llvm-project/llvm/lib/DebugInfo/DWARF/DWARFDebugRnglists.cpp

250 lines
9.9 KiB
C++

//===- DWARFDebugRnglists.cpp ---------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/DebugInfo/DWARF/DWARFDebugRnglists.h"
#include "llvm/BinaryFormat/Dwarf.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
void DWARFDebugRnglists::clear() {
HeaderData = {};
Offsets.clear();
Ranges.clear();
}
template <typename... Ts>
static Error createError(char const *Fmt, const Ts &... Vals) {
std::string Buffer;
raw_string_ostream Stream(Buffer);
Stream << format(Fmt, Vals...);
return make_error<StringError>(Stream.str(), inconvertibleErrorCode());
}
Error DWARFDebugRnglists::extract(DWARFDataExtractor Data,
uint32_t *OffsetPtr) {
clear();
HeaderOffset = *OffsetPtr;
// Read and verify the length field.
if (!Data.isValidOffsetForDataOfSize(*OffsetPtr, sizeof(uint32_t)))
return createError("section is not large enough to contain a "
".debug_rnglists table length at offset 0x%" PRIx32,
*OffsetPtr);
// TODO: Add support for DWARF64.
HeaderData.Length = Data.getU32(OffsetPtr);
if (HeaderData.Length == 0xffffffffu)
return createError(
"DWARF64 is not supported in .debug_rnglists at offset 0x%" PRIx32,
HeaderOffset);
if (HeaderData.Length + sizeof(uint32_t) < sizeof(Header))
return createError(".debug_rnglists table at offset 0x%" PRIx32
" has too small length (0x%" PRIx32
") to contain a complete header",
HeaderOffset, length());
uint32_t End = HeaderOffset + length();
if (!Data.isValidOffsetForDataOfSize(HeaderOffset, End - HeaderOffset))
return createError(
"section is not large enough to contain a .debug_rnglists table "
"of length 0x%" PRIx32 " at offset 0x%" PRIx32,
length(), HeaderOffset);
HeaderData.Version = Data.getU16(OffsetPtr);
HeaderData.AddrSize = Data.getU8(OffsetPtr);
HeaderData.SegSize = Data.getU8(OffsetPtr);
HeaderData.OffsetEntryCount = Data.getU32(OffsetPtr);
// Perform basic validation of the remaining header fields.
if (HeaderData.Version != 5)
return createError("unrecognised .debug_rnglists table version %" PRIu16
" in table at offset 0x%" PRIx32,
HeaderData.Version, HeaderOffset);
if (HeaderData.AddrSize != 4 && HeaderData.AddrSize != 8)
return createError(".debug_rnglists table at offset 0x%" PRIx32
" has unsupported address size %hhu",
HeaderOffset, HeaderData.AddrSize);
if (HeaderData.SegSize != 0)
return createError(".debug_rnglists table at offset 0x%" PRIx32
" has unsupported segment selector size %" PRIu8,
HeaderOffset, HeaderData.SegSize);
if (End < HeaderOffset + sizeof(HeaderData) +
HeaderData.OffsetEntryCount * sizeof(uint32_t))
return createError(".debug_rnglists table at offset 0x%" PRIx32
" has more offset entries (%" PRIu32
") than there is space for",
HeaderOffset, HeaderData.OffsetEntryCount);
Data.setAddressSize(HeaderData.AddrSize);
for (uint32_t I = 0; I < HeaderData.OffsetEntryCount; ++I)
Offsets.push_back(Data.getU32(OffsetPtr));
DWARFRangeList CurrentRanges;
while (*OffsetPtr < End) {
uint32_t EntryOffset = *OffsetPtr;
uint8_t Encoding = Data.getU8(OffsetPtr);
MaxEncodingStringLength =
std::max(MaxEncodingStringLength,
(uint8_t)dwarf::RangeListEncodingString(Encoding).size());
switch (Encoding) {
case dwarf::DW_RLE_end_of_list:
CurrentRanges.push_back(RangeListEntry{ EntryOffset, Encoding, 0, 0 });
Ranges.insert(Ranges.end(), std::move(CurrentRanges));
CurrentRanges.clear();
break;
// TODO: Support other encodings.
case dwarf::DW_RLE_base_addressx:
return createError("unsupported rnglists encoding DW_RLE_base_addressx "
"at offset 0x%" PRIx32,
*OffsetPtr - 1);
case dwarf::DW_RLE_startx_endx:
return createError("unsupported rnglists encoding DW_RLE_startx_endx at "
"offset 0x%" PRIx32,
*OffsetPtr - 1);
case dwarf::DW_RLE_startx_length:
return createError("unsupported rnglists encoding DW_RLE_startx_length "
"at offset 0x%" PRIx32,
*OffsetPtr - 1);
case dwarf::DW_RLE_offset_pair:
return createError("unsupported rnglists encoding DW_RLE_offset_pair at "
"offset 0x%" PRIx32,
*OffsetPtr - 1);
case dwarf::DW_RLE_base_address:
return createError("unsupported rnglists encoding DW_RLE_base_address at "
"offset 0x%" PRIx32,
*OffsetPtr - 1);
case dwarf::DW_RLE_start_end: {
if ((End - *OffsetPtr) < unsigned(HeaderData.AddrSize * 2))
return createError("insufficient space remaining in table for "
"DW_RLE_start_end encoding "
"at offset 0x%" PRIx32,
*OffsetPtr - 1);
uint64_t Start = Data.getAddress(OffsetPtr);
uint64_t End = Data.getAddress(OffsetPtr);
CurrentRanges.push_back(
RangeListEntry{EntryOffset, Encoding, Start, End});
break;
}
case dwarf::DW_RLE_start_length: {
uint32_t PreviousOffset = *OffsetPtr - 1;
uint64_t Start = Data.getAddress(OffsetPtr);
uint64_t Length = Data.getULEB128(OffsetPtr);
if (End < *OffsetPtr)
return createError("read past end of table when reading "
"DW_RLE_start_length encoding at offset 0x%" PRIx32,
PreviousOffset);
CurrentRanges.push_back(
RangeListEntry{EntryOffset, Encoding, Start, Length});
break;
}
default:
Ranges.insert(Ranges.end(), std::move(CurrentRanges));
return createError("unknown rnglists encoding 0x%" PRIx32
" at offset 0x%" PRIx32,
uint32_t(Encoding), *OffsetPtr - 1);
}
}
// If OffsetPtr does not indicate the End offset, then either the above loop
// terminated prematurely, or we encountered a malformed encoding, but did not
// report an error when we should have done.
assert(*OffsetPtr == End &&
"did not detect malformed data or loop ended unexpectedly");
// If CurrentRanges is not empty, we have a malformed section, because we did
// not find a DW_RLE_end_of_list marker at the end of the last list.
if (!CurrentRanges.empty())
return createError(
"no end of list marker detected at end of .debug_rnglists table "
"starting at offset 0x%" PRIx32,
HeaderOffset);
return Error::success();
}
static void dumpRangeEntry(raw_ostream &OS,
DWARFDebugRnglists::RangeListEntry Entry,
uint8_t AddrSize, uint8_t MaxEncodingStringLength,
DIDumpOptions DumpOpts) {
if (DumpOpts.Verbose) {
// Print the section offset in verbose mode.
OS << format("0x%8.8" PRIx32 ":", Entry.Offset);
auto EncodingString = dwarf::RangeListEncodingString(Entry.EntryKind);
// Unsupported encodings should have been reported during parsing.
assert(!EncodingString.empty() && "Unknown range entry encoding");
OS << format(" [%s%*c", EncodingString.data(),
MaxEncodingStringLength - EncodingString.size() + 1, ']');
if (Entry.EntryKind != dwarf::DW_RLE_end_of_list)
OS << ": ";
}
switch (Entry.EntryKind) {
case dwarf::DW_RLE_end_of_list:
OS << (DumpOpts.Verbose ? "" : "<End of list>");
break;
case dwarf::DW_RLE_start_length:
if (DumpOpts.Verbose) {
// Make the address range display its contents in raw form rather than
// as an interval (i.e. without brackets).
DumpOpts.DisplayRawContents = true;
DWARFAddressRange(Entry.Value0, Entry.Value1)
.dump(OS, AddrSize, DumpOpts);
OS << " => ";
}
DumpOpts.DisplayRawContents = false;
DWARFAddressRange(Entry.Value0, Entry.Value0 + Entry.Value1)
.dump(OS, AddrSize, DumpOpts);
break;
case dwarf::DW_RLE_start_end:
DWARFAddressRange(Entry.Value0, Entry.Value1).dump(OS, AddrSize, DumpOpts);
break;
default:
llvm_unreachable("Unsupported range list encoding");
}
OS << "\n";
}
void DWARFDebugRnglists::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const {
if (DumpOpts.Verbose)
OS << format("0x%8.8" PRIx32 ": ", HeaderOffset);
OS << format("Range List Header: length = 0x%8.8" PRIx32
", version = 0x%4.4" PRIx16 ", "
"addr_size = 0x%2.2" PRIx8 ", seg_size = 0x%2.2" PRIx8
", offset_entry_count = "
"0x%8.8" PRIx32 "\n",
HeaderData.Length, HeaderData.Version, HeaderData.AddrSize,
HeaderData.SegSize, HeaderData.OffsetEntryCount);
if (HeaderData.OffsetEntryCount > 0) {
OS << "Offsets: [";
for (const auto &Off : Offsets) {
OS << format("\n0x%8.8" PRIx32, Off);
if (DumpOpts.Verbose)
OS << format(" => 0x%8.8" PRIx32,
Off + HeaderOffset + sizeof(HeaderData));
}
OS << "\n]\n";
}
OS << "Ranges:\n";
for (const auto &List : Ranges)
for (const auto &Entry : List)
dumpRangeEntry(OS, Entry, HeaderData.AddrSize, MaxEncodingStringLength,
DumpOpts);
}
uint32_t DWARFDebugRnglists::length() const {
if (HeaderData.Length == 0)
return 0;
// TODO: DWARF64 support.
return HeaderData.Length + sizeof(uint32_t);
}