Skip to content

[lldb] Change Module to have a concrete UnwindTable, update (#101130) #9121

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Aug 27, 2024
Merged

[lldb] Change Module to have a concrete UnwindTable, update (#101130) #9121

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
6 changes: 3 additions & 3 deletions lldb/include/lldb/Core/Module.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1041,9 +1041,9 @@ class Module : public std::enable_shared_from_this<Module>,
lldb::ObjectFileSP m_objfile_sp; ///< A shared pointer to the object file
/// parser for this module as it may or may
/// not be shared with the SymbolFile
std::optional<UnwindTable> m_unwind_table; ///< Table of FuncUnwinders
/// objects created for this
/// Module's functions
UnwindTable m_unwind_table; ///< Table of FuncUnwinders
/// objects created for this
/// Module's functions
lldb::SymbolVendorUP
m_symfile_up; ///< A pointer to the symbol vendor for this module.
std::vector<lldb::SymbolVendorUP>
Expand Down
12 changes: 8 additions & 4 deletions lldb/include/lldb/Symbol/UnwindTable.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -57,9 +57,9 @@ class UnwindTable {

ArchSpec GetArchitecture();

/// Called after a SymbolFile has been added to a Module to add any new
/// unwind sections that may now be available.
void Update();
/// Called after an ObjectFile/SymbolFile has been added to a Module to add
/// any new unwind sections that may now be available.
void ModuleWasUpdated();

private:
void Dump(Stream &s);
Expand All @@ -75,7 +75,11 @@ class UnwindTable {
Module &m_module;
collection m_unwinds;

bool m_initialized; // delay some initialization until ObjectFile is set up
bool m_scanned_all_unwind_sources; // true when we have looked at the
// ObjectFile and SymbolFile for all
// sources of unwind information; false if
// we haven't done that yet, or one of the
// files has been updated in the Module.
std::mutex m_mutex;

std::unique_ptr<CallFrameInfo> m_object_file_unwind_up;
Expand Down
27 changes: 15 additions & 12 deletions lldb/source/Core/Module.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -136,7 +136,8 @@ Module *Module::GetAllocatedModuleAtIndex(size_t idx) {
}

Module::Module(const ModuleSpec &module_spec)
: m_file_has_changed(false), m_first_file_changed_log(false) {
: m_unwind_table(*this), m_file_has_changed(false),
m_first_file_changed_log(false) {
// Scope for locker below...
{
std::lock_guard<std::recursive_mutex> guard(
Expand Down Expand Up @@ -242,8 +243,8 @@ Module::Module(const FileSpec &file_spec, const ArchSpec &arch,
const llvm::sys::TimePoint<> &object_mod_time)
: m_mod_time(FileSystem::Instance().GetModificationTime(file_spec)),
m_arch(arch), m_file(file_spec), m_object_offset(object_offset),
m_object_mod_time(object_mod_time), m_file_has_changed(false),
m_first_file_changed_log(false) {
m_object_mod_time(object_mod_time), m_unwind_table(*this),
m_file_has_changed(false), m_first_file_changed_log(false) {
// Scope for locker below...
{
std::lock_guard<std::recursive_mutex> guard(
Expand All @@ -262,7 +263,9 @@ Module::Module(const FileSpec &file_spec, const ArchSpec &arch,
m_object_name.AsCString(""), m_object_name.IsEmpty() ? "" : ")");
}

Module::Module() : m_file_has_changed(false), m_first_file_changed_log(false) {
Module::Module()
: m_unwind_table(*this), m_file_has_changed(false),
m_first_file_changed_log(false) {
std::lock_guard<std::recursive_mutex> guard(
GetAllocationModuleCollectionMutex());
GetModuleCollection().push_back(this);
Expand Down Expand Up @@ -331,6 +334,8 @@ ObjectFile *Module::GetMemoryObjectFile(const lldb::ProcessSP &process_sp,
// Augment the arch with the target's information in case
// we are unable to extract the os/environment from memory.
m_arch.MergeFrom(process_sp->GetTarget().GetArchitecture());

m_unwind_table.ModuleWasUpdated();
} else {
error.SetErrorString("unable to find suitable object file plug-in");
}
Expand Down Expand Up @@ -1046,8 +1051,7 @@ SymbolFile *Module::GetSymbolFile(bool can_create, Stream *feedback_strm) {
m_symfile_up.reset(
SymbolVendor::FindPlugin(shared_from_this(), feedback_strm));
m_did_load_symfile = true;
if (m_unwind_table)
m_unwind_table->Update();
m_unwind_table.ModuleWasUpdated();
}
}
}
Expand Down Expand Up @@ -1345,6 +1349,8 @@ ObjectFile *Module::GetObjectFile() {
// more specific than the generic COFF architecture, only merge in
// those values that overwrite unspecified unknown values.
m_arch.MergeFrom(m_objfile_sp->GetArchitecture());

m_unwind_table.ModuleWasUpdated();
} else {
ReportError("failed to load objfile for {0}",
GetFileSpec().GetPath().c_str());
Expand Down Expand Up @@ -1374,12 +1380,9 @@ void Module::SectionFileAddressesChanged() {
}

UnwindTable &Module::GetUnwindTable() {
if (!m_unwind_table) {
if (!m_symfile_spec)
SymbolLocator::DownloadSymbolFileAsync(GetUUID());
m_unwind_table.emplace(*this);
}
return *m_unwind_table;
if (!m_symfile_spec)
SymbolLocator::DownloadSymbolFileAsync(GetUUID());
return m_unwind_table;
}

SectionList *Module::GetUnifiedSectionList() {
Expand Down
71 changes: 15 additions & 56 deletions lldb/source/Symbol/UnwindTable.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -30,70 +30,27 @@ using namespace lldb;
using namespace lldb_private;

UnwindTable::UnwindTable(Module &module)
: m_module(module), m_unwinds(), m_initialized(false), m_mutex(),
m_object_file_unwind_up(), m_eh_frame_up(), m_compact_unwind_up(),
m_arm_unwind_up() {}
: m_module(module), m_unwinds(), m_scanned_all_unwind_sources(false),
m_mutex(), m_object_file_unwind_up(), m_eh_frame_up(),
m_compact_unwind_up(), m_arm_unwind_up() {}

// We can't do some of this initialization when the ObjectFile is running its
// ctor; delay doing it until needed for something.

void UnwindTable::Initialize() {
if (m_initialized)
if (m_scanned_all_unwind_sources)
return;

std::lock_guard<std::mutex> guard(m_mutex);

if (m_initialized) // check again once we've acquired the lock
return;
m_initialized = true;
ObjectFile *object_file = m_module.GetObjectFile();
if (!object_file)
if (m_scanned_all_unwind_sources) // check again once we've acquired the lock
return;

m_object_file_unwind_up = object_file->CreateCallFrameInfo();

SectionList *sl = m_module.GetSectionList();
if (!sl)
return;

SectionSP sect = sl->FindSectionByType(eSectionTypeEHFrame, true);
if (sect.get()) {
m_eh_frame_up = std::make_unique<DWARFCallFrameInfo>(
*object_file, sect, DWARFCallFrameInfo::EH);
}

sect = sl->FindSectionByType(eSectionTypeDWARFDebugFrame, true);
if (sect) {
m_debug_frame_up = std::make_unique<DWARFCallFrameInfo>(
*object_file, sect, DWARFCallFrameInfo::DWARF);
}

sect = sl->FindSectionByType(eSectionTypeCompactUnwind, true);
if (sect) {
m_compact_unwind_up =
std::make_unique<CompactUnwindInfo>(*object_file, sect);
}

sect = sl->FindSectionByType(eSectionTypeARMexidx, true);
if (sect) {
SectionSP sect_extab = sl->FindSectionByType(eSectionTypeARMextab, true);
if (sect_extab.get()) {
m_arm_unwind_up =
std::make_unique<ArmUnwindInfo>(*object_file, sect, sect_extab);
}
}
}

void UnwindTable::Update() {
if (!m_initialized)
return Initialize();

std::lock_guard<std::mutex> guard(m_mutex);

ObjectFile *object_file = m_module.GetObjectFile();
if (!object_file)
return;

m_scanned_all_unwind_sources = true;

if (!m_object_file_unwind_up)
m_object_file_unwind_up = object_file->CreateCallFrameInfo();

Expand All @@ -102,22 +59,19 @@ void UnwindTable::Update() {
return;

SectionSP sect = sl->FindSectionByType(eSectionTypeEHFrame, true);
if (!m_eh_frame_up && sect) {
if (!m_eh_frame_up && sect)
m_eh_frame_up = std::make_unique<DWARFCallFrameInfo>(
*object_file, sect, DWARFCallFrameInfo::EH);
}

sect = sl->FindSectionByType(eSectionTypeDWARFDebugFrame, true);
if (!m_debug_frame_up && sect) {
if (!m_debug_frame_up && sect)
m_debug_frame_up = std::make_unique<DWARFCallFrameInfo>(
*object_file, sect, DWARFCallFrameInfo::DWARF);
}

sect = sl->FindSectionByType(eSectionTypeCompactUnwind, true);
if (!m_compact_unwind_up && sect) {
if (!m_compact_unwind_up && sect)
m_compact_unwind_up =
std::make_unique<CompactUnwindInfo>(*object_file, sect);
}

sect = sl->FindSectionByType(eSectionTypeARMexidx, true);
if (!m_arm_unwind_up && sect) {
Expand All @@ -129,6 +83,11 @@ void UnwindTable::Update() {
}
}

void UnwindTable::ModuleWasUpdated() {
std::lock_guard<std::mutex> guard(m_mutex);
m_scanned_all_unwind_sources = false;
}

UnwindTable::~UnwindTable() = default;

std::optional<AddressRange>
Expand Down