aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/libs/llvm12/tools/llvm-cfi-verify/lib/FileAnalysis.cpp
blob: 100f5d876513a58e40a02b06e3968f76070416db (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
//===- FileAnalysis.cpp -----------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#include "FileAnalysis.h"
#include "GraphBuilder.h"

#include "llvm/BinaryFormat/ELF.h"
#include "llvm/DebugInfo/DWARF/DWARFContext.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCDisassembler/MCDisassembler.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCInstPrinter.h"
#include "llvm/MC/MCInstrAnalysis.h"
#include "llvm/MC/MCInstrDesc.h"
#include "llvm/MC/MCInstrInfo.h"
#include "llvm/MC/MCObjectFileInfo.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/MC/MCTargetOptions.h"
#include "llvm/Object/Binary.h"
#include "llvm/Object/COFF.h"
#include "llvm/Object/ELFObjectFile.h"
#include "llvm/Object/ObjectFile.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Support/TargetSelect.h"
#include "llvm/Support/raw_ostream.h"


using Instr = llvm::cfi_verify::FileAnalysis::Instr;
using LLVMSymbolizer = llvm::symbolize::LLVMSymbolizer;

namespace llvm {
namespace cfi_verify {

bool IgnoreDWARFFlag;

static cl::opt<bool, true> IgnoreDWARFArg(
    "ignore-dwarf",
    cl::desc(
        "Ignore all DWARF data. This relaxes the requirements for all "
        "statically linked libraries to have been compiled with '-g', but "
        "will result in false positives for 'CFI unprotected' instructions."),
    cl::location(IgnoreDWARFFlag), cl::init(false));

StringRef stringCFIProtectionStatus(CFIProtectionStatus Status) {
  switch (Status) {
  case CFIProtectionStatus::PROTECTED:
    return "PROTECTED";
  case CFIProtectionStatus::FAIL_NOT_INDIRECT_CF:
    return "FAIL_NOT_INDIRECT_CF";
  case CFIProtectionStatus::FAIL_ORPHANS:
    return "FAIL_ORPHANS";
  case CFIProtectionStatus::FAIL_BAD_CONDITIONAL_BRANCH:
    return "FAIL_BAD_CONDITIONAL_BRANCH";
  case CFIProtectionStatus::FAIL_REGISTER_CLOBBERED:
    return "FAIL_REGISTER_CLOBBERED";
  case CFIProtectionStatus::FAIL_INVALID_INSTRUCTION:
    return "FAIL_INVALID_INSTRUCTION";
  }
  llvm_unreachable("Attempted to stringify an unknown enum value.");
}

Expected<FileAnalysis> FileAnalysis::Create(StringRef Filename) {
  // Open the filename provided.
  Expected<object::OwningBinary<object::Binary>> BinaryOrErr =
      object::createBinary(Filename);
  if (!BinaryOrErr)
    return BinaryOrErr.takeError();

  // Construct the object and allow it to take ownership of the binary.
  object::OwningBinary<object::Binary> Binary = std::move(BinaryOrErr.get());
  FileAnalysis Analysis(std::move(Binary));

  Analysis.Object = dyn_cast<object::ObjectFile>(Analysis.Binary.getBinary());
  if (!Analysis.Object)
    return make_error<UnsupportedDisassembly>("Failed to cast object");

  switch (Analysis.Object->getArch()) {
    case Triple::x86:
    case Triple::x86_64:
    case Triple::aarch64:
    case Triple::aarch64_be:
      break;
    default:
      return make_error<UnsupportedDisassembly>("Unsupported architecture.");
  }

  Analysis.ObjectTriple = Analysis.Object->makeTriple();
  Analysis.Features = Analysis.Object->getFeatures();

  // Init the rest of the object.
  if (auto InitResponse = Analysis.initialiseDisassemblyMembers())
    return std::move(InitResponse);

  if (auto SectionParseResponse = Analysis.parseCodeSections())
    return std::move(SectionParseResponse);

  if (auto SymbolTableParseResponse = Analysis.parseSymbolTable())
    return std::move(SymbolTableParseResponse);

  return std::move(Analysis);
}

FileAnalysis::FileAnalysis(object::OwningBinary<object::Binary> Binary)
    : Binary(std::move(Binary)) {}

FileAnalysis::FileAnalysis(const Triple &ObjectTriple,
                           const SubtargetFeatures &Features)
    : ObjectTriple(ObjectTriple), Features(Features) {}

const Instr *
FileAnalysis::getPrevInstructionSequential(const Instr &InstrMeta) const {
  std::map<uint64_t, Instr>::const_iterator KV =
      Instructions.find(InstrMeta.VMAddress);
  if (KV == Instructions.end() || KV == Instructions.begin())
    return nullptr;

  if (!(--KV)->second.Valid)
    return nullptr;

  return &KV->second;
}

const Instr *
FileAnalysis::getNextInstructionSequential(const Instr &InstrMeta) const {
  std::map<uint64_t, Instr>::const_iterator KV =
      Instructions.find(InstrMeta.VMAddress);
  if (KV == Instructions.end() || ++KV == Instructions.end())
    return nullptr;

  if (!KV->second.Valid)
    return nullptr;

  return &KV->second;
}

bool FileAnalysis::usesRegisterOperand(const Instr &InstrMeta) const {
  for (const auto &Operand : InstrMeta.Instruction) {
    if (Operand.isReg())
      return true;
  }
  return false;
}

const Instr *FileAnalysis::getInstruction(uint64_t Address) const {
  const auto &InstrKV = Instructions.find(Address);
  if (InstrKV == Instructions.end())
    return nullptr;

  return &InstrKV->second;
}

const Instr &FileAnalysis::getInstructionOrDie(uint64_t Address) const {
  const auto &InstrKV = Instructions.find(Address);
  assert(InstrKV != Instructions.end() && "Address doesn't exist.");
  return InstrKV->second;
}

bool FileAnalysis::isCFITrap(const Instr &InstrMeta) const {
  const auto &InstrDesc = MII->get(InstrMeta.Instruction.getOpcode());
  return InstrDesc.isTrap() || willTrapOnCFIViolation(InstrMeta);
}

bool FileAnalysis::willTrapOnCFIViolation(const Instr &InstrMeta) const {
  const auto &InstrDesc = MII->get(InstrMeta.Instruction.getOpcode());
  if (!InstrDesc.isCall())
    return false;
  uint64_t Target;
  if (!MIA->evaluateBranch(InstrMeta.Instruction, InstrMeta.VMAddress,
                           InstrMeta.InstructionSize, Target))
    return false;
  return TrapOnFailFunctionAddresses.contains(Target);
}

bool FileAnalysis::canFallThrough(const Instr &InstrMeta) const {
  if (!InstrMeta.Valid)
    return false;

  if (isCFITrap(InstrMeta))
    return false;

  const auto &InstrDesc = MII->get(InstrMeta.Instruction.getOpcode());
  if (InstrDesc.mayAffectControlFlow(InstrMeta.Instruction, *RegisterInfo))
    return InstrDesc.isConditionalBranch();

  return true;
}

const Instr *
FileAnalysis::getDefiniteNextInstruction(const Instr &InstrMeta) const {
  if (!InstrMeta.Valid)
    return nullptr;

  if (isCFITrap(InstrMeta))
    return nullptr;

  const auto &InstrDesc = MII->get(InstrMeta.Instruction.getOpcode());
  const Instr *NextMetaPtr;
  if (InstrDesc.mayAffectControlFlow(InstrMeta.Instruction, *RegisterInfo)) {
    if (InstrDesc.isConditionalBranch())
      return nullptr;

    uint64_t Target;
    if (!MIA->evaluateBranch(InstrMeta.Instruction, InstrMeta.VMAddress,
                             InstrMeta.InstructionSize, Target))
      return nullptr;

    NextMetaPtr = getInstruction(Target);
  } else {
    NextMetaPtr =
        getInstruction(InstrMeta.VMAddress + InstrMeta.InstructionSize);
  }

  if (!NextMetaPtr || !NextMetaPtr->Valid)
    return nullptr;

  return NextMetaPtr;
}

std::set<const Instr *>
FileAnalysis::getDirectControlFlowXRefs(const Instr &InstrMeta) const {
  std::set<const Instr *> CFCrossReferences;
  const Instr *PrevInstruction = getPrevInstructionSequential(InstrMeta);

  if (PrevInstruction && canFallThrough(*PrevInstruction))
    CFCrossReferences.insert(PrevInstruction);

  const auto &TargetRefsKV = StaticBranchTargetings.find(InstrMeta.VMAddress);
  if (TargetRefsKV == StaticBranchTargetings.end())
    return CFCrossReferences;

  for (uint64_t SourceInstrAddress : TargetRefsKV->second) {
    const auto &SourceInstrKV = Instructions.find(SourceInstrAddress);
    if (SourceInstrKV == Instructions.end()) {
      errs() << "Failed to find source instruction at address "
             << format_hex(SourceInstrAddress, 2)
             << " for the cross-reference to instruction at address "
             << format_hex(InstrMeta.VMAddress, 2) << ".\n";
      continue;
    }

    CFCrossReferences.insert(&SourceInstrKV->second);
  }

  return CFCrossReferences;
}

const std::set<object::SectionedAddress> &
FileAnalysis::getIndirectInstructions() const {
  return IndirectInstructions;
}

const MCRegisterInfo *FileAnalysis::getRegisterInfo() const {
  return RegisterInfo.get();
}

const MCInstrInfo *FileAnalysis::getMCInstrInfo() const { return MII.get(); }

const MCInstrAnalysis *FileAnalysis::getMCInstrAnalysis() const {
  return MIA.get();
}

Expected<DIInliningInfo>
FileAnalysis::symbolizeInlinedCode(object::SectionedAddress Address) {
  assert(Symbolizer != nullptr && "Symbolizer is invalid.");

  return Symbolizer->symbolizeInlinedCode(std::string(Object->getFileName()),
                                          Address);
}

CFIProtectionStatus
FileAnalysis::validateCFIProtection(const GraphResult &Graph) const {
  const Instr *InstrMetaPtr = getInstruction(Graph.BaseAddress);
  if (!InstrMetaPtr)
    return CFIProtectionStatus::FAIL_INVALID_INSTRUCTION;

  const auto &InstrDesc = MII->get(InstrMetaPtr->Instruction.getOpcode());
  if (!InstrDesc.mayAffectControlFlow(InstrMetaPtr->Instruction, *RegisterInfo))
    return CFIProtectionStatus::FAIL_NOT_INDIRECT_CF;

  if (!usesRegisterOperand(*InstrMetaPtr))
    return CFIProtectionStatus::FAIL_NOT_INDIRECT_CF;

  if (!Graph.OrphanedNodes.empty())
    return CFIProtectionStatus::FAIL_ORPHANS;

  for (const auto &BranchNode : Graph.ConditionalBranchNodes) {
    if (!BranchNode.CFIProtection)
      return CFIProtectionStatus::FAIL_BAD_CONDITIONAL_BRANCH;
  }

  if (indirectCFOperandClobber(Graph) != Graph.BaseAddress)
    return CFIProtectionStatus::FAIL_REGISTER_CLOBBERED;

  return CFIProtectionStatus::PROTECTED;
}

uint64_t FileAnalysis::indirectCFOperandClobber(const GraphResult &Graph) const {
  assert(Graph.OrphanedNodes.empty() && "Orphaned nodes should be empty.");

  // Get the set of registers we must check to ensure they're not clobbered.
  const Instr &IndirectCF = getInstructionOrDie(Graph.BaseAddress);
  DenseSet<unsigned> RegisterNumbers;
  for (const auto &Operand : IndirectCF.Instruction) {
    if (Operand.isReg())
      RegisterNumbers.insert(Operand.getReg());
  }
  assert(RegisterNumbers.size() && "Zero register operands on indirect CF.");

  // Now check all branches to indirect CFs and ensure no clobbering happens.
  for (const auto &Branch : Graph.ConditionalBranchNodes) {
    uint64_t Node;
    if (Branch.IndirectCFIsOnTargetPath)
      Node = Branch.Target;
    else
      Node = Branch.Fallthrough;

    // Some architectures (e.g., AArch64) cannot load in an indirect branch, so
    // we allow them one load.
    bool canLoad = !MII->get(IndirectCF.Instruction.getOpcode()).mayLoad();

    // We walk backwards from the indirect CF.  It is the last node returned by
    // Graph.flattenAddress, so we skip it since we already handled it.
    DenseSet<unsigned> CurRegisterNumbers = RegisterNumbers;
    std::vector<uint64_t> Nodes = Graph.flattenAddress(Node);
    for (auto I = Nodes.rbegin() + 1, E = Nodes.rend(); I != E; ++I) {
      Node = *I;
      const Instr &NodeInstr = getInstructionOrDie(Node);
      const auto &InstrDesc = MII->get(NodeInstr.Instruction.getOpcode());

      for (auto RI = CurRegisterNumbers.begin(), RE = CurRegisterNumbers.end();
           RI != RE; ++RI) {
        unsigned RegNum = *RI;
        if (InstrDesc.hasDefOfPhysReg(NodeInstr.Instruction, RegNum,
                                      *RegisterInfo)) {
          if (!canLoad || !InstrDesc.mayLoad())
            return Node;
          canLoad = false;
          CurRegisterNumbers.erase(RI);
          // Add the registers this load reads to those we check for clobbers.
          for (unsigned i = InstrDesc.getNumDefs(),
                        e = InstrDesc.getNumOperands(); i != e; i++) {
            const auto Operand = NodeInstr.Instruction.getOperand(i);
            if (Operand.isReg())
              CurRegisterNumbers.insert(Operand.getReg());
          }
          break;
        }
      }
    }
  }

  return Graph.BaseAddress;
}

void FileAnalysis::printInstruction(const Instr &InstrMeta,
                                    raw_ostream &OS) const {
  Printer->printInst(&InstrMeta.Instruction, 0, "", *SubtargetInfo.get(), OS);
}

Error FileAnalysis::initialiseDisassemblyMembers() {
  std::string TripleName = ObjectTriple.getTriple();
  ArchName = "";
  MCPU = "";
  std::string ErrorString;

  Symbolizer.reset(new LLVMSymbolizer());

  ObjectTarget =
      TargetRegistry::lookupTarget(ArchName, ObjectTriple, ErrorString);
  if (!ObjectTarget)
    return make_error<UnsupportedDisassembly>(
        (Twine("Couldn't find target \"") + ObjectTriple.getTriple() +
         "\", failed with error: " + ErrorString)
            .str());

  RegisterInfo.reset(ObjectTarget->createMCRegInfo(TripleName));
  if (!RegisterInfo)
    return make_error<UnsupportedDisassembly>(
        "Failed to initialise RegisterInfo.");

  MCTargetOptions MCOptions;
  AsmInfo.reset(
      ObjectTarget->createMCAsmInfo(*RegisterInfo, TripleName, MCOptions));
  if (!AsmInfo)
    return make_error<UnsupportedDisassembly>("Failed to initialise AsmInfo.");

  SubtargetInfo.reset(ObjectTarget->createMCSubtargetInfo(
      TripleName, MCPU, Features.getString()));
  if (!SubtargetInfo)
    return make_error<UnsupportedDisassembly>(
        "Failed to initialise SubtargetInfo.");

  MII.reset(ObjectTarget->createMCInstrInfo());
  if (!MII)
    return make_error<UnsupportedDisassembly>("Failed to initialise MII.");

  Context.reset(new MCContext(AsmInfo.get(), RegisterInfo.get(), &MOFI));

  Disassembler.reset(
      ObjectTarget->createMCDisassembler(*SubtargetInfo, *Context));

  if (!Disassembler)
    return make_error<UnsupportedDisassembly>(
        "No disassembler available for target");

  MIA.reset(ObjectTarget->createMCInstrAnalysis(MII.get()));

  Printer.reset(ObjectTarget->createMCInstPrinter(
      ObjectTriple, AsmInfo->getAssemblerDialect(), *AsmInfo, *MII,
      *RegisterInfo));

  return Error::success();
}

Error FileAnalysis::parseCodeSections() {
  if (!IgnoreDWARFFlag) {
    std::unique_ptr<DWARFContext> DWARF = DWARFContext::create(*Object);
    if (!DWARF)
      return make_error<StringError>("Could not create DWARF information.",
                                     inconvertibleErrorCode());

    bool LineInfoValid = false;

    for (auto &Unit : DWARF->compile_units()) {
      const auto &LineTable = DWARF->getLineTableForUnit(Unit.get());
      if (LineTable && !LineTable->Rows.empty()) {
        LineInfoValid = true;
        break;
      }
    }

    if (!LineInfoValid)
      return make_error<StringError>(
          "DWARF line information missing. Did you compile with '-g'?",
          inconvertibleErrorCode());
  }

  for (const object::SectionRef &Section : Object->sections()) {
    // Ensure only executable sections get analysed.
    if (!(object::ELFSectionRef(Section).getFlags() & ELF::SHF_EXECINSTR))
      continue;

    // Avoid checking the PLT since it produces spurious failures on AArch64
    // when ignoring DWARF data.
    Expected<StringRef> NameOrErr = Section.getName();
    if (NameOrErr && *NameOrErr == ".plt")
      continue;
    consumeError(NameOrErr.takeError());

    Expected<StringRef> Contents = Section.getContents();
    if (!Contents)
      return Contents.takeError();
    ArrayRef<uint8_t> SectionBytes = arrayRefFromStringRef(*Contents);

    parseSectionContents(SectionBytes,
                         {Section.getAddress(), Section.getIndex()});
  }
  return Error::success();
}

void FileAnalysis::parseSectionContents(ArrayRef<uint8_t> SectionBytes,
                                        object::SectionedAddress Address) {
  assert(Symbolizer && "Symbolizer is uninitialised.");
  MCInst Instruction;
  Instr InstrMeta;
  uint64_t InstructionSize;

  for (uint64_t Byte = 0; Byte < SectionBytes.size();) {
    bool ValidInstruction =
        Disassembler->getInstruction(Instruction, InstructionSize,
                                     SectionBytes.drop_front(Byte), 0,
                                     outs()) == MCDisassembler::Success;

    Byte += InstructionSize;

    uint64_t VMAddress = Address.Address + Byte - InstructionSize;
    InstrMeta.Instruction = Instruction;
    InstrMeta.VMAddress = VMAddress;
    InstrMeta.InstructionSize = InstructionSize;
    InstrMeta.Valid = ValidInstruction;

    addInstruction(InstrMeta);

    if (!ValidInstruction)
      continue;

    // Skip additional parsing for instructions that do not affect the control
    // flow.
    const auto &InstrDesc = MII->get(Instruction.getOpcode());
    if (!InstrDesc.mayAffectControlFlow(Instruction, *RegisterInfo))
      continue;

    uint64_t Target;
    if (MIA->evaluateBranch(Instruction, VMAddress, InstructionSize, Target)) {
      // If the target can be evaluated, it's not indirect.
      StaticBranchTargetings[Target].push_back(VMAddress);
      continue;
    }

    if (!usesRegisterOperand(InstrMeta))
      continue;

    if (InstrDesc.isReturn())
      continue;

    // Check if this instruction exists in the range of the DWARF metadata.
    if (!IgnoreDWARFFlag) {
      auto LineInfo =
          Symbolizer->symbolizeCode(std::string(Object->getFileName()),
                                    {VMAddress, Address.SectionIndex});
      if (!LineInfo) {
        handleAllErrors(LineInfo.takeError(), [](const ErrorInfoBase &E) {
          errs() << "Symbolizer failed to get line: " << E.message() << "\n";
        });
        continue;
      }

      if (LineInfo->FileName == DILineInfo::BadString)
        continue;
    }

    IndirectInstructions.insert({VMAddress, Address.SectionIndex});
  }
}

void FileAnalysis::addInstruction(const Instr &Instruction) {
  const auto &KV =
      Instructions.insert(std::make_pair(Instruction.VMAddress, Instruction));
  if (!KV.second) {
    errs() << "Failed to add instruction at address "
           << format_hex(Instruction.VMAddress, 2)
           << ": Instruction at this address already exists.\n";
    exit(EXIT_FAILURE);
  }
}

Error FileAnalysis::parseSymbolTable() {
  // Functions that will trap on CFI violations.
  SmallSet<StringRef, 4> TrapOnFailFunctions;
  TrapOnFailFunctions.insert("__cfi_slowpath");
  TrapOnFailFunctions.insert("__cfi_slowpath_diag");
  TrapOnFailFunctions.insert("abort");

  // Look through the list of symbols for functions that will trap on CFI
  // violations.
  for (auto &Sym : Object->symbols()) {
    auto SymNameOrErr = Sym.getName();
    if (!SymNameOrErr)
      consumeError(SymNameOrErr.takeError());
    else if (TrapOnFailFunctions.contains(*SymNameOrErr)) {
      auto AddrOrErr = Sym.getAddress();
      if (!AddrOrErr)
        consumeError(AddrOrErr.takeError());
      else
        TrapOnFailFunctionAddresses.insert(*AddrOrErr);
    }
  }
  if (auto *ElfObject = dyn_cast<object::ELFObjectFileBase>(Object)) {
    for (const auto &Addr : ElfObject->getPltAddresses()) {
      if (!Addr.first)
        continue;
      object::SymbolRef Sym(*Addr.first, Object);
      auto SymNameOrErr = Sym.getName();
      if (!SymNameOrErr)
        consumeError(SymNameOrErr.takeError());
      else if (TrapOnFailFunctions.contains(*SymNameOrErr))
        TrapOnFailFunctionAddresses.insert(Addr.second);
    }
  }
  return Error::success();
}

UnsupportedDisassembly::UnsupportedDisassembly(StringRef Text)
    : Text(std::string(Text)) {}

char UnsupportedDisassembly::ID;
void UnsupportedDisassembly::log(raw_ostream &OS) const {
  OS << "Could not initialise disassembler: " << Text;
}

std::error_code UnsupportedDisassembly::convertToErrorCode() const {
  return std::error_code();
}

} // namespace cfi_verify
} // namespace llvm