diff options
Diffstat (limited to 'gnu/llvm/lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp')
| -rw-r--r-- | gnu/llvm/lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp | 616 |
1 files changed, 616 insertions, 0 deletions
diff --git a/gnu/llvm/lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp b/gnu/llvm/lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp new file mode 100644 index 00000000000..9efb021caa8 --- /dev/null +++ b/gnu/llvm/lldb/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp @@ -0,0 +1,616 @@ +//===-- ItaniumABILanguageRuntime.cpp --------------------------------------*- +//C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#include "ItaniumABILanguageRuntime.h" + +#include "lldb/Breakpoint/BreakpointLocation.h" +#include "lldb/Core/Mangled.h" +#include "lldb/Core/Module.h" +#include "lldb/Core/PluginManager.h" +#include "lldb/Core/ValueObject.h" +#include "lldb/Core/ValueObjectMemory.h" +#include "lldb/DataFormatters/FormattersHelpers.h" +#include "lldb/Expression/DiagnosticManager.h" +#include "lldb/Expression/FunctionCaller.h" +#include "lldb/Interpreter/CommandObject.h" +#include "lldb/Interpreter/CommandObjectMultiword.h" +#include "lldb/Interpreter/CommandReturnObject.h" +#include "lldb/Symbol/ClangASTContext.h" +#include "lldb/Symbol/Symbol.h" +#include "lldb/Symbol/SymbolFile.h" +#include "lldb/Symbol/TypeList.h" +#include "lldb/Target/Process.h" +#include "lldb/Target/RegisterContext.h" +#include "lldb/Target/SectionLoadList.h" +#include "lldb/Target/StopInfo.h" +#include "lldb/Target/Target.h" +#include "lldb/Target/Thread.h" +#include "lldb/Utility/ConstString.h" +#include "lldb/Utility/Log.h" +#include "lldb/Utility/Scalar.h" +#include "lldb/Utility/Status.h" + +#include <vector> + +using namespace lldb; +using namespace lldb_private; + +static const char *vtable_demangled_prefix = "vtable for "; + +char ItaniumABILanguageRuntime::ID = 0; + +bool ItaniumABILanguageRuntime::CouldHaveDynamicValue(ValueObject &in_value) { + const bool check_cxx = true; + const bool check_objc = false; + return in_value.GetCompilerType().IsPossibleDynamicType(nullptr, check_cxx, + check_objc); +} + +TypeAndOrName ItaniumABILanguageRuntime::GetTypeInfoFromVTableAddress( + ValueObject &in_value, lldb::addr_t original_ptr, + lldb::addr_t vtable_load_addr) { + if (m_process && vtable_load_addr != LLDB_INVALID_ADDRESS) { + // Find the symbol that contains the "vtable_load_addr" address + Address vtable_addr; + Target &target = m_process->GetTarget(); + if (!target.GetSectionLoadList().IsEmpty()) { + if (target.GetSectionLoadList().ResolveLoadAddress(vtable_load_addr, + vtable_addr)) { + // See if we have cached info for this type already + TypeAndOrName type_info = GetDynamicTypeInfo(vtable_addr); + if (type_info) + return type_info; + + SymbolContext sc; + target.GetImages().ResolveSymbolContextForAddress( + vtable_addr, eSymbolContextSymbol, sc); + Symbol *symbol = sc.symbol; + if (symbol != nullptr) { + const char *name = + symbol->GetMangled() + .GetDemangledName(lldb::eLanguageTypeC_plus_plus) + .AsCString(); + if (name && strstr(name, vtable_demangled_prefix) == name) { + Log *log( + lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_OBJECT)); + LLDB_LOGF(log, + "0x%16.16" PRIx64 + ": static-type = '%s' has vtable symbol '%s'\n", + original_ptr, in_value.GetTypeName().GetCString(), name); + // We are a C++ class, that's good. Get the class name and look it + // up: + const char *class_name = name + strlen(vtable_demangled_prefix); + // We know the class name is absolute, so tell FindTypes that by + // prefixing it with the root namespace: + std::string lookup_name("::"); + lookup_name.append(class_name); + + type_info.SetName(class_name); + const bool exact_match = true; + TypeList class_types; + + // First look in the module that the vtable symbol came from and + // look for a single exact match. + llvm::DenseSet<SymbolFile *> searched_symbol_files; + if (sc.module_sp) + sc.module_sp->FindTypes(ConstString(lookup_name), exact_match, 1, + searched_symbol_files, class_types); + + // If we didn't find a symbol, then move on to the entire module + // list in the target and get as many unique matches as possible + if (class_types.Empty()) + target.GetImages().FindTypes(nullptr, ConstString(lookup_name), + exact_match, UINT32_MAX, + searched_symbol_files, class_types); + + lldb::TypeSP type_sp; + if (class_types.Empty()) { + LLDB_LOGF(log, "0x%16.16" PRIx64 ": is not dynamic\n", + original_ptr); + return TypeAndOrName(); + } + if (class_types.GetSize() == 1) { + type_sp = class_types.GetTypeAtIndex(0); + if (type_sp) { + if (ClangASTContext::IsCXXClassType( + type_sp->GetForwardCompilerType())) { + LLDB_LOGF( + log, + "0x%16.16" PRIx64 + ": static-type = '%s' has dynamic type: uid={0x%" PRIx64 + "}, type-name='%s'\n", + original_ptr, in_value.GetTypeName().AsCString(), + type_sp->GetID(), type_sp->GetName().GetCString()); + type_info.SetTypeSP(type_sp); + } + } + } else { + size_t i; + if (log) { + for (i = 0; i < class_types.GetSize(); i++) { + type_sp = class_types.GetTypeAtIndex(i); + if (type_sp) { + LLDB_LOGF( + log, + "0x%16.16" PRIx64 + ": static-type = '%s' has multiple matching dynamic " + "types: uid={0x%" PRIx64 "}, type-name='%s'\n", + original_ptr, in_value.GetTypeName().AsCString(), + type_sp->GetID(), type_sp->GetName().GetCString()); + } + } + } + + for (i = 0; i < class_types.GetSize(); i++) { + type_sp = class_types.GetTypeAtIndex(i); + if (type_sp) { + if (ClangASTContext::IsCXXClassType( + type_sp->GetForwardCompilerType())) { + LLDB_LOGF( + log, + "0x%16.16" PRIx64 ": static-type = '%s' has multiple " + "matching dynamic types, picking " + "this one: uid={0x%" PRIx64 "}, type-name='%s'\n", + original_ptr, in_value.GetTypeName().AsCString(), + type_sp->GetID(), type_sp->GetName().GetCString()); + type_info.SetTypeSP(type_sp); + } + } + } + + if (log) { + LLDB_LOGF(log, + "0x%16.16" PRIx64 + ": static-type = '%s' has multiple matching dynamic " + "types, didn't find a C++ match\n", + original_ptr, in_value.GetTypeName().AsCString()); + } + } + if (type_info) + SetDynamicTypeInfo(vtable_addr, type_info); + return type_info; + } + } + } + } + } + return TypeAndOrName(); +} + +bool ItaniumABILanguageRuntime::GetDynamicTypeAndAddress( + ValueObject &in_value, lldb::DynamicValueType use_dynamic, + TypeAndOrName &class_type_or_name, Address &dynamic_address, + Value::ValueType &value_type) { + // For Itanium, if the type has a vtable pointer in the object, it will be at + // offset 0 in the object. That will point to the "address point" within the + // vtable (not the beginning of the vtable.) We can then look up the symbol + // containing this "address point" and that symbol's name demangled will + // contain the full class name. The second pointer above the "address point" + // is the "offset_to_top". We'll use that to get the start of the value + // object which holds the dynamic type. + // + + class_type_or_name.Clear(); + value_type = Value::ValueType::eValueTypeScalar; + + // Only a pointer or reference type can have a different dynamic and static + // type: + if (!CouldHaveDynamicValue(in_value)) + return false; + + // First job, pull out the address at 0 offset from the object. + AddressType address_type; + lldb::addr_t original_ptr = in_value.GetPointerValue(&address_type); + if (original_ptr == LLDB_INVALID_ADDRESS) + return false; + + ExecutionContext exe_ctx(in_value.GetExecutionContextRef()); + + Process *process = exe_ctx.GetProcessPtr(); + + if (process == nullptr) + return false; + + Status error; + const lldb::addr_t vtable_address_point = + process->ReadPointerFromMemory(original_ptr, error); + + if (!error.Success() || vtable_address_point == LLDB_INVALID_ADDRESS) + return false; + + class_type_or_name = GetTypeInfoFromVTableAddress(in_value, original_ptr, + vtable_address_point); + + if (!class_type_or_name) + return false; + + CompilerType type = class_type_or_name.GetCompilerType(); + // There can only be one type with a given name, so we've just found + // duplicate definitions, and this one will do as well as any other. We + // don't consider something to have a dynamic type if it is the same as + // the static type. So compare against the value we were handed. + if (!type) + return true; + + if (ClangASTContext::AreTypesSame(in_value.GetCompilerType(), type)) { + // The dynamic type we found was the same type, so we don't have a + // dynamic type here... + return false; + } + + // The offset_to_top is two pointers above the vtable pointer. + const uint32_t addr_byte_size = process->GetAddressByteSize(); + const lldb::addr_t offset_to_top_location = + vtable_address_point - 2 * addr_byte_size; + // Watch for underflow, offset_to_top_location should be less than + // vtable_address_point + if (offset_to_top_location >= vtable_address_point) + return false; + const int64_t offset_to_top = process->ReadSignedIntegerFromMemory( + offset_to_top_location, addr_byte_size, INT64_MIN, error); + + if (offset_to_top == INT64_MIN) + return false; + // So the dynamic type is a value that starts at offset_to_top above + // the original address. + lldb::addr_t dynamic_addr = original_ptr + offset_to_top; + if (!process->GetTarget().GetSectionLoadList().ResolveLoadAddress( + dynamic_addr, dynamic_address)) { + dynamic_address.SetRawAddress(dynamic_addr); + } + return true; +} + +TypeAndOrName ItaniumABILanguageRuntime::FixUpDynamicType( + const TypeAndOrName &type_and_or_name, ValueObject &static_value) { + CompilerType static_type(static_value.GetCompilerType()); + Flags static_type_flags(static_type.GetTypeInfo()); + + TypeAndOrName ret(type_and_or_name); + if (type_and_or_name.HasType()) { + // The type will always be the type of the dynamic object. If our parent's + // type was a pointer, then our type should be a pointer to the type of the + // dynamic object. If a reference, then the original type should be + // okay... + CompilerType orig_type = type_and_or_name.GetCompilerType(); + CompilerType corrected_type = orig_type; + if (static_type_flags.AllSet(eTypeIsPointer)) + corrected_type = orig_type.GetPointerType(); + else if (static_type_flags.AllSet(eTypeIsReference)) + corrected_type = orig_type.GetLValueReferenceType(); + ret.SetCompilerType(corrected_type); + } else { + // If we are here we need to adjust our dynamic type name to include the + // correct & or * symbol + std::string corrected_name(type_and_or_name.GetName().GetCString()); + if (static_type_flags.AllSet(eTypeIsPointer)) + corrected_name.append(" *"); + else if (static_type_flags.AllSet(eTypeIsReference)) + corrected_name.append(" &"); + // the parent type should be a correctly pointer'ed or referenc'ed type + ret.SetCompilerType(static_type); + ret.SetName(corrected_name.c_str()); + } + return ret; +} + +// Static Functions +LanguageRuntime * +ItaniumABILanguageRuntime::CreateInstance(Process *process, + lldb::LanguageType language) { + // FIXME: We have to check the process and make sure we actually know that + // this process supports + // the Itanium ABI. + if (language == eLanguageTypeC_plus_plus || + language == eLanguageTypeC_plus_plus_03 || + language == eLanguageTypeC_plus_plus_11 || + language == eLanguageTypeC_plus_plus_14) + return new ItaniumABILanguageRuntime(process); + else + return nullptr; +} + +class CommandObjectMultiwordItaniumABI_Demangle : public CommandObjectParsed { +public: + CommandObjectMultiwordItaniumABI_Demangle(CommandInterpreter &interpreter) + : CommandObjectParsed(interpreter, "demangle", + "Demangle a C++ mangled name.", + "language cplusplus demangle") { + CommandArgumentEntry arg; + CommandArgumentData index_arg; + + // Define the first (and only) variant of this arg. + index_arg.arg_type = eArgTypeSymbol; + index_arg.arg_repetition = eArgRepeatPlus; + + // There is only one variant this argument could be; put it into the + // argument entry. + arg.push_back(index_arg); + + // Push the data for the first argument into the m_arguments vector. + m_arguments.push_back(arg); + } + + ~CommandObjectMultiwordItaniumABI_Demangle() override = default; + +protected: + bool DoExecute(Args &command, CommandReturnObject &result) override { + bool demangled_any = false; + bool error_any = false; + for (auto &entry : command.entries()) { + if (entry.ref().empty()) + continue; + + // the actual Mangled class should be strict about this, but on the + // command line if you're copying mangled names out of 'nm' on Darwin, + // they will come out with an extra underscore - be willing to strip this + // on behalf of the user. This is the moral equivalent of the -_/-n + // options to c++filt + auto name = entry.ref(); + if (name.startswith("__Z")) + name = name.drop_front(); + + Mangled mangled(name); + if (mangled.GuessLanguage() == lldb::eLanguageTypeC_plus_plus) { + ConstString demangled( + mangled.GetDisplayDemangledName(lldb::eLanguageTypeC_plus_plus)); + demangled_any = true; + result.AppendMessageWithFormat("%s ---> %s\n", entry.c_str(), + demangled.GetCString()); + } else { + error_any = true; + result.AppendErrorWithFormat("%s is not a valid C++ mangled name\n", + entry.ref().str().c_str()); + } + } + + result.SetStatus( + error_any ? lldb::eReturnStatusFailed + : (demangled_any ? lldb::eReturnStatusSuccessFinishResult + : lldb::eReturnStatusSuccessFinishNoResult)); + return result.Succeeded(); + } +}; + +class CommandObjectMultiwordItaniumABI : public CommandObjectMultiword { +public: + CommandObjectMultiwordItaniumABI(CommandInterpreter &interpreter) + : CommandObjectMultiword( + interpreter, "cplusplus", + "Commands for operating on the C++ language runtime.", + "cplusplus <subcommand> [<subcommand-options>]") { + LoadSubCommand( + "demangle", + CommandObjectSP( + new CommandObjectMultiwordItaniumABI_Demangle(interpreter))); + } + + ~CommandObjectMultiwordItaniumABI() override = default; +}; + +void ItaniumABILanguageRuntime::Initialize() { + PluginManager::RegisterPlugin( + GetPluginNameStatic(), "Itanium ABI for the C++ language", CreateInstance, + [](CommandInterpreter &interpreter) -> lldb::CommandObjectSP { + return CommandObjectSP( + new CommandObjectMultiwordItaniumABI(interpreter)); + }); +} + +void ItaniumABILanguageRuntime::Terminate() { + PluginManager::UnregisterPlugin(CreateInstance); +} + +lldb_private::ConstString ItaniumABILanguageRuntime::GetPluginNameStatic() { + static ConstString g_name("itanium"); + return g_name; +} + +// PluginInterface protocol +lldb_private::ConstString ItaniumABILanguageRuntime::GetPluginName() { + return GetPluginNameStatic(); +} + +uint32_t ItaniumABILanguageRuntime::GetPluginVersion() { return 1; } + +BreakpointResolverSP ItaniumABILanguageRuntime::CreateExceptionResolver( + Breakpoint *bkpt, bool catch_bp, bool throw_bp) { + return CreateExceptionResolver(bkpt, catch_bp, throw_bp, false); +} + +BreakpointResolverSP ItaniumABILanguageRuntime::CreateExceptionResolver( + Breakpoint *bkpt, bool catch_bp, bool throw_bp, bool for_expressions) { + // One complication here is that most users DON'T want to stop at + // __cxa_allocate_expression, but until we can do anything better with + // predicting unwinding the expression parser does. So we have two forms of + // the exception breakpoints, one for expressions that leaves out + // __cxa_allocate_exception, and one that includes it. The + // SetExceptionBreakpoints does the latter, the CreateExceptionBreakpoint in + // the runtime the former. + static const char *g_catch_name = "__cxa_begin_catch"; + static const char *g_throw_name1 = "__cxa_throw"; + static const char *g_throw_name2 = "__cxa_rethrow"; + static const char *g_exception_throw_name = "__cxa_allocate_exception"; + std::vector<const char *> exception_names; + exception_names.reserve(4); + if (catch_bp) + exception_names.push_back(g_catch_name); + + if (throw_bp) { + exception_names.push_back(g_throw_name1); + exception_names.push_back(g_throw_name2); + } + + if (for_expressions) + exception_names.push_back(g_exception_throw_name); + + BreakpointResolverSP resolver_sp(new BreakpointResolverName( + bkpt, exception_names.data(), exception_names.size(), + eFunctionNameTypeBase, eLanguageTypeUnknown, 0, eLazyBoolNo)); + + return resolver_sp; +} + +lldb::SearchFilterSP ItaniumABILanguageRuntime::CreateExceptionSearchFilter() { + Target &target = m_process->GetTarget(); + + FileSpecList filter_modules; + if (target.GetArchitecture().GetTriple().getVendor() == llvm::Triple::Apple) { + // Limit the number of modules that are searched for these breakpoints for + // Apple binaries. + filter_modules.EmplaceBack("libc++abi.dylib"); + filter_modules.EmplaceBack("libSystem.B.dylib"); + } + return target.GetSearchFilterForModuleList(&filter_modules); +} + +lldb::BreakpointSP ItaniumABILanguageRuntime::CreateExceptionBreakpoint( + bool catch_bp, bool throw_bp, bool for_expressions, bool is_internal) { + Target &target = m_process->GetTarget(); + FileSpecList filter_modules; + BreakpointResolverSP exception_resolver_sp = + CreateExceptionResolver(nullptr, catch_bp, throw_bp, for_expressions); + SearchFilterSP filter_sp(CreateExceptionSearchFilter()); + const bool hardware = false; + const bool resolve_indirect_functions = false; + return target.CreateBreakpoint(filter_sp, exception_resolver_sp, is_internal, + hardware, resolve_indirect_functions); +} + +void ItaniumABILanguageRuntime::SetExceptionBreakpoints() { + if (!m_process) + return; + + const bool catch_bp = false; + const bool throw_bp = true; + const bool is_internal = true; + const bool for_expressions = true; + + // For the exception breakpoints set by the Expression parser, we'll be a + // little more aggressive and stop at exception allocation as well. + + if (m_cxx_exception_bp_sp) { + m_cxx_exception_bp_sp->SetEnabled(true); + } else { + m_cxx_exception_bp_sp = CreateExceptionBreakpoint( + catch_bp, throw_bp, for_expressions, is_internal); + if (m_cxx_exception_bp_sp) + m_cxx_exception_bp_sp->SetBreakpointKind("c++ exception"); + } +} + +void ItaniumABILanguageRuntime::ClearExceptionBreakpoints() { + if (!m_process) + return; + + if (m_cxx_exception_bp_sp) { + m_cxx_exception_bp_sp->SetEnabled(false); + } +} + +bool ItaniumABILanguageRuntime::ExceptionBreakpointsAreSet() { + return m_cxx_exception_bp_sp && m_cxx_exception_bp_sp->IsEnabled(); +} + +bool ItaniumABILanguageRuntime::ExceptionBreakpointsExplainStop( + lldb::StopInfoSP stop_reason) { + if (!m_process) + return false; + + if (!stop_reason || stop_reason->GetStopReason() != eStopReasonBreakpoint) + return false; + + uint64_t break_site_id = stop_reason->GetValue(); + return m_process->GetBreakpointSiteList().BreakpointSiteContainsBreakpoint( + break_site_id, m_cxx_exception_bp_sp->GetID()); +} + +ValueObjectSP ItaniumABILanguageRuntime::GetExceptionObjectForThread( + ThreadSP thread_sp) { + if (!thread_sp->SafeToCallFunctions()) + return {}; + + ClangASTContext *clang_ast_context = + ClangASTContext::GetScratch(m_process->GetTarget()); + if (!clang_ast_context) + return {}; + + CompilerType voidstar = + clang_ast_context->GetBasicType(eBasicTypeVoid).GetPointerType(); + + DiagnosticManager diagnostics; + ExecutionContext exe_ctx; + EvaluateExpressionOptions options; + + options.SetUnwindOnError(true); + options.SetIgnoreBreakpoints(true); + options.SetStopOthers(true); + options.SetTimeout(m_process->GetUtilityExpressionTimeout()); + options.SetTryAllThreads(false); + thread_sp->CalculateExecutionContext(exe_ctx); + + const ModuleList &modules = m_process->GetTarget().GetImages(); + SymbolContextList contexts; + SymbolContext context; + + modules.FindSymbolsWithNameAndType( + ConstString("__cxa_current_exception_type"), eSymbolTypeCode, contexts); + contexts.GetContextAtIndex(0, context); + if (!context.symbol) { + return {}; + } + Address addr = context.symbol->GetAddress(); + + Status error; + FunctionCaller *function_caller = + m_process->GetTarget().GetFunctionCallerForLanguage( + eLanguageTypeC, voidstar, addr, ValueList(), "caller", error); + + ExpressionResults func_call_ret; + Value results; + func_call_ret = function_caller->ExecuteFunction(exe_ctx, nullptr, options, + diagnostics, results); + if (func_call_ret != eExpressionCompleted || !error.Success()) { + return ValueObjectSP(); + } + + size_t ptr_size = m_process->GetAddressByteSize(); + addr_t result_ptr = results.GetScalar().ULongLong(LLDB_INVALID_ADDRESS); + addr_t exception_addr = + m_process->ReadPointerFromMemory(result_ptr - ptr_size, error); + + if (!error.Success()) { + return ValueObjectSP(); + } + + lldb_private::formatters::InferiorSizedWord exception_isw(exception_addr, + *m_process); + ValueObjectSP exception = ValueObject::CreateValueObjectFromData( + "exception", exception_isw.GetAsData(m_process->GetByteOrder()), exe_ctx, + voidstar); + exception = exception->GetDynamicValue(eDynamicDontRunTarget); + + return exception; +} + +TypeAndOrName ItaniumABILanguageRuntime::GetDynamicTypeInfo( + const lldb_private::Address &vtable_addr) { + std::lock_guard<std::mutex> locker(m_dynamic_type_map_mutex); + DynamicTypeCache::const_iterator pos = m_dynamic_type_map.find(vtable_addr); + if (pos == m_dynamic_type_map.end()) + return TypeAndOrName(); + else + return pos->second; +} + +void ItaniumABILanguageRuntime::SetDynamicTypeInfo( + const lldb_private::Address &vtable_addr, const TypeAndOrName &type_info) { + std::lock_guard<std::mutex> locker(m_dynamic_type_map_mutex); + m_dynamic_type_map[vtable_addr] = type_info; +} |