Revert "[NFC] Refactor symbol table parsing."
This reverts commit 951b107eed.
Buildbots were failing, there is a deadlock in /Users/gclayton/Documents/src/llvm/clean/llvm-project/lldb/test/Shell/SymbolFile/DWARF/DW_AT_range-DW_FORM_sec_offset.s when ELF files try to relocate things.
This commit is contained in:
Greg Clayton
@@ -2687,132 +2687,155 @@ unsigned ObjectFileELF::RelocateDebugSections(const ELFSectionHeader *rel_hdr,
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return 0;
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}
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void ObjectFileELF::ParseSymtab(Symtab &lldb_symtab) {
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Symtab *ObjectFileELF::GetSymtab() {
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ModuleSP module_sp(GetModule());
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if (!module_sp)
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return;
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Progress progress(
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llvm::formatv("Parsing symbol table for {0}",
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m_file.GetFilename().AsCString("<Unknown>")));
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ElapsedTime elapsed(module_sp->GetSymtabParseTime());
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return nullptr;
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// We always want to use the main object file so we (hopefully) only have one
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// cached copy of our symtab, dynamic sections, etc.
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ObjectFile *module_obj_file = module_sp->GetObjectFile();
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if (module_obj_file && module_obj_file != this)
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return module_obj_file->ParseSymtab(lldb_symtab);
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return module_obj_file->GetSymtab();
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SectionList *section_list = module_sp->GetSectionList();
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if (!section_list)
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return;
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if (m_symtab_up == nullptr) {
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Progress progress(
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llvm::formatv("Parsing symbol table for {0}",
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m_file.GetFilename().AsCString("<Unknown>")));
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ElapsedTime elapsed(module_sp->GetSymtabParseTime());
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SectionList *section_list = module_sp->GetSectionList();
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if (!section_list)
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return nullptr;
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uint64_t symbol_id = 0;
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std::lock_guard<std::recursive_mutex> guard(module_sp->GetMutex());
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uint64_t symbol_id = 0;
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std::lock_guard<std::recursive_mutex> guard(module_sp->GetMutex());
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// Sharable objects and dynamic executables usually have 2 distinct symbol
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// tables, one named ".symtab", and the other ".dynsym". The dynsym is a
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// smaller version of the symtab that only contains global symbols. The
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// information found in the dynsym is therefore also found in the symtab,
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// while the reverse is not necessarily true.
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Section *symtab =
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section_list->FindSectionByType(eSectionTypeELFSymbolTable, true).get();
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if (symtab)
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symbol_id += ParseSymbolTable(&lldb_symtab, symbol_id, symtab);
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// The symtab section is non-allocable and can be stripped, while the
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// .dynsym section which should always be always be there. To support the
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// minidebuginfo case we parse .dynsym when there's a .gnu_debuginfo
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// section, nomatter if .symtab was already parsed or not. This is because
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// minidebuginfo normally removes the .symtab symbols which have their
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// matching .dynsym counterparts.
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if (!symtab ||
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GetSectionList()->FindSectionByName(ConstString(".gnu_debugdata"))) {
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Section *dynsym =
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section_list->FindSectionByType(eSectionTypeELFDynamicSymbols, true)
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.get();
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if (dynsym)
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symbol_id += ParseSymbolTable(&lldb_symtab, symbol_id, dynsym);
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}
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// DT_JMPREL
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// If present, this entry's d_ptr member holds the address of
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// relocation
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// entries associated solely with the procedure linkage table.
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// Separating
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// these relocation entries lets the dynamic linker ignore them during
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// process initialization, if lazy binding is enabled. If this entry is
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// present, the related entries of types DT_PLTRELSZ and DT_PLTREL must
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// also be present.
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const ELFDynamic *symbol = FindDynamicSymbol(DT_JMPREL);
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if (symbol) {
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// Synthesize trampoline symbols to help navigate the PLT.
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addr_t addr = symbol->d_ptr;
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Section *reloc_section =
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section_list->FindSectionContainingFileAddress(addr).get();
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if (reloc_section) {
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user_id_t reloc_id = reloc_section->GetID();
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const ELFSectionHeaderInfo *reloc_header =
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GetSectionHeaderByIndex(reloc_id);
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if (reloc_header)
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ParseTrampolineSymbols(&lldb_symtab, symbol_id, reloc_header, reloc_id);
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// Sharable objects and dynamic executables usually have 2 distinct symbol
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// tables, one named ".symtab", and the other ".dynsym". The dynsym is a
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// smaller version of the symtab that only contains global symbols. The
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// information found in the dynsym is therefore also found in the symtab,
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// while the reverse is not necessarily true.
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Section *symtab =
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section_list->FindSectionByType(eSectionTypeELFSymbolTable, true).get();
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if (symtab) {
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m_symtab_up = std::make_unique<Symtab>(symtab->GetObjectFile());
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symbol_id += ParseSymbolTable(m_symtab_up.get(), symbol_id, symtab);
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}
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}
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if (DWARFCallFrameInfo *eh_frame =
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GetModule()->GetUnwindTable().GetEHFrameInfo()) {
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ParseUnwindSymbols(&lldb_symtab, eh_frame);
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}
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// In the event that there's no symbol entry for the entry point we'll
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// artificially create one. We delegate to the symtab object the figuring
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// out of the proper size, this will usually make it span til the next
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// symbol it finds in the section. This means that if there are missing
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// symbols the entry point might span beyond its function definition.
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// We're fine with this as it doesn't make it worse than not having a
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// symbol entry at all.
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if (CalculateType() == eTypeExecutable) {
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ArchSpec arch = GetArchitecture();
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auto entry_point_addr = GetEntryPointAddress();
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bool is_valid_entry_point =
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entry_point_addr.IsValid() && entry_point_addr.IsSectionOffset();
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addr_t entry_point_file_addr = entry_point_addr.GetFileAddress();
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if (is_valid_entry_point && !lldb_symtab.FindSymbolContainingFileAddress(
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entry_point_file_addr)) {
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uint64_t symbol_id = lldb_symtab.GetNumSymbols();
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// Don't set the name for any synthetic symbols, the Symbol
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// object will generate one if needed when the name is accessed
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// via accessors.
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SectionSP section_sp = entry_point_addr.GetSection();
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Symbol symbol(
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/*symID=*/symbol_id,
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/*name=*/llvm::StringRef(), // Name will be auto generated.
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/*type=*/eSymbolTypeCode,
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/*external=*/true,
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/*is_debug=*/false,
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/*is_trampoline=*/false,
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/*is_artificial=*/true,
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/*section_sp=*/section_sp,
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/*offset=*/0,
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/*size=*/0, // FDE can span multiple symbols so don't use its size.
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/*size_is_valid=*/false,
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/*contains_linker_annotations=*/false,
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/*flags=*/0);
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// When the entry point is arm thumb we need to explicitly set its
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// class address to reflect that. This is important because expression
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// evaluation relies on correctly setting a breakpoint at this
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// address.
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if (arch.GetMachine() == llvm::Triple::arm &&
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(entry_point_file_addr & 1)) {
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symbol.GetAddressRef().SetOffset(entry_point_addr.GetOffset() ^ 1);
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m_address_class_map[entry_point_file_addr ^ 1] =
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AddressClass::eCodeAlternateISA;
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} else {
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m_address_class_map[entry_point_file_addr] = AddressClass::eCode;
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// The symtab section is non-allocable and can be stripped, while the
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// .dynsym section which should always be always be there. To support the
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// minidebuginfo case we parse .dynsym when there's a .gnu_debuginfo
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// section, nomatter if .symtab was already parsed or not. This is because
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// minidebuginfo normally removes the .symtab symbols which have their
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// matching .dynsym counterparts.
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if (!symtab ||
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GetSectionList()->FindSectionByName(ConstString(".gnu_debugdata"))) {
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Section *dynsym =
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section_list->FindSectionByType(eSectionTypeELFDynamicSymbols, true)
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.get();
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if (dynsym) {
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if (!m_symtab_up)
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m_symtab_up = std::make_unique<Symtab>(dynsym->GetObjectFile());
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symbol_id += ParseSymbolTable(m_symtab_up.get(), symbol_id, dynsym);
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}
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lldb_symtab.AddSymbol(symbol);
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}
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// DT_JMPREL
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// If present, this entry's d_ptr member holds the address of
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// relocation
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// entries associated solely with the procedure linkage table.
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// Separating
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// these relocation entries lets the dynamic linker ignore them during
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// process initialization, if lazy binding is enabled. If this entry is
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// present, the related entries of types DT_PLTRELSZ and DT_PLTREL must
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// also be present.
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const ELFDynamic *symbol = FindDynamicSymbol(DT_JMPREL);
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if (symbol) {
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// Synthesize trampoline symbols to help navigate the PLT.
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addr_t addr = symbol->d_ptr;
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Section *reloc_section =
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section_list->FindSectionContainingFileAddress(addr).get();
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if (reloc_section) {
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user_id_t reloc_id = reloc_section->GetID();
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const ELFSectionHeaderInfo *reloc_header =
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GetSectionHeaderByIndex(reloc_id);
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if (reloc_header) {
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if (m_symtab_up == nullptr)
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m_symtab_up =
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std::make_unique<Symtab>(reloc_section->GetObjectFile());
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ParseTrampolineSymbols(m_symtab_up.get(), symbol_id, reloc_header,
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reloc_id);
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}
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}
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}
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if (DWARFCallFrameInfo *eh_frame =
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GetModule()->GetUnwindTable().GetEHFrameInfo()) {
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if (m_symtab_up == nullptr)
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m_symtab_up = std::make_unique<Symtab>(this);
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ParseUnwindSymbols(m_symtab_up.get(), eh_frame);
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}
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// If we still don't have any symtab then create an empty instance to avoid
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// do the section lookup next time.
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if (m_symtab_up == nullptr)
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m_symtab_up = std::make_unique<Symtab>(this);
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// In the event that there's no symbol entry for the entry point we'll
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// artificially create one. We delegate to the symtab object the figuring
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// out of the proper size, this will usually make it span til the next
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// symbol it finds in the section. This means that if there are missing
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// symbols the entry point might span beyond its function definition.
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// We're fine with this as it doesn't make it worse than not having a
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// symbol entry at all.
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if (CalculateType() == eTypeExecutable) {
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ArchSpec arch = GetArchitecture();
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auto entry_point_addr = GetEntryPointAddress();
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bool is_valid_entry_point =
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entry_point_addr.IsValid() && entry_point_addr.IsSectionOffset();
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addr_t entry_point_file_addr = entry_point_addr.GetFileAddress();
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if (is_valid_entry_point && !m_symtab_up->FindSymbolContainingFileAddress(
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entry_point_file_addr)) {
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uint64_t symbol_id = m_symtab_up->GetNumSymbols();
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// Don't set the name for any synthetic symbols, the Symbol
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// object will generate one if needed when the name is accessed
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// via accessors.
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SectionSP section_sp = entry_point_addr.GetSection();
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Symbol symbol(
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/*symID=*/symbol_id,
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/*name=*/llvm::StringRef(), // Name will be auto generated.
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/*type=*/eSymbolTypeCode,
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/*external=*/true,
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/*is_debug=*/false,
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/*is_trampoline=*/false,
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/*is_artificial=*/true,
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/*section_sp=*/section_sp,
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/*offset=*/0,
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/*size=*/0, // FDE can span multiple symbols so don't use its size.
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/*size_is_valid=*/false,
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/*contains_linker_annotations=*/false,
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/*flags=*/0);
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// When the entry point is arm thumb we need to explicitly set its
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// class address to reflect that. This is important because expression
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// evaluation relies on correctly setting a breakpoint at this
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// address.
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if (arch.GetMachine() == llvm::Triple::arm &&
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(entry_point_file_addr & 1)) {
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symbol.GetAddressRef().SetOffset(entry_point_addr.GetOffset() ^ 1);
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m_address_class_map[entry_point_file_addr ^ 1] =
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AddressClass::eCodeAlternateISA;
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} else {
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m_address_class_map[entry_point_file_addr] = AddressClass::eCode;
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}
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m_symtab_up->AddSymbol(symbol);
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}
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}
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m_symtab_up->CalculateSymbolSizes();
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}
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return m_symtab_up.get();
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}
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void ObjectFileELF::RelocateSection(lldb_private::Section *section)
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