| //===-- DynamicLoaderHexagonDYLD.cpp ----------------------------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // C Includes |
| // C++ Includes |
| // Other libraries and framework includes |
| #include "lldb/Breakpoint/BreakpointLocation.h" |
| #include "lldb/Core/Module.h" |
| #include "lldb/Core/ModuleSpec.h" |
| #include "lldb/Core/PluginManager.h" |
| #include "lldb/Core/Section.h" |
| #include "lldb/Symbol/ObjectFile.h" |
| #include "lldb/Target/Process.h" |
| #include "lldb/Target/Target.h" |
| #include "lldb/Target/Thread.h" |
| #include "lldb/Target/ThreadPlanRunToAddress.h" |
| #include "lldb/Utility/Log.h" |
| |
| #include "DynamicLoaderHexagonDYLD.h" |
| |
| using namespace lldb; |
| using namespace lldb_private; |
| |
| // Aidan 21/05/2014 |
| // |
| // Notes about hexagon dynamic loading: |
| // |
| // When we connect to a target we find the dyld breakpoint address. We put |
| // a |
| // breakpoint there with a callback 'RendezvousBreakpointHit()'. |
| // |
| // It is possible to find the dyld structure address from the ELF symbol |
| // table, |
| // but in the case of the simulator it has not been initialized before the |
| // target calls dlinit(). |
| // |
| // We can only safely parse the dyld structure after we hit the dyld |
| // breakpoint |
| // since at that time we know dlinit() must have been called. |
| // |
| |
| // Find the load address of a symbol |
| static lldb::addr_t findSymbolAddress(Process *proc, ConstString findName) { |
| assert(proc != nullptr); |
| |
| ModuleSP module = proc->GetTarget().GetExecutableModule(); |
| assert(module.get() != nullptr); |
| |
| ObjectFile *exe = module->GetObjectFile(); |
| assert(exe != nullptr); |
| |
| lldb_private::Symtab *symtab = exe->GetSymtab(); |
| assert(symtab != nullptr); |
| |
| for (size_t i = 0; i < symtab->GetNumSymbols(); i++) { |
| const Symbol *sym = symtab->SymbolAtIndex(i); |
| assert(sym != nullptr); |
| const ConstString &symName = sym->GetName(); |
| |
| if (ConstString::Compare(findName, symName) == 0) { |
| Address addr = sym->GetAddress(); |
| return addr.GetLoadAddress(&proc->GetTarget()); |
| } |
| } |
| return LLDB_INVALID_ADDRESS; |
| } |
| |
| void DynamicLoaderHexagonDYLD::Initialize() { |
| PluginManager::RegisterPlugin(GetPluginNameStatic(), |
| GetPluginDescriptionStatic(), CreateInstance); |
| } |
| |
| void DynamicLoaderHexagonDYLD::Terminate() {} |
| |
| lldb_private::ConstString DynamicLoaderHexagonDYLD::GetPluginName() { |
| return GetPluginNameStatic(); |
| } |
| |
| lldb_private::ConstString DynamicLoaderHexagonDYLD::GetPluginNameStatic() { |
| static ConstString g_name("hexagon-dyld"); |
| return g_name; |
| } |
| |
| const char *DynamicLoaderHexagonDYLD::GetPluginDescriptionStatic() { |
| return "Dynamic loader plug-in that watches for shared library " |
| "loads/unloads in Hexagon processes."; |
| } |
| |
| uint32_t DynamicLoaderHexagonDYLD::GetPluginVersion() { return 1; } |
| |
| DynamicLoader *DynamicLoaderHexagonDYLD::CreateInstance(Process *process, |
| bool force) { |
| bool create = force; |
| if (!create) { |
| const llvm::Triple &triple_ref = |
| process->GetTarget().GetArchitecture().GetTriple(); |
| if (triple_ref.getArch() == llvm::Triple::hexagon) |
| create = true; |
| } |
| |
| if (create) |
| return new DynamicLoaderHexagonDYLD(process); |
| return NULL; |
| } |
| |
| DynamicLoaderHexagonDYLD::DynamicLoaderHexagonDYLD(Process *process) |
| : DynamicLoader(process), m_rendezvous(process), |
| m_load_offset(LLDB_INVALID_ADDRESS), m_entry_point(LLDB_INVALID_ADDRESS), |
| m_dyld_bid(LLDB_INVALID_BREAK_ID) {} |
| |
| DynamicLoaderHexagonDYLD::~DynamicLoaderHexagonDYLD() { |
| if (m_dyld_bid != LLDB_INVALID_BREAK_ID) { |
| m_process->GetTarget().RemoveBreakpointByID(m_dyld_bid); |
| m_dyld_bid = LLDB_INVALID_BREAK_ID; |
| } |
| } |
| |
| void DynamicLoaderHexagonDYLD::DidAttach() { |
| ModuleSP executable; |
| addr_t load_offset; |
| |
| executable = GetTargetExecutable(); |
| |
| // Find the difference between the desired load address in the elf file and |
| // the real load address in memory |
| load_offset = ComputeLoadOffset(); |
| |
| // Check that there is a valid executable |
| if (executable.get() == nullptr) |
| return; |
| |
| // Disable JIT for hexagon targets because its not supported |
| m_process->SetCanJIT(false); |
| |
| // Enable Interpreting of function call expressions |
| m_process->SetCanInterpretFunctionCalls(true); |
| |
| // Add the current executable to the module list |
| ModuleList module_list; |
| module_list.Append(executable); |
| |
| // Map the loaded sections of this executable |
| if (load_offset != LLDB_INVALID_ADDRESS) |
| UpdateLoadedSections(executable, LLDB_INVALID_ADDRESS, load_offset, true); |
| |
| // AD: confirm this? |
| // Load into LLDB all of the currently loaded executables in the stub |
| LoadAllCurrentModules(); |
| |
| // AD: confirm this? |
| // Callback for the target to give it the loaded module list |
| m_process->GetTarget().ModulesDidLoad(module_list); |
| |
| // Try to set a breakpoint at the rendezvous breakpoint. DidLaunch uses |
| // ProbeEntry() instead. That sets a breakpoint, at the dyld breakpoint |
| // address, with a callback so that when hit, the dyld structure can be |
| // parsed. |
| if (!SetRendezvousBreakpoint()) { |
| // fail |
| } |
| } |
| |
| void DynamicLoaderHexagonDYLD::DidLaunch() {} |
| |
| /// Checks to see if the target module has changed, updates the target |
| /// accordingly and returns the target executable module. |
| ModuleSP DynamicLoaderHexagonDYLD::GetTargetExecutable() { |
| Target &target = m_process->GetTarget(); |
| ModuleSP executable = target.GetExecutableModule(); |
| |
| // There is no executable |
| if (!executable.get()) |
| return executable; |
| |
| // The target executable file does not exits |
| if (!executable->GetFileSpec().Exists()) |
| return executable; |
| |
| // Prep module for loading |
| ModuleSpec module_spec(executable->GetFileSpec(), |
| executable->GetArchitecture()); |
| ModuleSP module_sp(new Module(module_spec)); |
| |
| // Check if the executable has changed and set it to the target executable if |
| // they differ. |
| if (module_sp.get() && module_sp->GetUUID().IsValid() && |
| executable->GetUUID().IsValid()) { |
| // if the executable has changed ?? |
| if (module_sp->GetUUID() != executable->GetUUID()) |
| executable.reset(); |
| } else if (executable->FileHasChanged()) |
| executable.reset(); |
| |
| if (executable.get()) |
| return executable; |
| |
| // TODO: What case is this code used? |
| executable = target.GetSharedModule(module_spec); |
| if (executable.get() != target.GetExecutableModulePointer()) { |
| // Don't load dependent images since we are in dyld where we will know and |
| // find out about all images that are loaded |
| const bool get_dependent_images = false; |
| target.SetExecutableModule(executable, get_dependent_images); |
| } |
| |
| return executable; |
| } |
| |
| // AD: Needs to be updated? |
| Status DynamicLoaderHexagonDYLD::CanLoadImage() { return Status(); } |
| |
| void DynamicLoaderHexagonDYLD::UpdateLoadedSections(ModuleSP module, |
| addr_t link_map_addr, |
| addr_t base_addr, |
| bool base_addr_is_offset) { |
| Target &target = m_process->GetTarget(); |
| const SectionList *sections = GetSectionListFromModule(module); |
| |
| assert(sections && "SectionList missing from loaded module."); |
| |
| m_loaded_modules[module] = link_map_addr; |
| |
| const size_t num_sections = sections->GetSize(); |
| |
| for (unsigned i = 0; i < num_sections; ++i) { |
| SectionSP section_sp(sections->GetSectionAtIndex(i)); |
| lldb::addr_t new_load_addr = section_sp->GetFileAddress() + base_addr; |
| |
| // AD: 02/05/14 |
| // since our memory map starts from address 0, we must not ignore |
| // sections that load to address 0. This violates the reference |
| // ELF spec, however is used for Hexagon. |
| |
| // If the file address of the section is zero then this is not an |
| // allocatable/loadable section (property of ELF sh_addr). Skip it. |
| // if (new_load_addr == base_addr) |
| // continue; |
| |
| target.SetSectionLoadAddress(section_sp, new_load_addr); |
| } |
| } |
| |
| /// Removes the loaded sections from the target in @p module. |
| /// |
| /// @param module The module to traverse. |
| void DynamicLoaderHexagonDYLD::UnloadSections(const ModuleSP module) { |
| Target &target = m_process->GetTarget(); |
| const SectionList *sections = GetSectionListFromModule(module); |
| |
| assert(sections && "SectionList missing from unloaded module."); |
| |
| m_loaded_modules.erase(module); |
| |
| const size_t num_sections = sections->GetSize(); |
| for (size_t i = 0; i < num_sections; ++i) { |
| SectionSP section_sp(sections->GetSectionAtIndex(i)); |
| target.SetSectionUnloaded(section_sp); |
| } |
| } |
| |
| // Place a breakpoint on <_rtld_debug_state> |
| bool DynamicLoaderHexagonDYLD::SetRendezvousBreakpoint() { |
| Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER)); |
| |
| // This is the original code, which want to look in the rendezvous structure |
| // to find the breakpoint address. Its backwards for us, since we can easily |
| // find the breakpoint address, since it is exported in our executable. We |
| // however know that we cant read the Rendezvous structure until we have hit |
| // the breakpoint once. |
| const ConstString dyldBpName("_rtld_debug_state"); |
| addr_t break_addr = findSymbolAddress(m_process, dyldBpName); |
| |
| Target &target = m_process->GetTarget(); |
| |
| // Do not try to set the breakpoint if we don't know where to put it |
| if (break_addr == LLDB_INVALID_ADDRESS) { |
| if (log) |
| log->Printf("Unable to locate _rtld_debug_state breakpoint address"); |
| |
| return false; |
| } |
| |
| // Save the address of the rendezvous structure |
| m_rendezvous.SetBreakAddress(break_addr); |
| |
| // If we haven't set the breakpoint before then set it |
| if (m_dyld_bid == LLDB_INVALID_BREAK_ID) { |
| Breakpoint *dyld_break = |
| target.CreateBreakpoint(break_addr, true, false).get(); |
| dyld_break->SetCallback(RendezvousBreakpointHit, this, true); |
| dyld_break->SetBreakpointKind("shared-library-event"); |
| m_dyld_bid = dyld_break->GetID(); |
| |
| // Make sure our breakpoint is at the right address. |
| assert(target.GetBreakpointByID(m_dyld_bid) |
| ->FindLocationByAddress(break_addr) |
| ->GetBreakpoint() |
| .GetID() == m_dyld_bid); |
| |
| if (log && dyld_break == nullptr) |
| log->Printf("Failed to create _rtld_debug_state breakpoint"); |
| |
| // check we have successfully set bp |
| return (dyld_break != nullptr); |
| } else |
| // rendezvous already set |
| return true; |
| } |
| |
| // We have just hit our breakpoint at <_rtld_debug_state> |
| bool DynamicLoaderHexagonDYLD::RendezvousBreakpointHit( |
| void *baton, StoppointCallbackContext *context, user_id_t break_id, |
| user_id_t break_loc_id) { |
| Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER)); |
| |
| if (log) |
| log->Printf("Rendezvous breakpoint hit!"); |
| |
| DynamicLoaderHexagonDYLD *dyld_instance = nullptr; |
| dyld_instance = static_cast<DynamicLoaderHexagonDYLD *>(baton); |
| |
| // if the dyld_instance is still not valid then try to locate it on the |
| // symbol table |
| if (!dyld_instance->m_rendezvous.IsValid()) { |
| Process *proc = dyld_instance->m_process; |
| |
| const ConstString dyldStructName("_rtld_debug"); |
| addr_t structAddr = findSymbolAddress(proc, dyldStructName); |
| |
| if (structAddr != LLDB_INVALID_ADDRESS) { |
| dyld_instance->m_rendezvous.SetRendezvousAddress(structAddr); |
| |
| if (log) |
| log->Printf("Found _rtld_debug structure @ 0x%08" PRIx64, structAddr); |
| } else { |
| if (log) |
| log->Printf("Unable to resolve the _rtld_debug structure"); |
| } |
| } |
| |
| dyld_instance->RefreshModules(); |
| |
| // Return true to stop the target, false to just let the target run. |
| return dyld_instance->GetStopWhenImagesChange(); |
| } |
| |
| /// Helper method for RendezvousBreakpointHit. Updates LLDB's current set |
| /// of loaded modules. |
| void DynamicLoaderHexagonDYLD::RefreshModules() { |
| Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER)); |
| |
| if (!m_rendezvous.Resolve()) |
| return; |
| |
| HexagonDYLDRendezvous::iterator I; |
| HexagonDYLDRendezvous::iterator E; |
| |
| ModuleList &loaded_modules = m_process->GetTarget().GetImages(); |
| |
| if (m_rendezvous.ModulesDidLoad()) { |
| ModuleList new_modules; |
| |
| E = m_rendezvous.loaded_end(); |
| for (I = m_rendezvous.loaded_begin(); I != E; ++I) { |
| FileSpec file(I->path, true); |
| ModuleSP module_sp = |
| LoadModuleAtAddress(file, I->link_addr, I->base_addr, true); |
| if (module_sp.get()) { |
| loaded_modules.AppendIfNeeded(module_sp); |
| new_modules.Append(module_sp); |
| } |
| |
| if (log) { |
| log->Printf("Target is loading '%s'", I->path.c_str()); |
| if (!module_sp.get()) |
| log->Printf("LLDB failed to load '%s'", I->path.c_str()); |
| else |
| log->Printf("LLDB successfully loaded '%s'", I->path.c_str()); |
| } |
| } |
| m_process->GetTarget().ModulesDidLoad(new_modules); |
| } |
| |
| if (m_rendezvous.ModulesDidUnload()) { |
| ModuleList old_modules; |
| |
| E = m_rendezvous.unloaded_end(); |
| for (I = m_rendezvous.unloaded_begin(); I != E; ++I) { |
| FileSpec file(I->path, true); |
| ModuleSpec module_spec(file); |
| ModuleSP module_sp = loaded_modules.FindFirstModule(module_spec); |
| |
| if (module_sp.get()) { |
| old_modules.Append(module_sp); |
| UnloadSections(module_sp); |
| } |
| |
| if (log) |
| log->Printf("Target is unloading '%s'", I->path.c_str()); |
| } |
| loaded_modules.Remove(old_modules); |
| m_process->GetTarget().ModulesDidUnload(old_modules, false); |
| } |
| } |
| |
| // AD: This is very different to the Static Loader code. |
| // It may be wise to look over this and its relation to stack |
| // unwinding. |
| ThreadPlanSP |
| DynamicLoaderHexagonDYLD::GetStepThroughTrampolinePlan(Thread &thread, |
| bool stop) { |
| ThreadPlanSP thread_plan_sp; |
| |
| StackFrame *frame = thread.GetStackFrameAtIndex(0).get(); |
| const SymbolContext &context = frame->GetSymbolContext(eSymbolContextSymbol); |
| Symbol *sym = context.symbol; |
| |
| if (sym == NULL || !sym->IsTrampoline()) |
| return thread_plan_sp; |
| |
| const ConstString sym_name = sym->GetMangled().GetName( |
| lldb::eLanguageTypeUnknown, Mangled::ePreferMangled); |
| if (!sym_name) |
| return thread_plan_sp; |
| |
| SymbolContextList target_symbols; |
| Target &target = thread.GetProcess()->GetTarget(); |
| const ModuleList &images = target.GetImages(); |
| |
| images.FindSymbolsWithNameAndType(sym_name, eSymbolTypeCode, target_symbols); |
| size_t num_targets = target_symbols.GetSize(); |
| if (!num_targets) |
| return thread_plan_sp; |
| |
| typedef std::vector<lldb::addr_t> AddressVector; |
| AddressVector addrs; |
| for (size_t i = 0; i < num_targets; ++i) { |
| SymbolContext context; |
| AddressRange range; |
| if (target_symbols.GetContextAtIndex(i, context)) { |
| context.GetAddressRange(eSymbolContextEverything, 0, false, range); |
| lldb::addr_t addr = range.GetBaseAddress().GetLoadAddress(&target); |
| if (addr != LLDB_INVALID_ADDRESS) |
| addrs.push_back(addr); |
| } |
| } |
| |
| if (addrs.size() > 0) { |
| AddressVector::iterator start = addrs.begin(); |
| AddressVector::iterator end = addrs.end(); |
| |
| std::sort(start, end); |
| addrs.erase(std::unique(start, end), end); |
| thread_plan_sp.reset(new ThreadPlanRunToAddress(thread, addrs, stop)); |
| } |
| |
| return thread_plan_sp; |
| } |
| |
| /// Helper for the entry breakpoint callback. Resolves the load addresses |
| /// of all dependent modules. |
| void DynamicLoaderHexagonDYLD::LoadAllCurrentModules() { |
| HexagonDYLDRendezvous::iterator I; |
| HexagonDYLDRendezvous::iterator E; |
| ModuleList module_list; |
| |
| if (!m_rendezvous.Resolve()) { |
| Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER)); |
| if (log) |
| log->Printf( |
| "DynamicLoaderHexagonDYLD::%s unable to resolve rendezvous address", |
| __FUNCTION__); |
| return; |
| } |
| |
| // The rendezvous class doesn't enumerate the main module, so track that |
| // ourselves here. |
| ModuleSP executable = GetTargetExecutable(); |
| m_loaded_modules[executable] = m_rendezvous.GetLinkMapAddress(); |
| |
| for (I = m_rendezvous.begin(), E = m_rendezvous.end(); I != E; ++I) { |
| const char *module_path = I->path.c_str(); |
| FileSpec file(module_path, false); |
| ModuleSP module_sp = |
| LoadModuleAtAddress(file, I->link_addr, I->base_addr, true); |
| if (module_sp.get()) { |
| module_list.Append(module_sp); |
| } else { |
| Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER)); |
| if (log) |
| log->Printf("DynamicLoaderHexagonDYLD::%s failed loading module %s at " |
| "0x%" PRIx64, |
| __FUNCTION__, module_path, I->base_addr); |
| } |
| } |
| |
| m_process->GetTarget().ModulesDidLoad(module_list); |
| } |
| |
| /// Computes a value for m_load_offset returning the computed address on |
| /// success and LLDB_INVALID_ADDRESS on failure. |
| addr_t DynamicLoaderHexagonDYLD::ComputeLoadOffset() { |
| // Here we could send a GDB packet to know the load offset |
| // |
| // send: $qOffsets#4b |
| // get: Text=0;Data=0;Bss=0 |
| // |
| // Currently qOffsets is not supported by pluginProcessGDBRemote |
| // |
| return 0; |
| } |
| |
| // Here we must try to read the entry point directly from the elf header. This |
| // is possible if the process is not relocatable or dynamically linked. |
| // |
| // an alternative is to look at the PC if we can be sure that we have connected |
| // when the process is at the entry point. |
| // I dont think that is reliable for us. |
| addr_t DynamicLoaderHexagonDYLD::GetEntryPoint() { |
| if (m_entry_point != LLDB_INVALID_ADDRESS) |
| return m_entry_point; |
| // check we have a valid process |
| if (m_process == nullptr) |
| return LLDB_INVALID_ADDRESS; |
| // Get the current executable module |
| Module &module = *(m_process->GetTarget().GetExecutableModule().get()); |
| // Get the object file (elf file) for this module |
| lldb_private::ObjectFile &object = *(module.GetObjectFile()); |
| // Check if the file is executable (ie, not shared object or relocatable) |
| if (object.IsExecutable()) { |
| // Get the entry point address for this object |
| lldb_private::Address entry = object.GetEntryPointAddress(); |
| // Return the entry point address |
| return entry.GetFileAddress(); |
| } |
| // No idea so back out |
| return LLDB_INVALID_ADDRESS; |
| } |
| |
| const SectionList *DynamicLoaderHexagonDYLD::GetSectionListFromModule( |
| const ModuleSP module) const { |
| SectionList *sections = nullptr; |
| if (module.get()) { |
| ObjectFile *obj_file = module->GetObjectFile(); |
| if (obj_file) { |
| sections = obj_file->GetSectionList(); |
| } |
| } |
| return sections; |
| } |
| |
| static int ReadInt(Process *process, addr_t addr) { |
| Status error; |
| int value = (int)process->ReadUnsignedIntegerFromMemory( |
| addr, sizeof(uint32_t), 0, error); |
| if (error.Fail()) |
| return -1; |
| else |
| return value; |
| } |
| |
| lldb::addr_t |
| DynamicLoaderHexagonDYLD::GetThreadLocalData(const lldb::ModuleSP module, |
| const lldb::ThreadSP thread, |
| lldb::addr_t tls_file_addr) { |
| auto it = m_loaded_modules.find(module); |
| if (it == m_loaded_modules.end()) |
| return LLDB_INVALID_ADDRESS; |
| |
| addr_t link_map = it->second; |
| if (link_map == LLDB_INVALID_ADDRESS) |
| return LLDB_INVALID_ADDRESS; |
| |
| const HexagonDYLDRendezvous::ThreadInfo &metadata = |
| m_rendezvous.GetThreadInfo(); |
| if (!metadata.valid) |
| return LLDB_INVALID_ADDRESS; |
| |
| // Get the thread pointer. |
| addr_t tp = thread->GetThreadPointer(); |
| if (tp == LLDB_INVALID_ADDRESS) |
| return LLDB_INVALID_ADDRESS; |
| |
| // Find the module's modid. |
| int modid = ReadInt(m_process, link_map + metadata.modid_offset); |
| if (modid == -1) |
| return LLDB_INVALID_ADDRESS; |
| |
| // Lookup the DTV structure for this thread. |
| addr_t dtv_ptr = tp + metadata.dtv_offset; |
| addr_t dtv = ReadPointer(dtv_ptr); |
| if (dtv == LLDB_INVALID_ADDRESS) |
| return LLDB_INVALID_ADDRESS; |
| |
| // Find the TLS block for this module. |
| addr_t dtv_slot = dtv + metadata.dtv_slot_size * modid; |
| addr_t tls_block = ReadPointer(dtv_slot + metadata.tls_offset); |
| |
| Module *mod = module.get(); |
| Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER)); |
| if (log) |
| log->Printf("DynamicLoaderHexagonDYLD::Performed TLS lookup: " |
| "module=%s, link_map=0x%" PRIx64 ", tp=0x%" PRIx64 |
| ", modid=%i, tls_block=0x%" PRIx64, |
| mod->GetObjectName().AsCString(""), link_map, tp, modid, |
| tls_block); |
| |
| if (tls_block == LLDB_INVALID_ADDRESS) |
| return LLDB_INVALID_ADDRESS; |
| else |
| return tls_block + tls_file_addr; |
| } |