diff options
Diffstat (limited to 'llvm/lib/DebugInfo/DWARF/DWARFDebugLoc.cpp')
| -rw-r--r-- | llvm/lib/DebugInfo/DWARF/DWARFDebugLoc.cpp | 339 |
1 files changed, 339 insertions, 0 deletions
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugLoc.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugLoc.cpp new file mode 100644 index 0000000000000..4f7b01130a478 --- /dev/null +++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugLoc.cpp @@ -0,0 +1,339 @@ +//===- DWARFDebugLoc.cpp --------------------------------------------------===// +// +// 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/DWARFDebugLoc.h" +#include "llvm/ADT/StringRef.h" +#include "llvm/BinaryFormat/Dwarf.h" +#include "llvm/DebugInfo/DWARF/DWARFContext.h" +#include "llvm/DebugInfo/DWARF/DWARFExpression.h" +#include "llvm/DebugInfo/DWARF/DWARFRelocMap.h" +#include "llvm/DebugInfo/DWARF/DWARFUnit.h" +#include "llvm/Support/Compiler.h" +#include "llvm/Support/Format.h" +#include "llvm/Support/WithColor.h" +#include "llvm/Support/raw_ostream.h" +#include <algorithm> +#include <cinttypes> +#include <cstdint> + +using namespace llvm; + +// When directly dumping the .debug_loc without a compile unit, we have to guess +// at the DWARF version. This only affects DW_OP_call_ref, which is a rare +// expression that LLVM doesn't produce. Guessing the wrong version means we +// won't be able to pretty print expressions in DWARF2 binaries produced by +// non-LLVM tools. +static void dumpExpression(raw_ostream &OS, ArrayRef<uint8_t> Data, + bool IsLittleEndian, unsigned AddressSize, + const MCRegisterInfo *MRI, DWARFUnit *U) { + DWARFDataExtractor Extractor(toStringRef(Data), IsLittleEndian, AddressSize); + DWARFExpression(Extractor, dwarf::DWARF_VERSION, AddressSize).print(OS, MRI, U); +} + +void DWARFDebugLoc::LocationList::dump(raw_ostream &OS, uint64_t BaseAddress, + bool IsLittleEndian, + unsigned AddressSize, + const MCRegisterInfo *MRI, DWARFUnit *U, + DIDumpOptions DumpOpts, + unsigned Indent) const { + for (const Entry &E : Entries) { + OS << '\n'; + OS.indent(Indent); + OS << format("[0x%*.*" PRIx64 ", ", AddressSize * 2, AddressSize * 2, + BaseAddress + E.Begin); + OS << format(" 0x%*.*" PRIx64 ")", AddressSize * 2, AddressSize * 2, + BaseAddress + E.End); + OS << ": "; + + dumpExpression(OS, E.Loc, IsLittleEndian, AddressSize, MRI, U); + } +} + +DWARFDebugLoc::LocationList const * +DWARFDebugLoc::getLocationListAtOffset(uint64_t Offset) const { + auto It = partition_point( + Locations, [=](const LocationList &L) { return L.Offset < Offset; }); + if (It != Locations.end() && It->Offset == Offset) + return &(*It); + return nullptr; +} + +void DWARFDebugLoc::dump(raw_ostream &OS, const MCRegisterInfo *MRI, DIDumpOptions DumpOpts, + Optional<uint64_t> Offset) const { + auto DumpLocationList = [&](const LocationList &L) { + OS << format("0x%8.8" PRIx64 ": ", L.Offset); + L.dump(OS, 0, IsLittleEndian, AddressSize, MRI, nullptr, DumpOpts, 12); + OS << "\n"; + }; + + if (Offset) { + if (auto *L = getLocationListAtOffset(*Offset)) + DumpLocationList(*L); + return; + } + + for (const LocationList &L : Locations) { + DumpLocationList(L); + if (&L != &Locations.back()) + OS << '\n'; + } +} + +Expected<DWARFDebugLoc::LocationList> +DWARFDebugLoc::parseOneLocationList(const DWARFDataExtractor &Data, + uint64_t *Offset) { + LocationList LL; + LL.Offset = *Offset; + AddressSize = Data.getAddressSize(); + DataExtractor::Cursor C(*Offset); + + // 2.6.2 Location Lists + // A location list entry consists of: + while (true) { + Entry E; + + // 1. A beginning address offset. ... + E.Begin = Data.getRelocatedAddress(C); + + // 2. An ending address offset. ... + E.End = Data.getRelocatedAddress(C); + + if (Error Err = C.takeError()) + return std::move(Err); + + // The end of any given location list is marked by an end of list entry, + // which consists of a 0 for the beginning address offset and a 0 for the + // ending address offset. + if (E.Begin == 0 && E.End == 0) { + *Offset = C.tell(); + return LL; + } + + if (E.Begin != (AddressSize == 4 ? -1U : -1ULL)) { + unsigned Bytes = Data.getU16(C); + // A single location description describing the location of the object... + Data.getU8(C, E.Loc, Bytes); + } + + LL.Entries.push_back(std::move(E)); + } +} + +void DWARFDebugLoc::parse(const DWARFDataExtractor &data) { + IsLittleEndian = data.isLittleEndian(); + AddressSize = data.getAddressSize(); + + uint64_t Offset = 0; + while (Offset < data.getData().size()) { + if (auto LL = parseOneLocationList(data, &Offset)) + Locations.push_back(std::move(*LL)); + else { + logAllUnhandledErrors(LL.takeError(), WithColor::error()); + break; + } + } +} + +Expected<DWARFDebugLoclists::LocationList> +DWARFDebugLoclists::parseOneLocationList(const DataExtractor &Data, + uint64_t *Offset, unsigned Version) { + LocationList LL; + LL.Offset = *Offset; + DataExtractor::Cursor C(*Offset); + + // dwarf::DW_LLE_end_of_list_entry is 0 and indicates the end of the list. + while (auto Kind = Data.getU8(C)) { + Entry E; + E.Kind = Kind; + E.Offset = C.tell() - 1; + switch (Kind) { + case dwarf::DW_LLE_base_addressx: + E.Value0 = Data.getULEB128(C); + break; + case dwarf::DW_LLE_startx_length: + E.Value0 = Data.getULEB128(C); + // Pre-DWARF 5 has different interpretation of the length field. We have + // to support both pre- and standartized styles for the compatibility. + if (Version < 5) + E.Value1 = Data.getU32(C); + else + E.Value1 = Data.getULEB128(C); + break; + case dwarf::DW_LLE_start_length: + E.Value0 = Data.getAddress(C); + E.Value1 = Data.getULEB128(C); + break; + case dwarf::DW_LLE_offset_pair: + E.Value0 = Data.getULEB128(C); + E.Value1 = Data.getULEB128(C); + break; + case dwarf::DW_LLE_base_address: + E.Value0 = Data.getAddress(C); + break; + default: + cantFail(C.takeError()); + return createStringError(errc::illegal_byte_sequence, + "LLE of kind %x not supported", (int)Kind); + } + + if (Kind != dwarf::DW_LLE_base_address && + Kind != dwarf::DW_LLE_base_addressx) { + unsigned Bytes = Version >= 5 ? Data.getULEB128(C) : Data.getU16(C); + // A single location description describing the location of the object... + Data.getU8(C, E.Loc, Bytes); + } + + LL.Entries.push_back(std::move(E)); + } + if (Error Err = C.takeError()) + return std::move(Err); + Entry E; + E.Kind = dwarf::DW_LLE_end_of_list; + E.Offset = C.tell() - 1; + LL.Entries.push_back(E); + *Offset = C.tell(); + return LL; +} + +void DWARFDebugLoclists::parse(DataExtractor data, uint64_t Offset, uint64_t EndOffset, uint16_t Version) { + IsLittleEndian = data.isLittleEndian(); + AddressSize = data.getAddressSize(); + + while (Offset < EndOffset) { + if (auto LL = parseOneLocationList(data, &Offset, Version)) + Locations.push_back(std::move(*LL)); + else { + logAllUnhandledErrors(LL.takeError(), WithColor::error()); + return; + } + } +} + +DWARFDebugLoclists::LocationList const * +DWARFDebugLoclists::getLocationListAtOffset(uint64_t Offset) const { + auto It = partition_point( + Locations, [=](const LocationList &L) { return L.Offset < Offset; }); + if (It != Locations.end() && It->Offset == Offset) + return &(*It); + return nullptr; +} + +void DWARFDebugLoclists::Entry::dump(raw_ostream &OS, uint64_t &BaseAddr, + bool IsLittleEndian, unsigned AddressSize, + const MCRegisterInfo *MRI, DWARFUnit *U, + DIDumpOptions DumpOpts, unsigned Indent, + size_t MaxEncodingStringLength) const { + if (DumpOpts.Verbose) { + OS << "\n"; + OS.indent(Indent); + auto EncodingString = dwarf::LocListEncodingString(Kind); + // Unsupported encodings should have been reported during parsing. + assert(!EncodingString.empty() && "Unknown loclist entry encoding"); + OS << format("%s%*c", EncodingString.data(), + MaxEncodingStringLength - EncodingString.size() + 1, '('); + switch (Kind) { + case dwarf::DW_LLE_startx_length: + case dwarf::DW_LLE_start_length: + case dwarf::DW_LLE_offset_pair: + OS << format("0x%*.*" PRIx64 ", 0x%*.*" PRIx64, AddressSize * 2, + AddressSize * 2, Value0, AddressSize * 2, AddressSize * 2, + Value1); + break; + case dwarf::DW_LLE_base_addressx: + case dwarf::DW_LLE_base_address: + OS << format("0x%*.*" PRIx64, AddressSize * 2, AddressSize * 2, + Value0); + break; + case dwarf::DW_LLE_end_of_list: + break; + } + OS << ')'; + } + auto PrintPrefix = [&] { + OS << "\n"; + OS.indent(Indent); + if (DumpOpts.Verbose) + OS << format("%*s", MaxEncodingStringLength, (const char *)"=> "); + }; + switch (Kind) { + case dwarf::DW_LLE_startx_length: + PrintPrefix(); + OS << "Addr idx " << Value0 << " (w/ length " << Value1 << "): "; + break; + case dwarf::DW_LLE_start_length: + PrintPrefix(); + DWARFAddressRange(Value0, Value0 + Value1) + .dump(OS, AddressSize, DumpOpts); + OS << ": "; + break; + case dwarf::DW_LLE_offset_pair: + PrintPrefix(); + DWARFAddressRange(BaseAddr + Value0, BaseAddr + Value1) + .dump(OS, AddressSize, DumpOpts); + OS << ": "; + break; + case dwarf::DW_LLE_base_addressx: + if (!DumpOpts.Verbose) + return; + break; + case dwarf::DW_LLE_end_of_list: + if (!DumpOpts.Verbose) + return; + break; + case dwarf::DW_LLE_base_address: + BaseAddr = Value0; + if (!DumpOpts.Verbose) + return; + break; + default: + llvm_unreachable("unreachable locations list kind"); + } + + dumpExpression(OS, Loc, IsLittleEndian, AddressSize, MRI, U); +} +void DWARFDebugLoclists::LocationList::dump(raw_ostream &OS, uint64_t BaseAddr, + bool IsLittleEndian, + unsigned AddressSize, + const MCRegisterInfo *MRI, + DWARFUnit *U, + DIDumpOptions DumpOpts, + unsigned Indent) const { + size_t MaxEncodingStringLength = 0; + if (DumpOpts.Verbose) + for (const auto &Entry : Entries) + MaxEncodingStringLength = + std::max(MaxEncodingStringLength, + dwarf::LocListEncodingString(Entry.Kind).size()); + + for (const Entry &E : Entries) + E.dump(OS, BaseAddr, IsLittleEndian, AddressSize, MRI, U, DumpOpts, Indent, + MaxEncodingStringLength); +} + +void DWARFDebugLoclists::dump(raw_ostream &OS, uint64_t BaseAddr, + const MCRegisterInfo *MRI, DIDumpOptions DumpOpts, + Optional<uint64_t> Offset) const { + auto DumpLocationList = [&](const LocationList &L) { + OS << format("0x%8.8" PRIx64 ": ", L.Offset); + L.dump(OS, BaseAddr, IsLittleEndian, AddressSize, MRI, nullptr, DumpOpts, + /*Indent=*/12); + OS << "\n"; + }; + + if (Offset) { + if (auto *L = getLocationListAtOffset(*Offset)) + DumpLocationList(*L); + return; + } + + for (const LocationList &L : Locations) { + DumpLocationList(L); + if (&L != &Locations.back()) + OS << '\n'; + } +} |