data.getULEB128(C);
358      addInstruction(Opcode, 0);
359      StringRef Expression = Data.getBytes(C, ExprLength);
360
361      DataExtractor Extractor(Expression, Data.isLittleEndian(),
362                              Data.getAddressSize());
363      // Note. We do not pass the DWARF format to DWARFExpression, because
364      // DW_OP_call_ref, the only operation which depends on the format, is
365      // prohibited in call frame instructions, see sec. 6.4.2 in DWARFv5.
366      Instructions.back().Expression =
367          DWARFExpression(Extractor, Data.getAddressSize());
368      break;
369    }
370    case DW_CFA_expression:
371    case DW_CFA_val_expression: {
372      uint64_t RegNum = Data.getULEB128(C);
373      addInstruction(Opcode, RegNum, 0);
374
375      uint64_t BlockLength = Data.getULEB128(C);
376      StringRef Expression = Data.getBytes(C, BlockLength);
377      DataExtractor Extractor(Expression, Data.isLittleEndian(),
378                              Data.getAddressSize());
379      // Note. We do not pass the DWARF format to DWARFExpression, because
380      // DW_OP_call_ref, the only operation which depends on the format, is
381      // prohibited in call frame instructions, see sec. 6.4.2 in DWARFv5.
382      Instructions.back().Expression =
383          DWARFExpression(Extractor, Data.getAddressSize());
384      break;
385    }
386    }
387  }
388
389  *Offset = C.tell();
390  return C.takeError();
391}
392
393StringRef CFIProgram::callFrameString(unsigned Opcode) const {
394  return dwarf::CallFrameString(Opcode, Arch);
395}
396
397const char *CFIProgram::operandTypeString(CFIProgram::OperandType OT) {
398#define ENUM_TO_CSTR(e)                                                        \
399  case e:                                                                      \
400    return #e;
401  switch (OT) {
402    ENUM_TO_CSTR(OT_Unset);
403    ENUM_TO_CSTR(OT_None);
404    ENUM_TO_CSTR(OT_Address);
405    ENUM_TO_CSTR(OT_Offset);
406    ENUM_TO_CSTR(OT_FactoredCodeOffset);
407    ENUM_TO_CSTR(OT_SignedFactDataOffset);
408    ENUM_TO_CSTR(OT_UnsignedFactDataOffset);
409    ENUM_TO_CSTR(OT_Register);
410    ENUM_TO_CSTR(OT_AddressSpace);
411    ENUM_TO_CSTR(OT_Expression);
412  }
413  return "<unknown CFIProgram::OperandType>";
414}
415
416llvm::Expected<uint64_t>
417CFIProgram::Instruction::getOperandAsUnsigned(const CFIProgram &CFIP,
418                                              uint32_t OperandIdx) const {
419  if (OperandIdx >= MaxOperands)
420    return createStringError(errc::invalid_argument,
421                             "operand index %" PRIu32 " is not valid",
422                             OperandIdx);
423  OperandType Type = CFIP.getOperandTypes()[Opcode][OperandIdx];
424  uint64_t Operand = Ops[OperandIdx];
425  switch (Type) {
426  case OT_Unset:
427  case OT_None:
428  case OT_Expression:
429    return createStringError(errc::invalid_argument,
430                             "op[%" PRIu32 "] has type %s which has no value",
431                             OperandIdx, CFIProgram::operandTypeString(Type));
432
433  case OT_Offset:
434  case OT_SignedFactDataOffset:
435  case OT_UnsignedFactDataOffset:
436    return createStringError(
437        errc::invalid_argument,
438        "op[%" PRIu32 "] has OperandType OT_Offset which produces a signed "
439        "result, call getOperandAsSigned instead",
440        OperandIdx);
441
442  case OT_Address:
443  case OT_Register:
444  case OT_AddressSpace:
445    return Operand;
446
447  case OT_FactoredCodeOffset: {
448    const uint64_t CodeAlignmentFactor = CFIP.codeAlign();
449    if (CodeAlignmentFactor == 0)
450      return createStringError(
451          errc::invalid_argument,
452          "op[%" PRIu32 "] has type OT_FactoredCodeOffset but code alignment "
453          "is zero",
454          OperandIdx);
455    return Operand * CodeAlignmentFactor;
456  }
457  }
458  llvm_unreachable("invalid operand type");
459}
460
461llvm::Expected<int64_t>
462CFIProgram::Instruction::getOperandAsSigned(const CFIProgram &CFIP,
463                                            uint32_t OperandIdx) const {
464  if (OperandIdx >= MaxOperands)
465    return createStringError(errc::invalid_argument,
466                             "operand index %" PRIu32 " is not valid",
467                             OperandIdx);
468  OperandType Type = CFIP.getOperandTypes()[Opcode][OperandIdx];
469  uint64_t Operand = Ops[OperandIdx];
470  switch (Type) {
471  case OT_Unset:
472  case OT_None:
473  case OT_Expression:
474    return createStringError(errc::invalid_argument,
475                             "op[%" PRIu32 "] has type %s which has no value",
476                             OperandIdx, CFIProgram::operandTypeString(Type));
477
478  case OT_Address:
479  case OT_Register:
480  case OT_AddressSpace:
481    return createStringError(
482        errc::invalid_argument,
483        "op[%" PRIu32 "] has OperandType %s which produces an unsigned result, "
484        "call getOperandAsUnsigned instead",
485        OperandIdx, CFIProgram::operandTypeString(Type));
486
487  case OT_Offset:
488    return (int64_t)Operand;
489
490  case OT_FactoredCodeOffset:
491  case OT_SignedFactDataOffset: {
492    const int64_t DataAlignmentFactor = CFIP.dataAlign();
493    if (DataAlignmentFactor == 0)
494      return createStringError(errc::invalid_argument,
495                               "op[%" PRIu32 "] has type %s but data "
496                               "alignment is zero",
497                               OperandIdx, CFIProgram::operandTypeString(Type));
498    return int64_t(Operand) * DataAlignmentFactor;
499  }
500
501  case OT_UnsignedFactDataOffset: {
502    const int64_t DataAlignmentFactor = CFIP.dataAlign();
503    if (DataAlignmentFactor == 0)
504      return createStringError(errc::invalid_argument,
505                               "op[%" PRIu32
506                               "] has type OT_UnsignedFactDataOffset but data "
507                               "alignment is zero",
508                               OperandIdx);
509    return Operand * DataAlignmentFactor;
510  }
511  }
512  llvm_unreachable("invalid operand type");
513}
514
515Error UnwindTable::parseRows(const CFIProgram &CFIP, UnwindRow &Row,
516                             const RegisterLocations *InitialLocs) {
517  // State consists of CFA value and register locations.
518  std::vector<std::pair<UnwindLocation, RegisterLocations>> States;
519  for (const CFIProgram::Instruction &Inst : CFIP) {
520    switch (Inst.Opcode) {
521    case dwarf::DW_CFA_set_loc: {
522      // The DW_CFA_set_loc instruction takes a single operand that
523      // represents a target address. The required action is to create a new
524      // table row using the specified address as the location. All other
525      // values in the new row are initially identical to the current row.
526      // The new location value is always greater than the current one. If
527      // the segment_size field of this FDE's CIE is non- zero, the initial
528      // location is preceded by a segment selector of the given length
529      llvm::Expected<uint64_t> NewAddress = Inst.getOperandAsUnsigned(CFIP, 0);
530      if (!NewAddress)
531        return NewAddress.takeError();
532      if (*NewAddress <= Row.getAddress())
533        return createStringError(
534            errc::invalid_argument,
535            "%s with adrress 0x%" PRIx64 " which must be greater than the "
536            "current row address 0x%" PRIx64,
537            CFIP.callFrameString(Inst.Opcode).str().c_str(), *NewAddress,
538            Row.getAddress());
539      Rows.push_back(Row);
540      Row.setAddress(*NewAddress);
541      break;
542    }
543
544    case dwarf::DW_CFA_advance_loc:
545    case dwarf::DW_CFA_advance_loc1:
546    case dwarf::DW_CFA_advance_loc2:
547    case dwarf::DW_CFA_advance_loc4: {
548      // The DW_CFA_advance instruction takes a single operand that
549      // represents a constant delta. The required action is to create a new
550      // table row with a location value that is computed by taking the
551      // current entry���s location value and adding the value of delta *
552      // code_alignment_factor. All other values in the new row are initially
553      // identical to the current row.
554      Rows.push_back(Row);
555      llvm::Expected<uint64_t> Offset = Inst.getOperandAsUnsigned(CFIP, 0);
556      if (!Offset)
557        return Offset.takeError();
558      Row.slideAddress(*Offset);
559      break;
560    }
561
562    case dwarf::DW_CFA_restore:
563    case dwarf::DW_CFA_restore_extended: {
564      // The DW_CFA_restore instruction takes a single operand (encoded with
565      // the opcode) that represents a register number. The required action
566      // is to change the rule for the indicated register to the rule
567      // assigned it by the initial_instructions in the CIE.
568      if (InitialLocs == nullptr)
569        return createStringError(
570            errc::invalid_argument, "%s encountered while parsing a CIE",
571            CFIP.callFrameString(Inst.Opcode).str().c_str());
572      llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0);
573      if (!RegNum)
574        return RegNum.takeError();
575      if (std::optional<UnwindLocation> O =
576              InitialLocs->getRegisterLocation(*RegNum))
577        Row.getRegisterLocations().setRegisterLocation(*RegNum, *O);
578      else
579        Row.getRegisterLocations().removeRegisterLocation(*RegNum);
580      break;
581    }
582
583    case dwarf::DW_CFA_offset:
584    case dwarf::DW_CFA_offset_extended:
585    case dwarf::DW_CFA_offset_extended_sf: {
586      llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0);
587      if (!RegNum)
588        return RegNum.takeError();
589      llvm::Expected<int64_t> Offset = Inst.getOperandAsSigned(CFIP, 1);
590      if (!Offset)
591        return Offset.takeError();
592      Row.getRegisterLocations().setRegisterLocation(
593          *RegNum, UnwindLocation::createAtCFAPlusOffset(*Offset));
594      break;
595    }
596
597    case dwarf::DW_CFA_nop:
598      break;
599
600    case dwarf::DW_CFA_remember_state:
601      States.push_back(
602          std::make_pair(Row.getCFAValue(), Row.getRegisterLocations()));
603      break;
604
605    case dwarf::DW_CFA_restore_state:
606      if (States.empty())
607        return createStringError(errc::invalid_argument,
608                                 "DW_CFA_restore_state without a matching "
609                                 "previous DW_CFA_remember_state");
610      Row.getCFAValue() = States.back().first;
611      Row.getRegisterLocations() = States.back().second;
612      States.pop_back();
613      break;
614
615    case dwarf::DW_CFA_GNU_window_save:
616      switch (CFIP.triple()) {
617      case Triple::aarch64:
618      case Triple::aarch64_be:
619      case Triple::aarch64_32: {
620        // DW_CFA_GNU_window_save is used for different things on different
621        // architectures. For aarch64 it is known as
622        // DW_CFA_AARCH64_negate_ra_state. The action is to toggle the
623        // value of the return address state between 1 and 0. If there is
624        // no rule for the AARCH64_DWARF_PAUTH_RA_STATE register, then it
625        // should be initially set to 1.
626        constexpr uint32_t AArch64DWARFPAuthRaState = 34;
627        auto LRLoc = Row.getRegisterLocations().getRegisterLocation(
628            AArch64DWARFPAuthRaState);
629        if (LRLoc) {
630          if (LRLoc->getLocation() == UnwindLocation::Constant) {
631            // Toggle the constant value from 0 to 1 or 1 to 0.
632            LRLoc->setConstant(LRLoc->getConstant() ^ 1);
633          } else {
634            return createStringError(
635                errc::invalid_argument,
636                "%s encountered when existing rule for this register is not "
637                "a constant",
638                CFIP.callFrameString(Inst.Opcode).str().c_str());
639          }
640        } else {
641          Row.getRegisterLocations().setRegisterLocation(
642              AArch64DWARFPAuthRaState, UnwindLocation::createIsConstant(1));
643        }
644        break;
645      }
646
647      case Triple::sparc:
648      case Triple::sparcv9:
649      case Triple::sparcel:
650        for (uint32_t RegNum = 16; RegNum < 32; ++RegNum) {
651          Row.getRegisterLocations().setRegisterLocation(
652              RegNum, UnwindLocation::createAtCFAPlusOffset((RegNum - 16) * 8));
653        }
654        break;
655
656      default: {
657        return createStringError(
658            errc::not_supported,
659            "DW_CFA opcode %#x is not supported for architecture %s",
660            Inst.Opcode, Triple::getArchTypeName(CFIP.triple()).str().c_str());
661
662        break;
663      }
664      }
665      break;
666
667    case dwarf::DW_CFA_undefined: {
668      llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0);
669      if (!RegNum)
670        return RegNum.takeError();
671      Row.getRegisterLocations().setRegisterLocation(
672          *RegNum, UnwindLocation::createUndefined());
673      break;
674    }
675
676    case dwarf::DW_CFA_same_value: {
677      llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0);
678      if (!RegNum)
679        return RegNum.takeError();
680      Row.getRegisterLocations().setRegisterLocation(
681          *RegNum, UnwindLocation::createSame());
682      break;
683    }
684
685    case dwarf::DW_CFA_GNU_args_size:
686      break;
687
688    case dwarf::DW_CFA_register: {
689      llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0);
690      if (!RegNum)
691        return RegNum.takeError();
692      llvm::Expected<uint64_t> NewRegNum = Inst.getOperandAsUnsigned(CFIP, 1);
693      if (!NewRegNum)
694        return NewRegNum.takeError();
695      Row.getRegisterLocations().setRegisterLocation(
696          *RegNum, UnwindLocation::createIsRegisterPlusOffset(*NewRegNum, 0));
697      break;
698    }
699
700    case dwarf::DW_CFA_val_offset:
701    case dwarf::DW_CFA_val_offset_sf: {
702      llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0);
703      if (!RegNum)
704        return RegNum.takeError();
705      llvm::Expected<int64_t> Offset = Inst.getOperandAsSigned(CFIP, 1);
706      if (!Offset)
707        return Offset.takeError();
708      Row.getRegisterLocations().setRegisterLocation(
709          *RegNum, UnwindLocation::createIsCFAPlusOffset(*Offset));
710      break;
711    }
712
713    case dwarf::DW_CFA_expression: {
714      llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0);
715      if (!RegNum)
716        return RegNum.takeError();
717      Row.getRegisterLocations().setRegisterLocation(
718          *RegNum, UnwindLocation::createAtDWARFExpression(*Inst.Expression));
719      break;
720    }
721
722    case dwarf::DW_CFA_val_expression: {
723      llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0);
724      if (!RegNum)
725        return RegNum.takeError();
726      Row.getRegisterLocations().setRegisterLocation(
727          *RegNum, UnwindLocation::createIsDWARFExpression(*Inst.Expression));
728      break;
729    }
730
731    case dwarf::DW_CFA_def_cfa_register: {
732      llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0);
733      if (!RegNum)
734        return RegNum.takeError();
735      if (Row.getCFAValue().getLocation() != UnwindLocation::RegPlusOffset)
736        Row.getCFAValue() =
737            UnwindLocation::createIsRegisterPlusOffset(*RegNum, 0);
738      else
739        Row.getCFAValue().setRegister(*RegNum);
740      break;
741    }
742
743    case dwarf::DW_CFA_def_cfa_offset:
744    case dwarf::DW_CFA_def_cfa_offset_sf: {
745      llvm::Expected<int64_t> Offset = Inst.getOperandAsSigned(CFIP, 0);
746      if (!Offset)
747        return Offset.takeError();
748      if (Row.getCFAValue().getLocation() != UnwindLocation::RegPlusOffset) {
749        return createStringError(
750            errc::invalid_argument,
751            "%s found when CFA rule was not RegPlusOffset",
752            CFIP.callFrameString(Inst.Opcode).str().c_str());
753      }
754      Row.getCFAValue().setOffset(*Offset);
755      break;
756    }
757
758    case dwarf::DW_CFA_def_cfa:
759    case dwarf::DW_CFA_def_cfa_sf: {
760      llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0);
761      if (!RegNum)
762        return RegNum.takeError();
763      llvm::Expected<int64_t> Offset = Inst.getOperandAsSigned(CFIP, 1);
764      if (!Offset)
765        return Offset.takeError();
766      Row.getCFAValue() =
767          UnwindLocation::createIsRegisterPlusOffset(*RegNum, *Offset);
768      break;
769    }
770
771    case dwarf::DW_CFA_LLVM_def_aspace_cfa:
772    case dwarf::DW_CFA_LLVM_def_aspace_cfa_sf: {
773      llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0);
774      if (!RegNum)
775        return RegNum.takeError();
776      llvm::Expected<int64_t> Offset = Inst.getOperandAsSigned(CFIP, 1);
777      if (!Offset)
778        return Offset.takeError();
779      llvm::Expected<uint32_t> CFAAddrSpace =
780          Inst.getOperandAsUnsigned(CFIP, 2);
781      if (!CFAAddrSpace)
782        return CFAAddrSpace.takeError();
783      Row.getCFAValue() = UnwindLocation::createIsRegisterPlusOffset(
784          *RegNum, *Offset, *CFAAddrSpace);
785      break;
786    }
787
788    case dwarf::DW_CFA_def_cfa_expression:
789      Row.getCFAValue() =
790          UnwindLocation::createIsDWARFExpression(*Inst.Expression);
791      break;
792    }
793  }
794  return Error::success();
795}
796
797ArrayRef<CFIProgram::OperandType[CFIProgram::MaxOperands]>
798CFIProgram::getOperandTypes() {
799  static OperandType OpTypes[DW_CFA_restore + 1][MaxOperands];
800  static bool Initialized = false;
801  if (Initialized) {
802    return ArrayRef<OperandType[MaxOperands]>(&OpTypes[0], DW_CFA_restore + 1);
803  }
804  Initialized = true;
805
806#define DECLARE_OP3(OP, OPTYPE0, OPTYPE1, OPTYPE2)                             \
807  do {                                                                         \
808    OpTypes[OP][0] = OPTYPE0;                                                  \
809    OpTypes[OP][1] = OPTYPE1;                                                  \
810    OpTypes[OP][2] = OPTYPE2;                                                  \
811  } while (false)
812#define DECLARE_OP2(OP, OPTYPE0, OPTYPE1)                                      \
813  DECLARE_OP3(OP, OPTYPE0, OPTYPE1, OT_None)
814#define DECLARE_OP1(OP, OPTYPE0) DECLARE_OP2(OP, OPTYPE0, OT_None)
815#define DECLARE_OP0(OP) DECLARE_OP1(OP, OT_None)
816
817  DECLARE_OP1(DW_CFA_set_loc, OT_Address);
818  DECLARE_OP1(DW_CFA_advance_loc, OT_FactoredCodeOffset);
819  DECLARE_OP1(DW_CFA_advance_loc1, OT_FactoredCodeOffset);
820  DECLARE_OP1(DW_CFA_advance_loc2, OT_FactoredCodeOffset);
821  DECLARE_OP1(DW_CFA_advance_loc4, OT_FactoredCodeOffset);
822  DECLARE_OP1(DW_CFA_MIPS_advance_loc8, OT_FactoredCodeOffset);
823  DECLARE_OP2(DW_CFA_def_cfa, OT_Register, OT_Offset);
824  DECLARE_OP2(DW_CFA_def_cfa_sf, OT_Register, OT_SignedFactDataOffset);
825  DECLARE_OP1(DW_CFA_def_cfa_register, OT_Register);
826  DECLARE_OP3(DW_CFA_LLVM_def_aspace_cfa, OT_Register, OT_Offset,
827              OT_AddressSpace);
828  DECLARE_OP3(DW_CFA_LLVM_def_aspace_cfa_sf, OT_Register,
829              OT_SignedFactDataOffset, OT_AddressSpace);
830  DECLARE_OP1(DW_CFA_def_cfa_offset, OT_Offset);
831  DECLARE_OP1(DW_CFA_def_cfa_offset_sf, OT_SignedFactDataOffset);
832  DECLARE_OP1(DW_CFA_def_cfa_expression, OT_Expression);
833  DECLARE_OP1(DW_CFA_undefined, OT_Register);
834  DECLARE_OP1(DW_CFA_same_value, OT_Register);
835  DECLARE_OP2(DW_CFA_offset, OT_Register, OT_UnsignedFactDataOffset);
836  DECLARE_OP2(DW_CFA_offset_extended, OT_Register, OT_UnsignedFactDataOffset);
837  DECLARE_OP2(DW_CFA_offset_extended_sf, OT_Register, OT_SignedFactDataOffset);
838  DECLARE_OP2(DW_CFA_val_offset, OT_Register, OT_UnsignedFactDataOffset);
839  DECLARE_OP2(DW_CFA_val_offset_sf, OT_Register, OT_SignedFactDataOffset);
840  DECLARE_OP2(DW_CFA_register, OT_Register, OT_Register);
841  DECLARE_OP2(DW_CFA_expression, OT_Register, OT_Expression);
842  DECLARE_OP2(DW_CFA_val_expression, OT_Register, OT_Expression);
843  DECLARE_OP1(DW_CFA_restore, OT_Register);
844  DECLARE_OP1(DW_CFA_restore_extended, OT_Register);
845  DECLARE_OP0(DW_CFA_remember_state);
846  DECLARE_OP0(DW_CFA_restore_state);
847  DECLARE_OP0(DW_CFA_GNU_window_save);
848  DECLARE_OP1(DW_CFA_GNU_args_size, OT_Offset);
849  DECLARE_OP0(DW_CFA_nop);
850
851#undef DECLARE_OP0
852#undef DECLARE_OP1
853#undef DECLARE_OP2
854
855  return ArrayRef<OperandType[MaxOperands]>(&OpTypes[0], DW_CFA_restore + 1);
856}
857
858/// Print \p Opcode's operand number \p OperandIdx which has value \p Operand.
859void CFIProgram::printOperand(raw_ostream &OS, DIDumpOptions DumpOpts,
860                              const Instruction &Instr, unsigned OperandIdx,
861                              uint64_t Operand) const {
862  assert(OperandIdx < MaxOperands);
863  uint8_t Opcode = Instr.Opcode;
864  OperandType Type = getOperandTypes()[Opcode][OperandIdx];
865
866  switch (Type) {
867  case OT_Unset: {
868    OS << " Unsupported " << (OperandIdx ? "second" : "first") << " operand to";
869    auto OpcodeName = callFrameString(Opcode);
870    if (!OpcodeName.empty())
871      OS << " " << OpcodeName;
872    else
873      OS << format(" Opcode %x",  Opcode);
874    break;
875  }
876  case OT_None:
877    break;
878  case OT_Address:
879    OS << format(" %" PRIx64, Operand);
880    break;
881  case OT_Offset:
882    // The offsets are all encoded in a unsigned form, but in practice
883    // consumers use them signed. It's most certainly legacy due to
884    // the lack of signed variants in the first Dwarf standards.
885    OS << format(" %+" PRId64, int64_t(Operand));
886    break;
887  case OT_FactoredCodeOffset: // Always Unsigned
888    if (CodeAlignmentFactor)
889      OS << format(" %" PRId64, Operand * CodeAlignmentFactor);
890    else
891      OS << format(" %" PRId64 "*code_alignment_factor" , Operand);
892    break;
893  case OT_SignedFactDataOffset:
894    if (DataAlignmentFactor)
895      OS << format(" %" PRId64, int64_t(Operand) * DataAlignmentFactor);
896    else
897      OS << format(" %" PRId64 "*data_alignment_factor" , int64_t(Operand));
898    break;
899  case OT_UnsignedFactDataOffset:
900    if (DataAlignmentFactor)
901      OS << format(" %" PRId64, Operand * DataAlignmentFactor);
902    else
903      OS << format(" %" PRId64 "*data_alignment_factor" , Operand);
904    break;
905  case OT_Register:
906    OS << ' ';
907    printRegister(OS, DumpOpts, Operand);
908    break;
909  case OT_AddressSpace:
910    OS << format(" in addrspace%" PRId64, Operand);
911    break;
912  case OT_Expression:
913    assert(Instr.Expression && "missing DWARFExpression object");
914    OS << " ";
915    Instr.Expression->print(OS, DumpOpts, nullptr);
916    break;
917  }
918}
919
920void CFIProgram::dump(raw_ostream &OS, DIDumpOptions DumpOpts,
921                      unsigned IndentLevel) const {
922  for (const auto &Instr : Instructions) {
923    uint8_t Opcode = Instr.Opcode;
924    OS.indent(2 * IndentLevel);
925    OS << callFrameString(Opcode) << ":";
926    for (unsigned i = 0; i < Instr.Ops.size(); ++i)
927      printOperand(OS, DumpOpts, Instr, i, Instr.Ops[i]);
928    OS << '\n';
929  }
930}
931
932// Returns the CIE identifier to be used by the requested format.
933// CIE ids for .debug_frame sections are defined in Section 7.24 of DWARFv5.
934// For CIE ID in .eh_frame sections see
935// https://refspecs.linuxfoundation.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/ehframechpt.html
936constexpr uint64_t getCIEId(bool IsDWARF64, bool IsEH) {
937  if (IsEH)
938    return 0;
939  if (IsDWARF64)
940    return DW64_CIE_ID;
941  return DW_CIE_ID;
942}
943
944void CIE::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const {
945  // A CIE with a zero length is a terminator entry in the .eh_frame section.
946  if (DumpOpts.IsEH && Length == 0) {
947    OS << format("%08" PRIx64, Offset) << " ZERO terminator\n";
948    return;
949  }
950
951  OS << format("%08" PRIx64, Offset)
952     << format(" %0*" PRIx64, IsDWARF64 ? 16 : 8, Length)
953     << format(" %0*" PRIx64, IsDWARF64 && !DumpOpts.IsEH ? 16 : 8,
954               getCIEId(IsDWARF64, DumpOpts.IsEH))
955     << " CIE\n"
956     << "  Format:                " << FormatString(IsDWARF64) << "\n";
957  if (DumpOpts.IsEH && Version != 1)
958    OS << "WARNING: unsupported CIE version\n";
959  OS << format("  Version:               %d\n", Version)
960     << "  Augmentation:          \"" << Augmentation << "\"\n";
961  if (Version >= 4) {
962    OS << format("  Address size:          %u\n", (uint32_t)AddressSize);
963    OS << format("  Segment desc size:     %u\n",
964                 (uint32_t)SegmentDescriptorSize);
965  }
966  OS << format("  Code alignment factor: %u\n", (uint32_t)CodeAlignmentFactor);
967  OS << format("  Data alignment factor: %d\n", (int32_t)DataAlignmentFactor);
968  OS << format("  Return address column: %d\n", (int32_t)ReturnAddressRegister);
969  if (Personality)
970    OS << format("  Personality Address: %016" PRIx64 "\n", *Personality);
971  if (!AugmentationData.empty()) {
972    OS << "  Augmentation data:    ";
973    for (uint8_t Byte : AugmentationData)
974      OS << ' ' << hexdigit(Byte >> 4) << hexdigit(Byte & 0xf);
975    OS << "\n";
976  }
977  OS << "\n";
978  CFIs.dump(OS, DumpOpts);
979  OS << "\n";
980
981  if (Expected<UnwindTable> RowsOrErr = UnwindTable::create(this))
982    RowsOrErr->dump(OS, DumpOpts, 1);
983  else {
984    DumpOpts.RecoverableErrorHandler(joinErrors(
985        createStringError(errc::invalid_argument,
986                          "decoding the CIE opcodes into rows failed"),
987        RowsOrErr.takeError()));
988  }
989  OS << "\n";
990}
991
992void FDE::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const {
993  OS << format("%08" PRIx64, Offset)
994     << format(" %0*" PRIx64, IsDWARF64 ? 16 : 8, Length)
995     << format(" %0*" PRIx64, IsDWARF64 && !DumpOpts.IsEH ? 16 : 8, CIEPointer)
996     << " FDE cie=";
997  if (LinkedCIE)
998    OS << format("%08" PRIx64, LinkedCIE->getOffset());
999  else
1000    OS << "<invalid offset>";
1001  OS << format(" pc=%08" PRIx64 "...%08" PRIx64 "\n", InitialLocation,
1002               InitialLocation + AddressRange);
1003  OS << "  Format:       " << FormatString(IsDWARF64) << "\n";
1004  if (LSDAAddress)
1005    OS << format("  LSDA Address: %016" PRIx64 "\n", *LSDAAddress);
1006  CFIs.dump(OS, DumpOpts);
1007  OS << "\n";
1008
1009  if (Expected<UnwindTable> RowsOrErr = UnwindTable::create(this))
1010    RowsOrErr->dump(OS, DumpOpts, 1);
1011  else {
1012    DumpOpts.RecoverableErrorHandler(joinErrors(
1013        createStringError(errc::invalid_argument,
1014                          "decoding the FDE opcodes into rows failed"),
1015        RowsOrErr.takeError()));
1016  }
1017  OS << "\n";
1018}
1019
1020DWARFDebugFrame::DWARFDebugFrame(Triple::ArchType Arch,
1021    bool IsEH, uint64_t EHFrameAddress)
1022    : Arch(Arch), IsEH(IsEH), EHFrameAddress(EHFrameAddress) {}
1023
1024DWARFDebugFrame::~DWARFDebugFrame() = default;
1025
1026static void LLVM_ATTRIBUTE_UNUSED dumpDataAux(DataExtractor Data,
1027                                              uint64_t Offset, int Length) {
1028  errs() << "DUMP: ";
1029  for (int i = 0; i < Length; ++i) {
1030    uint8_t c = Data.getU8(&Offset);
1031    errs().write_hex(c); errs() << " ";
1032  }
1033  errs() << "\n";
1034}
1035
1036Error DWARFDebugFrame::parse(DWARFDataExtractor Data) {
1037  uint64_t Offset = 0;
1038  DenseMap<uint64_t, CIE *> CIEs;
1039
1040  while (Data.isValidOffset(Offset)) {
1041    uint64_t StartOffset = Offset;
1042
1043    uint64_t Length;
1044    DwarfFormat Format;
1045    std::tie(Length, Format) = Data.getInitialLength(&Offset);
1046    bool IsDWARF64 = Format == DWARF64;
1047
1048    // If the Length is 0, then this CIE is a terminator. We add it because some
1049    // dumper tools might need it to print something special for such entries
1050    // (e.g. llvm-objdump --dwarf=frames prints "ZERO terminator").
1051    if (Length == 0) {
1052      auto Cie = std::make_unique<CIE>(
1053          IsDWARF64, StartOffset, 0, 0, SmallString<8>(), 0, 0, 0, 0, 0,
1054          SmallString<8>(), 0, 0, std::nullopt, std::nullopt, Arch);
1055      CIEs[StartOffset] = Cie.get();
1056      Entries.push_back(std::move(Cie));
1057      break;
1058    }
1059
1060    // At this point, Offset points to the next field after Length.
1061    // Length is the structure size excluding itself. Compute an offset one
1062    // past the end of the structure (needed to know how many instructions to
1063    // read).
1064    uint64_t StartStructureOffset = Offset;
1065    uint64_t EndStructureOffset = Offset + Length;
1066
1067    // The Id field's size depends on the DWARF format
1068    Error Err = Error::success();
1069    uint64_t Id = Data.getRelocatedValue((IsDWARF64 && !IsEH) ? 8 : 4, &Offset,
1070                                         /*SectionIndex=*/nullptr, &Err);
1071    if (Err)
1072      return Err;
1073
1074    if (Id == getCIEId(IsDWARF64, IsEH)) {
1075      uint8_t Version = Data.getU8(&Offset);
1076      const char *Augmentation = Data.getCStr(&Offset);
1077      StringRef AugmentationString(Augmentation ? Augmentation : "");
1078      uint8_t AddressSize = Version < 4 ? Data.getAddressSize() :
1079                                          Data.getU8(&Offset);
1080      Data.setAddressSize(AddressSize);
1081      uint8_t SegmentDescriptorSize = Version < 4 ? 0 : Data.getU8(&Offset);
1082      uint64_t CodeAlignmentFactor = Data.getULEB128(&Offset);
1083      int64_t DataAlignmentFactor = Data.getSLEB128(&Offset);
1084      uint64_t ReturnAddressRegister =
1085          Version == 1 ? Data.getU8(&Offset) : Data.getULEB128(&Offset);
1086
1087      // Parse the augmentation data for EH CIEs
1088      StringRef AugmentationData("");
1089      uint32_t FDEPointerEncoding = DW_EH_PE_absptr;
1090      uint32_t LSDAPointerEncoding = DW_EH_PE_omit;
1091      std::optional<uint64_t> Personality;
1092      std::optional<uint32_t> PersonalityEncoding;
1093      if (IsEH) {
1094        std::optional<uint64_t> AugmentationLength;
1095        uint64_t StartAugmentationOffset;
1096        uint64_t EndAugmentationOffset;
1097
1098        // Walk the augmentation string to get all the augmentation data.
1099        for (unsigned i = 0, e = AugmentationString.size(); i != e; ++i) {
1100          switch (AugmentationString[i]) {
1101          default:
1102            return createStringError(
1103                errc::invalid_argument,
1104                "unknown augmentation character %c in entry at 0x%" PRIx64,
1105                AugmentationString[i], StartOffset);
1106          case 'L':
1107            LSDAPointerEncoding = Data.getU8(&Offset);
1108            break;
1109          case 'P': {
1110            if (Personality)
1111              return createStringError(
1112                  errc::invalid_argument,
1113                  "duplicate personality in entry at 0x%" PRIx64, StartOffset);
1114            PersonalityEncoding = Data.getU8(&Offset);
1115            Personality = Data.getEncodedPointer(
1116                &Offset, *PersonalityEncoding,
1117                EHFrameAddress ? EHFrameAddress + Offset : 0);
1118            break;
1119          }
1120          case 'R':
1121            FDEPointerEncoding = Data.getU8(&Offset);
1122            break;
1123          case 'S':
1124            // Current frame is a signal trampoline.
1125            break;
1126          case 'z':
1127            if (i)
1128              return createStringError(
1129                  errc::invalid_argument,
1130                  "'z' must be the first character at 0x%" PRIx64, StartOffset);
1131            // Parse the augmentation length first.  We only parse it if
1132            // the string contains a 'z'.
1133            AugmentationLength = Data.getULEB128(&Offset);
1134            StartAugmentationOffset = Offset;
1135            EndAugmentationOffset = Offset + *AugmentationLength;
1136            break;
1137          case 'B':
1138            // B-Key is used for signing functions associated with this
1139            // augmentation string
1140            break;
1141            // This stack frame contains MTE tagged data, so needs to be
1142            // untagged on unwind.
1143          case 'G':
1144            break;
1145          }
1146        }
1147
1148        if (AugmentationLength) {
1149          if (Offset != EndAugmentationOffset)
1150            return createStringError(errc::invalid_argument,
1151                                     "parsing augmentation data at 0x%" PRIx64
1152                                     " failed",
1153                                     StartOffset);
1154          AugmentationData = Data.getData().slice(StartAugmentationOffset,
1155                                                  EndAugmentationOffset);
1156        }
1157      }
1158
1159      auto Cie = std::make_unique<CIE>(
1160          IsDWARF64, StartOffset, Length, Version, AugmentationString,
1161          AddressSize, SegmentDescriptorSize, CodeAlignmentFactor,
1162          DataAlignmentFactor, ReturnAddressRegister, AugmentationData,
1163          FDEPointerEncoding, LSDAPointerEncoding, Personality,
1164          PersonalityEncoding, Arch);
1165      CIEs[StartOffset] = Cie.get();
1166      Entries.emplace_back(std::move(Cie));
1167    } else {
1168      // FDE
1169      uint64_t CIEPointer = Id;
1170      uint64_t InitialLocation = 0;
1171      uint64_t AddressRange = 0;
1172      std::optional<uint64_t> LSDAAddress;
1173      CIE *Cie = CIEs[IsEH ? (StartStructureOffset - CIEPointer) : CIEPointer];
1174
1175      if (IsEH) {
1176        // The address size is encoded in the CIE we reference.
1177        if (!Cie)
1178          return createStringError(errc::invalid_argument,
1179                                   "parsing FDE data at 0x%" PRIx64
1180                                   " failed due to missing CIE",
1181                                   StartOffset);
1182        if (auto Val =
1183                Data.getEncodedPointer(&Offset, Cie->getFDEPointerEncoding(),
1184                                       EHFrameAddress + Offset)) {
1185          InitialLocation = *Val;
1186        }
1187        if (auto Val = Data.getEncodedPointer(
1188                &Offset, Cie->getFDEPointerEncoding(), 0)) {
1189          AddressRange = *Val;
1190        }
1191
1192        StringRef AugmentationString = Cie->getAugmentationString();
1193        if (!AugmentationString.empty()) {
1194          // Parse the augmentation length and data for this FDE.
1195          uint64_t AugmentationLength = Data.getULEB128(&Offset);
1196
1197          uint64_t EndAugmentationOffset = Offset + AugmentationLength;
1198
1199          // Decode the LSDA if the CIE augmentation string said we should.
1200          if (Cie->getLSDAPointerEncoding() != DW_EH_PE_omit) {
1201            LSDAAddress = Data.getEncodedPointer(
1202                &Offset, Cie->getLSDAPointerEncoding(),
1203                EHFrameAddress ? Offset + EHFrameAddress : 0);
1204          }
1205
1206          if (Offset != EndAugmentationOffset)
1207            return createStringError(errc::invalid_argument,
1208                                     "parsing augmentation data at 0x%" PRIx64
1209                                     " failed",
1210                                     StartOffset);
1211        }
1212      } else {
1213        InitialLocation = Data.getRelocatedAddress(&Offset);
1214        AddressRange = Data.getRelocatedAddress(&Offset);
1215      }
1216
1217      Entries.emplace_back(new FDE(IsDWARF64, StartOffset, Length, CIEPointer,
1218                                   InitialLocation, AddressRange, Cie,
1219                                   LSDAAddress, Arch));
1220    }
1221
1222    if (Error E =
1223            Entries.back()->cfis().parse(Data, &Offset, EndStructureOffset))
1224      return E;
1225
1226    if (Offset != EndStructureOffset)
1227      return createStringError(
1228          errc::invalid_argument,
1229          "parsing entry instructions at 0x%" PRIx64 " failed", StartOffset);
1230  }
1231
1232  return Error::success();
1233}
1234
1235FrameEntry *DWARFDebugFrame::getEntryAtOffset(uint64_t Offset) const {
1236  auto It = partition_point(Entries, [=](const std::unique_ptr<FrameEntry> &E) {
1237    return E->getOffset() < Offset;
1238  });
1239  if (It != Entries.end() && (*It)->getOffset() == Offset)
1240    return It->get();
1241  return nullptr;
1242}
1243
1244void DWARFDebugFrame::dump(raw_ostream &OS, DIDumpOptions DumpOpts,
1245                           std::optional<uint64_t> Offset) const {
1246  DumpOpts.IsEH = IsEH;
1247  if (Offset) {
1248    if (auto *Entry = getEntryAtOffset(*Offset))
1249      Entry->dump(OS, DumpOpts);
1250    return;
1251  }
1252
1253  OS << "\n";
1254  for (const auto &Entry : Entries)
1255    Entry->dump(OS, DumpOpts);
1256}
1257