| //===- DWARFDebugFrame.h - Parsing of .debug_frame ------------------------===// |
| // |
| // 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 "llvm/DebugInfo/DWARF/DWARFDebugFrame.h" |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/ADT/StringExtras.h" |
| #include "llvm/ADT/StringRef.h" |
| #include "llvm/BinaryFormat/Dwarf.h" |
| #include "llvm/DebugInfo/DIContext.h" |
| #include "llvm/DebugInfo/DWARF/DWARFCFIPrinter.h" |
| #include "llvm/DebugInfo/DWARF/DWARFCFIProgram.h" |
| #include "llvm/DebugInfo/DWARF/DWARFDataExtractor.h" |
| #include "llvm/DebugInfo/DWARF/DWARFExpression.h" |
| #include "llvm/Support/Compiler.h" |
| #include "llvm/Support/DataExtractor.h" |
| #include "llvm/Support/Errc.h" |
| #include "llvm/Support/Error.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/Format.h" |
| #include "llvm/Support/raw_ostream.h" |
| #include <cassert> |
| #include <cinttypes> |
| #include <cstdint> |
| #include <optional> |
| |
| using namespace llvm; |
| using namespace dwarf; |
| |
| static void printRegister(raw_ostream &OS, DIDumpOptions DumpOpts, |
| unsigned RegNum) { |
| if (DumpOpts.GetNameForDWARFReg) { |
| auto RegName = DumpOpts.GetNameForDWARFReg(RegNum, DumpOpts.IsEH); |
| if (!RegName.empty()) { |
| OS << RegName; |
| return; |
| } |
| } |
| OS << "reg" << RegNum; |
| } |
| |
| UnwindLocation UnwindLocation::createUnspecified() { return {Unspecified}; } |
| |
| UnwindLocation UnwindLocation::createUndefined() { return {Undefined}; } |
| |
| UnwindLocation UnwindLocation::createSame() { return {Same}; } |
| |
| UnwindLocation UnwindLocation::createIsConstant(int32_t Value) { |
| return {Constant, InvalidRegisterNumber, Value, std::nullopt, false}; |
| } |
| |
| UnwindLocation UnwindLocation::createIsCFAPlusOffset(int32_t Offset) { |
| return {CFAPlusOffset, InvalidRegisterNumber, Offset, std::nullopt, false}; |
| } |
| |
| UnwindLocation UnwindLocation::createAtCFAPlusOffset(int32_t Offset) { |
| return {CFAPlusOffset, InvalidRegisterNumber, Offset, std::nullopt, true}; |
| } |
| |
| UnwindLocation |
| UnwindLocation::createIsRegisterPlusOffset(uint32_t RegNum, int32_t Offset, |
| std::optional<uint32_t> AddrSpace) { |
| return {RegPlusOffset, RegNum, Offset, AddrSpace, false}; |
| } |
| |
| UnwindLocation |
| UnwindLocation::createAtRegisterPlusOffset(uint32_t RegNum, int32_t Offset, |
| std::optional<uint32_t> AddrSpace) { |
| return {RegPlusOffset, RegNum, Offset, AddrSpace, true}; |
| } |
| |
| UnwindLocation UnwindLocation::createIsDWARFExpression(DWARFExpression Expr) { |
| return {Expr, false}; |
| } |
| |
| UnwindLocation UnwindLocation::createAtDWARFExpression(DWARFExpression Expr) { |
| return {Expr, true}; |
| } |
| |
| void UnwindLocation::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const { |
| if (Dereference) |
| OS << '['; |
| switch (Kind) { |
| case Unspecified: |
| OS << "unspecified"; |
| break; |
| case Undefined: |
| OS << "undefined"; |
| break; |
| case Same: |
| OS << "same"; |
| break; |
| case CFAPlusOffset: |
| OS << "CFA"; |
| if (Offset == 0) |
| break; |
| if (Offset > 0) |
| OS << "+"; |
| OS << Offset; |
| break; |
| case RegPlusOffset: |
| printRegister(OS, DumpOpts, RegNum); |
| if (Offset == 0 && !AddrSpace) |
| break; |
| if (Offset >= 0) |
| OS << "+"; |
| OS << Offset; |
| if (AddrSpace) |
| OS << " in addrspace" << *AddrSpace; |
| break; |
| case DWARFExpr: { |
| if (Expr) |
| DWARFExpressionPrinter::print(&(*Expr), OS, DumpOpts, nullptr); |
| break; |
| } |
| case Constant: |
| OS << Offset; |
| break; |
| } |
| if (Dereference) |
| OS << ']'; |
| } |
| |
| raw_ostream &llvm::dwarf::operator<<(raw_ostream &OS, |
| const UnwindLocation &UL) { |
| auto DumpOpts = DIDumpOptions(); |
| UL.dump(OS, DumpOpts); |
| return OS; |
| } |
| |
| bool UnwindLocation::operator==(const UnwindLocation &RHS) const { |
| if (Kind != RHS.Kind) |
| return false; |
| switch (Kind) { |
| case Unspecified: |
| case Undefined: |
| case Same: |
| return true; |
| case CFAPlusOffset: |
| return Offset == RHS.Offset && Dereference == RHS.Dereference; |
| case RegPlusOffset: |
| return RegNum == RHS.RegNum && Offset == RHS.Offset && |
| Dereference == RHS.Dereference; |
| case DWARFExpr: |
| return *Expr == *RHS.Expr && Dereference == RHS.Dereference; |
| case Constant: |
| return Offset == RHS.Offset; |
| } |
| return false; |
| } |
| |
| void RegisterLocations::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const { |
| bool First = true; |
| for (const auto &RegLocPair : Locations) { |
| if (First) |
| First = false; |
| else |
| OS << ", "; |
| printRegister(OS, DumpOpts, RegLocPair.first); |
| OS << '='; |
| RegLocPair.second.dump(OS, DumpOpts); |
| } |
| } |
| |
| raw_ostream &llvm::dwarf::operator<<(raw_ostream &OS, |
| const RegisterLocations &RL) { |
| auto DumpOpts = DIDumpOptions(); |
| RL.dump(OS, DumpOpts); |
| return OS; |
| } |
| |
| void UnwindRow::dump(raw_ostream &OS, DIDumpOptions DumpOpts, |
| unsigned IndentLevel) const { |
| OS.indent(2 * IndentLevel); |
| if (hasAddress()) |
| OS << format("0x%" PRIx64 ": ", *Address); |
| OS << "CFA="; |
| CFAValue.dump(OS, DumpOpts); |
| if (RegLocs.hasLocations()) { |
| OS << ": "; |
| RegLocs.dump(OS, DumpOpts); |
| } |
| OS << "\n"; |
| } |
| |
| raw_ostream &llvm::dwarf::operator<<(raw_ostream &OS, const UnwindRow &Row) { |
| auto DumpOpts = DIDumpOptions(); |
| Row.dump(OS, DumpOpts, 0); |
| return OS; |
| } |
| |
| void UnwindTable::dump(raw_ostream &OS, DIDumpOptions DumpOpts, |
| unsigned IndentLevel) const { |
| for (const UnwindRow &Row : Rows) |
| Row.dump(OS, DumpOpts, IndentLevel); |
| } |
| |
| raw_ostream &llvm::dwarf::operator<<(raw_ostream &OS, const UnwindTable &Rows) { |
| auto DumpOpts = DIDumpOptions(); |
| Rows.dump(OS, DumpOpts, 0); |
| return OS; |
| } |
| |
| Expected<UnwindTable> llvm::dwarf::createUnwindTable(const FDE *Fde) { |
| const CIE *Cie = Fde->getLinkedCIE(); |
| if (Cie == nullptr) |
| return createStringError(errc::invalid_argument, |
| "unable to get CIE for FDE at offset 0x%" PRIx64, |
| Fde->getOffset()); |
| |
| // Rows will be empty if there are no CFI instructions. |
| if (Cie->cfis().empty() && Fde->cfis().empty()) |
| return UnwindTable({}); |
| |
| UnwindTable::RowContainer CieRows; |
| UnwindRow Row; |
| Row.setAddress(Fde->getInitialLocation()); |
| if (Error CieError = parseRows(Cie->cfis(), Row, nullptr).moveInto(CieRows)) |
| return std::move(CieError); |
| // We need to save the initial locations of registers from the CIE parsing |
| // in case we run into DW_CFA_restore or DW_CFA_restore_extended opcodes. |
| UnwindTable::RowContainer FdeRows; |
| const RegisterLocations InitialLocs = Row.getRegisterLocations(); |
| if (Error FdeError = |
| parseRows(Fde->cfis(), Row, &InitialLocs).moveInto(FdeRows)) |
| return std::move(FdeError); |
| |
| UnwindTable::RowContainer AllRows; |
| AllRows.insert(AllRows.end(), CieRows.begin(), CieRows.end()); |
| AllRows.insert(AllRows.end(), FdeRows.begin(), FdeRows.end()); |
| |
| // May be all the CFI instructions were DW_CFA_nop amd Row becomes empty. |
| // Do not add that to the unwind table. |
| if (Row.getRegisterLocations().hasLocations() || |
| Row.getCFAValue().getLocation() != UnwindLocation::Unspecified) |
| AllRows.push_back(Row); |
| return UnwindTable(std::move(AllRows)); |
| } |
| |
| Expected<UnwindTable> llvm::dwarf::createUnwindTable(const CIE *Cie) { |
| // Rows will be empty if there are no CFI instructions. |
| if (Cie->cfis().empty()) |
| return UnwindTable({}); |
| |
| UnwindTable::RowContainer Rows; |
| UnwindRow Row; |
| if (Error CieError = parseRows(Cie->cfis(), Row, nullptr).moveInto(Rows)) |
| return std::move(CieError); |
| // May be all the CFI instructions were DW_CFA_nop amd Row becomes empty. |
| // Do not add that to the unwind table. |
| if (Row.getRegisterLocations().hasLocations() || |
| Row.getCFAValue().getLocation() != UnwindLocation::Unspecified) |
| Rows.push_back(Row); |
| return UnwindTable(std::move(Rows)); |
| } |
| |
| Expected<UnwindTable::RowContainer> |
| llvm::dwarf::parseRows(const CFIProgram &CFIP, UnwindRow &Row, |
| const RegisterLocations *InitialLocs) { |
| // All the unwinding rows parsed during processing of the CFI program. |
| UnwindTable::RowContainer Rows; |
| |
| // State consists of CFA value and register locations. |
| std::vector<std::pair<UnwindLocation, RegisterLocations>> States; |
| for (const CFIProgram::Instruction &Inst : CFIP) { |
| switch (Inst.Opcode) { |
| case dwarf::DW_CFA_set_loc: { |
| // The DW_CFA_set_loc instruction takes a single operand that |
| // represents a target address. The required action is to create a new |
| // table row using the specified address as the location. All other |
| // values in the new row are initially identical to the current row. |
| // The new location value is always greater than the current one. If |
| // the segment_size field of this FDE's CIE is non- zero, the initial |
| // location is preceded by a segment selector of the given length |
| llvm::Expected<uint64_t> NewAddress = Inst.getOperandAsUnsigned(CFIP, 0); |
| if (!NewAddress) |
| return NewAddress.takeError(); |
| if (*NewAddress <= Row.getAddress()) |
| return createStringError( |
| errc::invalid_argument, |
| "%s with adrress 0x%" PRIx64 " which must be greater than the " |
| "current row address 0x%" PRIx64, |
| CFIP.callFrameString(Inst.Opcode).str().c_str(), *NewAddress, |
| Row.getAddress()); |
| Rows.push_back(Row); |
| Row.setAddress(*NewAddress); |
| break; |
| } |
| |
| case dwarf::DW_CFA_advance_loc: |
| case dwarf::DW_CFA_advance_loc1: |
| case dwarf::DW_CFA_advance_loc2: |
| case dwarf::DW_CFA_advance_loc4: { |
| // The DW_CFA_advance instruction takes a single operand that |
| // represents a constant delta. The required action is to create a new |
| // table row with a location value that is computed by taking the |
| // current entry’s location value and adding the value of delta * |
| // code_alignment_factor. All other values in the new row are initially |
| // identical to the current row. |
| Rows.push_back(Row); |
| llvm::Expected<uint64_t> Offset = Inst.getOperandAsUnsigned(CFIP, 0); |
| if (!Offset) |
| return Offset.takeError(); |
| Row.slideAddress(*Offset); |
| break; |
| } |
| |
| case dwarf::DW_CFA_restore: |
| case dwarf::DW_CFA_restore_extended: { |
| // The DW_CFA_restore instruction takes a single operand (encoded with |
| // the opcode) that represents a register number. The required action |
| // is to change the rule for the indicated register to the rule |
| // assigned it by the initial_instructions in the CIE. |
| if (InitialLocs == nullptr) |
| return createStringError( |
| errc::invalid_argument, "%s encountered while parsing a CIE", |
| CFIP.callFrameString(Inst.Opcode).str().c_str()); |
| llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0); |
| if (!RegNum) |
| return RegNum.takeError(); |
| if (std::optional<UnwindLocation> O = |
| InitialLocs->getRegisterLocation(*RegNum)) |
| Row.getRegisterLocations().setRegisterLocation(*RegNum, *O); |
| else |
| Row.getRegisterLocations().removeRegisterLocation(*RegNum); |
| break; |
| } |
| |
| case dwarf::DW_CFA_offset: |
| case dwarf::DW_CFA_offset_extended: |
| case dwarf::DW_CFA_offset_extended_sf: { |
| llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0); |
| if (!RegNum) |
| return RegNum.takeError(); |
| llvm::Expected<int64_t> Offset = Inst.getOperandAsSigned(CFIP, 1); |
| if (!Offset) |
| return Offset.takeError(); |
| Row.getRegisterLocations().setRegisterLocation( |
| *RegNum, UnwindLocation::createAtCFAPlusOffset(*Offset)); |
| break; |
| } |
| |
| case dwarf::DW_CFA_nop: |
| break; |
| |
| case dwarf::DW_CFA_remember_state: |
| States.push_back( |
| std::make_pair(Row.getCFAValue(), Row.getRegisterLocations())); |
| break; |
| |
| case dwarf::DW_CFA_restore_state: |
| if (States.empty()) |
| return createStringError(errc::invalid_argument, |
| "DW_CFA_restore_state without a matching " |
| "previous DW_CFA_remember_state"); |
| Row.getCFAValue() = States.back().first; |
| Row.getRegisterLocations() = States.back().second; |
| States.pop_back(); |
| break; |
| |
| case dwarf::DW_CFA_GNU_window_save: |
| switch (CFIP.triple()) { |
| case Triple::aarch64: |
| case Triple::aarch64_be: |
| case Triple::aarch64_32: { |
| // DW_CFA_GNU_window_save is used for different things on different |
| // architectures. For aarch64 it is known as |
| // DW_CFA_AARCH64_negate_ra_state. The action is to toggle the |
| // value of the return address state between 1 and 0. If there is |
| // no rule for the AARCH64_DWARF_PAUTH_RA_STATE register, then it |
| // should be initially set to 1. |
| constexpr uint32_t AArch64DWARFPAuthRaState = 34; |
| auto LRLoc = Row.getRegisterLocations().getRegisterLocation( |
| AArch64DWARFPAuthRaState); |
| if (LRLoc) { |
| if (LRLoc->getLocation() == UnwindLocation::Constant) { |
| // Toggle the constant value from 0 to 1 or 1 to 0. |
| LRLoc->setConstant(LRLoc->getConstant() ^ 1); |
| Row.getRegisterLocations().setRegisterLocation( |
| AArch64DWARFPAuthRaState, *LRLoc); |
| } else { |
| return createStringError( |
| errc::invalid_argument, |
| "%s encountered when existing rule for this register is not " |
| "a constant", |
| CFIP.callFrameString(Inst.Opcode).str().c_str()); |
| } |
| } else { |
| Row.getRegisterLocations().setRegisterLocation( |
| AArch64DWARFPAuthRaState, UnwindLocation::createIsConstant(1)); |
| } |
| break; |
| } |
| |
| case Triple::sparc: |
| case Triple::sparcv9: |
| case Triple::sparcel: |
| for (uint32_t RegNum = 16; RegNum < 32; ++RegNum) { |
| Row.getRegisterLocations().setRegisterLocation( |
| RegNum, UnwindLocation::createAtCFAPlusOffset((RegNum - 16) * 8)); |
| } |
| break; |
| |
| default: { |
| return createStringError( |
| errc::not_supported, |
| "DW_CFA opcode %#x is not supported for architecture %s", |
| Inst.Opcode, Triple::getArchTypeName(CFIP.triple()).str().c_str()); |
| |
| break; |
| } |
| } |
| break; |
| |
| case dwarf::DW_CFA_AARCH64_negate_ra_state_with_pc: { |
| constexpr uint32_t AArch64DWARFPAuthRaState = 34; |
| auto LRLoc = Row.getRegisterLocations().getRegisterLocation( |
| AArch64DWARFPAuthRaState); |
| if (LRLoc) { |
| if (LRLoc->getLocation() == UnwindLocation::Constant) { |
| // Toggle the constant value of bits[1:0] from 0 to 1 or 1 to 0. |
| LRLoc->setConstant(LRLoc->getConstant() ^ 0x3); |
| } else { |
| return createStringError( |
| errc::invalid_argument, |
| "%s encountered when existing rule for this register is not " |
| "a constant", |
| CFIP.callFrameString(Inst.Opcode).str().c_str()); |
| } |
| } else { |
| Row.getRegisterLocations().setRegisterLocation( |
| AArch64DWARFPAuthRaState, UnwindLocation::createIsConstant(0x3)); |
| } |
| break; |
| } |
| |
| case dwarf::DW_CFA_undefined: { |
| llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0); |
| if (!RegNum) |
| return RegNum.takeError(); |
| Row.getRegisterLocations().setRegisterLocation( |
| *RegNum, UnwindLocation::createUndefined()); |
| break; |
| } |
| |
| case dwarf::DW_CFA_same_value: { |
| llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0); |
| if (!RegNum) |
| return RegNum.takeError(); |
| Row.getRegisterLocations().setRegisterLocation( |
| *RegNum, UnwindLocation::createSame()); |
| break; |
| } |
| |
| case dwarf::DW_CFA_GNU_args_size: |
| break; |
| |
| case dwarf::DW_CFA_register: { |
| llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0); |
| if (!RegNum) |
| return RegNum.takeError(); |
| llvm::Expected<uint64_t> NewRegNum = Inst.getOperandAsUnsigned(CFIP, 1); |
| if (!NewRegNum) |
| return NewRegNum.takeError(); |
| Row.getRegisterLocations().setRegisterLocation( |
| *RegNum, UnwindLocation::createIsRegisterPlusOffset(*NewRegNum, 0)); |
| break; |
| } |
| |
| case dwarf::DW_CFA_val_offset: |
| case dwarf::DW_CFA_val_offset_sf: { |
| llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0); |
| if (!RegNum) |
| return RegNum.takeError(); |
| llvm::Expected<int64_t> Offset = Inst.getOperandAsSigned(CFIP, 1); |
| if (!Offset) |
| return Offset.takeError(); |
| Row.getRegisterLocations().setRegisterLocation( |
| *RegNum, UnwindLocation::createIsCFAPlusOffset(*Offset)); |
| break; |
| } |
| |
| case dwarf::DW_CFA_expression: { |
| llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0); |
| if (!RegNum) |
| return RegNum.takeError(); |
| Row.getRegisterLocations().setRegisterLocation( |
| *RegNum, UnwindLocation::createAtDWARFExpression(*Inst.Expression)); |
| break; |
| } |
| |
| case dwarf::DW_CFA_val_expression: { |
| llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0); |
| if (!RegNum) |
| return RegNum.takeError(); |
| Row.getRegisterLocations().setRegisterLocation( |
| *RegNum, UnwindLocation::createIsDWARFExpression(*Inst.Expression)); |
| break; |
| } |
| |
| case dwarf::DW_CFA_def_cfa_register: { |
| llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0); |
| if (!RegNum) |
| return RegNum.takeError(); |
| if (Row.getCFAValue().getLocation() != UnwindLocation::RegPlusOffset) |
| Row.getCFAValue() = |
| UnwindLocation::createIsRegisterPlusOffset(*RegNum, 0); |
| else |
| Row.getCFAValue().setRegister(*RegNum); |
| break; |
| } |
| |
| case dwarf::DW_CFA_def_cfa_offset: |
| case dwarf::DW_CFA_def_cfa_offset_sf: { |
| llvm::Expected<int64_t> Offset = Inst.getOperandAsSigned(CFIP, 0); |
| if (!Offset) |
| return Offset.takeError(); |
| if (Row.getCFAValue().getLocation() != UnwindLocation::RegPlusOffset) { |
| return createStringError( |
| errc::invalid_argument, |
| "%s found when CFA rule was not RegPlusOffset", |
| CFIP.callFrameString(Inst.Opcode).str().c_str()); |
| } |
| Row.getCFAValue().setOffset(*Offset); |
| break; |
| } |
| |
| case dwarf::DW_CFA_def_cfa: |
| case dwarf::DW_CFA_def_cfa_sf: { |
| llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0); |
| if (!RegNum) |
| return RegNum.takeError(); |
| llvm::Expected<int64_t> Offset = Inst.getOperandAsSigned(CFIP, 1); |
| if (!Offset) |
| return Offset.takeError(); |
| Row.getCFAValue() = |
| UnwindLocation::createIsRegisterPlusOffset(*RegNum, *Offset); |
| break; |
| } |
| |
| case dwarf::DW_CFA_LLVM_def_aspace_cfa: |
| case dwarf::DW_CFA_LLVM_def_aspace_cfa_sf: { |
| llvm::Expected<uint64_t> RegNum = Inst.getOperandAsUnsigned(CFIP, 0); |
| if (!RegNum) |
| return RegNum.takeError(); |
| llvm::Expected<int64_t> Offset = Inst.getOperandAsSigned(CFIP, 1); |
| if (!Offset) |
| return Offset.takeError(); |
| llvm::Expected<uint32_t> CFAAddrSpace = |
| Inst.getOperandAsUnsigned(CFIP, 2); |
| if (!CFAAddrSpace) |
| return CFAAddrSpace.takeError(); |
| Row.getCFAValue() = UnwindLocation::createIsRegisterPlusOffset( |
| *RegNum, *Offset, *CFAAddrSpace); |
| break; |
| } |
| |
| case dwarf::DW_CFA_def_cfa_expression: |
| Row.getCFAValue() = |
| UnwindLocation::createIsDWARFExpression(*Inst.Expression); |
| break; |
| } |
| } |
| return Rows; |
| } |
| |
| // Returns the CIE identifier to be used by the requested format. |
| // CIE ids for .debug_frame sections are defined in Section 7.24 of DWARFv5. |
| // For CIE ID in .eh_frame sections see |
| // https://refspecs.linuxfoundation.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/ehframechpt.html |
| constexpr uint64_t getCIEId(bool IsDWARF64, bool IsEH) { |
| if (IsEH) |
| return 0; |
| if (IsDWARF64) |
| return DW64_CIE_ID; |
| return DW_CIE_ID; |
| } |
| |
| void CIE::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const { |
| // A CIE with a zero length is a terminator entry in the .eh_frame section. |
| if (DumpOpts.IsEH && Length == 0) { |
| OS << format("%08" PRIx64, Offset) << " ZERO terminator\n"; |
| return; |
| } |
| |
| OS << format("%08" PRIx64, Offset) |
| << format(" %0*" PRIx64, IsDWARF64 ? 16 : 8, Length) |
| << format(" %0*" PRIx64, IsDWARF64 && !DumpOpts.IsEH ? 16 : 8, |
| getCIEId(IsDWARF64, DumpOpts.IsEH)) |
| << " CIE\n" |
| << " Format: " << FormatString(IsDWARF64) << "\n"; |
| if (DumpOpts.IsEH && Version != 1) |
| OS << "WARNING: unsupported CIE version\n"; |
| OS << format(" Version: %d\n", Version) |
| << " Augmentation: \"" << Augmentation << "\"\n"; |
| if (Version >= 4) { |
| OS << format(" Address size: %u\n", (uint32_t)AddressSize); |
| OS << format(" Segment desc size: %u\n", |
| (uint32_t)SegmentDescriptorSize); |
| } |
| OS << format(" Code alignment factor: %u\n", (uint32_t)CodeAlignmentFactor); |
| OS << format(" Data alignment factor: %d\n", (int32_t)DataAlignmentFactor); |
| OS << format(" Return address column: %d\n", (int32_t)ReturnAddressRegister); |
| if (Personality) |
| OS << format(" Personality Address: %016" PRIx64 "\n", *Personality); |
| if (!AugmentationData.empty()) { |
| OS << " Augmentation data: "; |
| for (uint8_t Byte : AugmentationData) |
| OS << ' ' << hexdigit(Byte >> 4) << hexdigit(Byte & 0xf); |
| OS << "\n"; |
| } |
| OS << "\n"; |
| printCFIProgram(CFIs, OS, DumpOpts, /*IndentLevel=*/1, |
| /*InitialLocation=*/{}); |
| OS << "\n"; |
| |
| if (Expected<UnwindTable> RowsOrErr = createUnwindTable(this)) |
| RowsOrErr->dump(OS, DumpOpts, 1); |
| else { |
| DumpOpts.RecoverableErrorHandler(joinErrors( |
| createStringError(errc::invalid_argument, |
| "decoding the CIE opcodes into rows failed"), |
| RowsOrErr.takeError())); |
| } |
| OS << "\n"; |
| } |
| |
| void FDE::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const { |
| OS << format("%08" PRIx64, Offset) |
| << format(" %0*" PRIx64, IsDWARF64 ? 16 : 8, Length) |
| << format(" %0*" PRIx64, IsDWARF64 && !DumpOpts.IsEH ? 16 : 8, CIEPointer) |
| << " FDE cie="; |
| if (LinkedCIE) |
| OS << format("%08" PRIx64, LinkedCIE->getOffset()); |
| else |
| OS << "<invalid offset>"; |
| OS << format(" pc=%08" PRIx64 "...%08" PRIx64 "\n", InitialLocation, |
| InitialLocation + AddressRange); |
| OS << " Format: " << FormatString(IsDWARF64) << "\n"; |
| if (LSDAAddress) |
| OS << format(" LSDA Address: %016" PRIx64 "\n", *LSDAAddress); |
| printCFIProgram(CFIs, OS, DumpOpts, /*IndentLevel=*/1, InitialLocation); |
| OS << "\n"; |
| |
| if (Expected<UnwindTable> RowsOrErr = createUnwindTable(this)) |
| RowsOrErr->dump(OS, DumpOpts, 1); |
| else { |
| DumpOpts.RecoverableErrorHandler(joinErrors( |
| createStringError(errc::invalid_argument, |
| "decoding the FDE opcodes into rows failed"), |
| RowsOrErr.takeError())); |
| } |
| OS << "\n"; |
| } |
| |
| DWARFDebugFrame::DWARFDebugFrame(Triple::ArchType Arch, |
| bool IsEH, uint64_t EHFrameAddress) |
| : Arch(Arch), IsEH(IsEH), EHFrameAddress(EHFrameAddress) {} |
| |
| DWARFDebugFrame::~DWARFDebugFrame() = default; |
| |
| static void LLVM_ATTRIBUTE_UNUSED dumpDataAux(DataExtractor Data, |
| uint64_t Offset, int Length) { |
| errs() << "DUMP: "; |
| for (int i = 0; i < Length; ++i) { |
| uint8_t c = Data.getU8(&Offset); |
| errs().write_hex(c); errs() << " "; |
| } |
| errs() << "\n"; |
| } |
| |
| Error DWARFDebugFrame::parse(DWARFDataExtractor Data) { |
| uint64_t Offset = 0; |
| DenseMap<uint64_t, CIE *> CIEs; |
| |
| while (Data.isValidOffset(Offset)) { |
| uint64_t StartOffset = Offset; |
| |
| uint64_t Length; |
| DwarfFormat Format; |
| std::tie(Length, Format) = Data.getInitialLength(&Offset); |
| bool IsDWARF64 = Format == DWARF64; |
| |
| // If the Length is 0, then this CIE is a terminator. We add it because some |
| // dumper tools might need it to print something special for such entries |
| // (e.g. llvm-objdump --dwarf=frames prints "ZERO terminator"). |
| if (Length == 0) { |
| auto Cie = std::make_unique<CIE>( |
| IsDWARF64, StartOffset, 0, 0, SmallString<8>(), 0, 0, 0, 0, 0, |
| SmallString<8>(), 0, 0, std::nullopt, std::nullopt, Arch); |
| CIEs[StartOffset] = Cie.get(); |
| Entries.push_back(std::move(Cie)); |
| break; |
| } |
| |
| // At this point, Offset points to the next field after Length. |
| // Length is the structure size excluding itself. Compute an offset one |
| // past the end of the structure (needed to know how many instructions to |
| // read). |
| uint64_t StartStructureOffset = Offset; |
| uint64_t EndStructureOffset = Offset + Length; |
| |
| // The Id field's size depends on the DWARF format |
| Error Err = Error::success(); |
| uint64_t Id = Data.getRelocatedValue((IsDWARF64 && !IsEH) ? 8 : 4, &Offset, |
| /*SectionIndex=*/nullptr, &Err); |
| if (Err) |
| return Err; |
| |
| if (Id == getCIEId(IsDWARF64, IsEH)) { |
| uint8_t Version = Data.getU8(&Offset); |
| const char *Augmentation = Data.getCStr(&Offset); |
| StringRef AugmentationString(Augmentation ? Augmentation : ""); |
| uint8_t AddressSize = Version < 4 ? Data.getAddressSize() : |
| Data.getU8(&Offset); |
| Data.setAddressSize(AddressSize); |
| uint8_t SegmentDescriptorSize = Version < 4 ? 0 : Data.getU8(&Offset); |
| uint64_t CodeAlignmentFactor = Data.getULEB128(&Offset); |
| int64_t DataAlignmentFactor = Data.getSLEB128(&Offset); |
| uint64_t ReturnAddressRegister = |
| Version == 1 ? Data.getU8(&Offset) : Data.getULEB128(&Offset); |
| |
| // Parse the augmentation data for EH CIEs |
| StringRef AugmentationData(""); |
| uint32_t FDEPointerEncoding = DW_EH_PE_absptr; |
| uint32_t LSDAPointerEncoding = DW_EH_PE_omit; |
| std::optional<uint64_t> Personality; |
| std::optional<uint32_t> PersonalityEncoding; |
| if (IsEH) { |
| std::optional<uint64_t> AugmentationLength; |
| uint64_t StartAugmentationOffset; |
| uint64_t EndAugmentationOffset; |
| |
| // Walk the augmentation string to get all the augmentation data. |
| for (unsigned i = 0, e = AugmentationString.size(); i != e; ++i) { |
| switch (AugmentationString[i]) { |
| default: |
| return createStringError( |
| errc::invalid_argument, |
| "unknown augmentation character %c in entry at 0x%" PRIx64, |
| AugmentationString[i], StartOffset); |
| case 'L': |
| LSDAPointerEncoding = Data.getU8(&Offset); |
| break; |
| case 'P': { |
| if (Personality) |
| return createStringError( |
| errc::invalid_argument, |
| "duplicate personality in entry at 0x%" PRIx64, StartOffset); |
| PersonalityEncoding = Data.getU8(&Offset); |
| Personality = Data.getEncodedPointer( |
| &Offset, *PersonalityEncoding, |
| EHFrameAddress ? EHFrameAddress + Offset : 0); |
| break; |
| } |
| case 'R': |
| FDEPointerEncoding = Data.getU8(&Offset); |
| break; |
| case 'S': |
| // Current frame is a signal trampoline. |
| break; |
| case 'z': |
| if (i) |
| return createStringError( |
| errc::invalid_argument, |
| "'z' must be the first character at 0x%" PRIx64, StartOffset); |
| // Parse the augmentation length first. We only parse it if |
| // the string contains a 'z'. |
| AugmentationLength = Data.getULEB128(&Offset); |
| StartAugmentationOffset = Offset; |
| EndAugmentationOffset = Offset + *AugmentationLength; |
| break; |
| case 'B': |
| // B-Key is used for signing functions associated with this |
| // augmentation string |
| break; |
| // This stack frame contains MTE tagged data, so needs to be |
| // untagged on unwind. |
| case 'G': |
| break; |
| } |
| } |
| |
| if (AugmentationLength) { |
| if (Offset != EndAugmentationOffset) |
| return createStringError(errc::invalid_argument, |
| "parsing augmentation data at 0x%" PRIx64 |
| " failed", |
| StartOffset); |
| AugmentationData = Data.getData().slice(StartAugmentationOffset, |
| EndAugmentationOffset); |
| } |
| } |
| |
| auto Cie = std::make_unique<CIE>( |
| IsDWARF64, StartOffset, Length, Version, AugmentationString, |
| AddressSize, SegmentDescriptorSize, CodeAlignmentFactor, |
| DataAlignmentFactor, ReturnAddressRegister, AugmentationData, |
| FDEPointerEncoding, LSDAPointerEncoding, Personality, |
| PersonalityEncoding, Arch); |
| CIEs[StartOffset] = Cie.get(); |
| Entries.emplace_back(std::move(Cie)); |
| } else { |
| // FDE |
| uint64_t CIEPointer = Id; |
| uint64_t InitialLocation = 0; |
| uint64_t AddressRange = 0; |
| std::optional<uint64_t> LSDAAddress; |
| CIE *Cie = CIEs[IsEH ? (StartStructureOffset - CIEPointer) : CIEPointer]; |
| |
| if (IsEH) { |
| // The address size is encoded in the CIE we reference. |
| if (!Cie) |
| return createStringError(errc::invalid_argument, |
| "parsing FDE data at 0x%" PRIx64 |
| " failed due to missing CIE", |
| StartOffset); |
| if (auto Val = |
| Data.getEncodedPointer(&Offset, Cie->getFDEPointerEncoding(), |
| EHFrameAddress + Offset)) { |
| InitialLocation = *Val; |
| } |
| if (auto Val = Data.getEncodedPointer( |
| &Offset, Cie->getFDEPointerEncoding(), 0)) { |
| AddressRange = *Val; |
| } |
| |
| StringRef AugmentationString = Cie->getAugmentationString(); |
| if (!AugmentationString.empty()) { |
| // Parse the augmentation length and data for this FDE. |
| uint64_t AugmentationLength = Data.getULEB128(&Offset); |
| |
| uint64_t EndAugmentationOffset = Offset + AugmentationLength; |
| |
| // Decode the LSDA if the CIE augmentation string said we should. |
| if (Cie->getLSDAPointerEncoding() != DW_EH_PE_omit) { |
| LSDAAddress = Data.getEncodedPointer( |
| &Offset, Cie->getLSDAPointerEncoding(), |
| EHFrameAddress ? Offset + EHFrameAddress : 0); |
| } |
| |
| if (Offset != EndAugmentationOffset) |
| return createStringError(errc::invalid_argument, |
| "parsing augmentation data at 0x%" PRIx64 |
| " failed", |
| StartOffset); |
| } |
| } else { |
| InitialLocation = Data.getRelocatedAddress(&Offset); |
| AddressRange = Data.getRelocatedAddress(&Offset); |
| } |
| |
| Entries.emplace_back(new FDE(IsDWARF64, StartOffset, Length, CIEPointer, |
| InitialLocation, AddressRange, Cie, |
| LSDAAddress, Arch)); |
| } |
| |
| if (Error E = |
| Entries.back()->cfis().parse(Data, &Offset, EndStructureOffset)) |
| return E; |
| |
| if (Offset != EndStructureOffset) |
| return createStringError( |
| errc::invalid_argument, |
| "parsing entry instructions at 0x%" PRIx64 " failed", StartOffset); |
| } |
| |
| return Error::success(); |
| } |
| |
| FrameEntry *DWARFDebugFrame::getEntryAtOffset(uint64_t Offset) const { |
| auto It = partition_point(Entries, [=](const std::unique_ptr<FrameEntry> &E) { |
| return E->getOffset() < Offset; |
| }); |
| if (It != Entries.end() && (*It)->getOffset() == Offset) |
| return It->get(); |
| return nullptr; |
| } |
| |
| void DWARFDebugFrame::dump(raw_ostream &OS, DIDumpOptions DumpOpts, |
| std::optional<uint64_t> Offset) const { |
| DumpOpts.IsEH = IsEH; |
| if (Offset) { |
| if (auto *Entry = getEntryAtOffset(*Offset)) |
| Entry->dump(OS, DumpOpts); |
| return; |
| } |
| |
| OS << "\n"; |
| for (const auto &Entry : Entries) |
| Entry->dump(OS, DumpOpts); |
| } |
