caio/clang-p2996
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

<rdar://problem/10103468>

Browse Source 
I started work on being able to add symbol files after a debug session
had started with a new "target symfile add" command and quickly ran into
problems with stale Address objects in breakpoint locations that had 
lldb_private::Section pointers into modules that had been removed or 
replaced. This also let to grabbing stale modules from those sections. 
So I needed to thread harded the Address, Section and related objects.

To do this I modified the ModuleChild class to now require a ModuleSP
on initialization so that a weak reference can created. I also changed
all places that were handing out "Section *" to have them hand out SectionSP.
All ObjectFile, SymbolFile and SymbolVendors were inheriting from ModuleChild
so all of the find plug-in, static creation function and constructors now
require ModuleSP references instead of Module *. 

Address objects now have weak references to their sections which can
safely go stale when a module gets destructed. 

This checkin doesn't complete the "target symfile add" command, but it
does get us a lot clioser to being able to do such things without a high
risk of crashing or memory corruption.

llvm-svn: 151336
This commit is contained in:
Greg Clayton
2012-02-24 01:59:29 +00:00
parent da97054114
commit e72dfb321c
90 changed files with 1357 additions and 1027 deletions
Download Patch File Download Diff File Expand all files Collapse all files

125
lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
View File

@@ -171,10 +171,11 @@ ObjectFileELF::GetPluginDescriptionStatic()
}
ObjectFile *
ObjectFileELF::CreateInstance(Module *module,
DataBufferSP &data_sp,
const FileSpec *file, addr_t offset,
addr_t length)
ObjectFileELF::CreateInstance (const lldb::ModuleSP &module_sp,
DataBufferSP &data_sp,
const FileSpec *file,
addr_t offset,
addr_t length)
{
if (data_sp && data_sp->GetByteSize() > (llvm::ELF::EI_NIDENT + offset))
{
@@ -184,8 +185,7 @@ ObjectFileELF::CreateInstance(Module *module,
unsigned address_size = ELFHeader::AddressSizeInBytes(magic);
if (address_size == 4 || address_size == 8)
{
std::auto_ptr<ObjectFileELF> objfile_ap(
new ObjectFileELF(module, data_sp, file, offset, length));
std::auto_ptr<ObjectFileELF> objfile_ap(new ObjectFileELF(module_sp, data_sp, file, offset, length));
ArchSpec spec;
if (objfile_ap->GetArchitecture(spec) &&
objfile_ap->SetModulesArchitecture(spec))
@@ -198,7 +198,10 @@ ObjectFileELF::CreateInstance(Module *module,
ObjectFile*
ObjectFileELF::CreateMemoryInstance(Module* module, DataBufferSP& data_sp, const lldb::ProcessSP &process_sp, lldb::addr_t header_addr)
ObjectFileELF::CreateMemoryInstance (const lldb::ModuleSP &module_sp,
DataBufferSP& data_sp,
const lldb::ProcessSP &process_sp,
lldb::addr_t header_addr)
{
return NULL;
}
@@ -228,17 +231,19 @@ ObjectFileELF::GetPluginVersion()
// ObjectFile protocol
//------------------------------------------------------------------
ObjectFileELF::ObjectFileELF(Module* module, DataBufferSP& dataSP,
const FileSpec* file, addr_t offset,
addr_t length)
: ObjectFile(module, file, offset, length, dataSP),
m_header(),
m_program_headers(),
m_section_headers(),
m_sections_ap(),
m_symtab_ap(),
m_filespec_ap(),
m_shstr_data()
ObjectFileELF::ObjectFileELF (const lldb::ModuleSP &module_sp,
DataBufferSP& dataSP,
const FileSpec* file,
addr_t offset,
addr_t length) :
ObjectFile(module_sp, file, offset, length, dataSP),
m_header(),
m_program_headers(),
m_section_headers(),
m_sections_ap(),
m_symtab_ap(),
m_filespec_ap(),
m_shstr_data()
{
if (file)
m_file = *file;
@@ -346,20 +351,20 @@ ObjectFileELF::GetImageInfoAddress()
if (!dynsym_hdr)
return Address();
Section *dynsym = section_list->FindSectionByID(dynsym_id).get();
if (!dynsym)
return Address();
for (size_t i = 0; i < m_dynamic_symbols.size(); ++i)
SectionSP dynsym_section_sp (section_list->FindSectionByID(dynsym_id));
if (dynsym_section_sp)
{
ELFDynamic &symbol = m_dynamic_symbols[i];
if (symbol.d_tag == DT_DEBUG)
for (size_t i = 0; i < m_dynamic_symbols.size(); ++i)
{
// Compute the offset as the number of previous entries plus the
// size of d_tag.
addr_t offset = i * dynsym_hdr->sh_entsize + GetAddressByteSize();
return Address(dynsym, offset);
ELFDynamic &symbol = m_dynamic_symbols[i];
if (symbol.d_tag == DT_DEBUG)
{
// Compute the offset as the number of previous entries plus the
// size of d_tag.
addr_t offset = i * dynsym_hdr->sh_entsize + GetAddressByteSize();
return Address(dynsym_section_sp, offset);
}
}
}
@@ -648,7 +653,6 @@ ObjectFileELF::GetSectionList()
SectionSP section(new Section(
0, // Parent section.
GetModule(), // Module to which this section belongs.
SectionIndex(I), // Section ID.
name, // Section name.
@@ -697,7 +701,7 @@ ParseSymbols(Symtab *symtab,
if (symbol.Parse(symtab_data, &offset) == false)
break;
Section *symbol_section = NULL;
SectionSP symbol_section_sp;
SymbolType symbol_type = eSymbolTypeInvalid;
Elf64_Half symbol_idx = symbol.st_shndx;
@@ -710,7 +714,7 @@ ParseSymbols(Symtab *symtab,
symbol_type = eSymbolTypeUndefined;
break;
default:
symbol_section = section_list->GetSectionAtIndex(symbol_idx).get();
symbol_section_sp = section_list->GetSectionAtIndex(symbol_idx);
break;
}
@@ -749,9 +753,9 @@ ParseSymbols(Symtab *symtab,
if (symbol_type == eSymbolTypeInvalid)
{
if (symbol_section)
if (symbol_section_sp)
{
const ConstString &sect_name = symbol_section->GetName();
const ConstString &sect_name = symbol_section_sp->GetName();
if (sect_name == text_section_name ||
sect_name == init_section_name ||
sect_name == fini_section_name ||
@@ -772,25 +776,25 @@ ParseSymbols(Symtab *symtab,
}
uint64_t symbol_value = symbol.st_value;
if (symbol_section != NULL)
symbol_value -= symbol_section->GetFileAddress();
if (symbol_section_sp)
symbol_value -= symbol_section_sp->GetFileAddress();
const char *symbol_name = strtab_data.PeekCStr(symbol.st_name);
bool is_global = symbol.getBinding() == STB_GLOBAL;
uint32_t flags = symbol.st_other << 8 | symbol.st_info;
Symbol dc_symbol(
i + start_id, // ID is the original symbol table index.
symbol_name, // Symbol name.
false, // Is the symbol name mangled?
symbol_type, // Type of this symbol
is_global, // Is this globally visible?
false, // Is this symbol debug info?
false, // Is this symbol a trampoline?
false, // Is this symbol artificial?
symbol_section, // Section in which this symbol is defined or null.
symbol_value, // Offset in section or symbol value.
symbol.st_size, // Size in bytes of this symbol.
flags); // Symbol flags.
i + start_id, // ID is the original symbol table index.
symbol_name, // Symbol name.
false, // Is the symbol name mangled?
symbol_type, // Type of this symbol
is_global, // Is this globally visible?
false, // Is this symbol debug info?
false, // Is this symbol a trampoline?
false, // Is this symbol artificial?
symbol_section_sp, // Section in which this symbol is defined or null.
symbol_value, // Offset in section or symbol value.
symbol.st_size, // Size in bytes of this symbol.
flags); // Symbol flags.
symtab->AddSymbol(dc_symbol);
}
@@ -929,7 +933,7 @@ ParsePLTRelocations(Symtab *symbol_table,
const ELFSectionHeader *rel_hdr,
const ELFSectionHeader *plt_hdr,
const ELFSectionHeader *sym_hdr,
Section *plt_section,
const lldb::SectionSP &plt_section_sp,
DataExtractor &rel_data,
DataExtractor &symtab_data,
DataExtractor &strtab_data)
@@ -982,7 +986,7 @@ ParsePLTRelocations(Symtab *symbol_table,
false, // Is this symbol debug info?
true, // Is this symbol a trampoline?
true, // Is this symbol artificial?
plt_section, // Section in which this symbol is defined or null.
plt_section_sp, // Section in which this symbol is defined or null.
plt_index, // Offset in section or symbol value.
plt_entsize, // Size in bytes of this symbol.
0); // Symbol flags.
@@ -1029,8 +1033,8 @@ ObjectFileELF::ParseTrampolineSymbols(Symtab *symbol_table,
if (!rel_section)
return 0;
Section *plt_section = section_list->FindSectionByID(plt_id).get();
if (!plt_section)
SectionSP plt_section_sp (section_list->FindSectionByID(plt_id));
if (!plt_section_sp)
return 0;
Section *symtab = section_list->FindSectionByID(symtab_id).get();
@@ -1057,10 +1061,17 @@ ObjectFileELF::ParseTrampolineSymbols(Symtab *symbol_table,
if (!rel_type)
return 0;
return ParsePLTRelocations(symbol_table, start_id, rel_type,
&m_header, rel_hdr, plt_hdr, sym_hdr,
plt_section,
rel_data, symtab_data, strtab_data);
return ParsePLTRelocations (symbol_table,
start_id,
rel_type,
&m_header,
rel_hdr,
plt_hdr,
sym_hdr,
plt_section_sp,
rel_data,
symtab_data,
strtab_data);
}
Symtab *