| //===-- ItaniumABILanguageRuntime.cpp --------------------------------------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "ItaniumABILanguageRuntime.h" |
| |
| #include "lldb/Breakpoint/BreakpointLocation.h" |
| #include "lldb/Core/ConstString.h" |
| #include "lldb/Core/Error.h" |
| #include "lldb/Core/Module.h" |
| #include "lldb/Core/PluginManager.h" |
| #include "lldb/Core/Scalar.h" |
| #include "lldb/Core/ValueObject.h" |
| #include "lldb/Core/ValueObjectMemory.h" |
| #include "lldb/Symbol/ClangASTContext.h" |
| #include "lldb/Target/Process.h" |
| #include "lldb/Target/RegisterContext.h" |
| #include "lldb/Target/StopInfo.h" |
| #include "lldb/Target/Target.h" |
| #include "lldb/Target/Thread.h" |
| |
| #include <vector> |
| |
| using namespace lldb; |
| using namespace lldb_private; |
| |
| static const char *pluginName = "ItaniumABILanguageRuntime"; |
| static const char *pluginDesc = "Itanium ABI for the C++ language"; |
| static const char *pluginShort = "language.itanium"; |
| static const char *vtable_demangled_prefix = "vtable for "; |
| |
| bool |
| ItaniumABILanguageRuntime::CouldHaveDynamicValue (ValueObject &in_value) |
| { |
| return in_value.IsPossibleCPlusPlusDynamicType(); |
| } |
| |
| bool |
| ItaniumABILanguageRuntime::GetDynamicTypeAndAddress (ValueObject &in_value, |
| lldb::DynamicValueType use_dynamic, |
| TypeAndOrName &class_type_or_name, |
| Address &dynamic_address) |
| { |
| // 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. |
| // |
| |
| // Only a pointer or reference type can have a different dynamic and static type: |
| if (CouldHaveDynamicValue (in_value)) |
| { |
| // FIXME: Can we get the Clang Type and ask it if the thing is really virtual? That would avoid false positives, |
| // at the cost of not looking for the dynamic type of objects if DWARF->Clang gets it wrong. |
| |
| // 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; |
| |
| Target *target = in_value.GetUpdatePoint().GetTargetSP().get(); |
| Process *process = in_value.GetUpdatePoint().GetProcessSP().get(); |
| |
| char memory_buffer[16]; |
| DataExtractor data(memory_buffer, sizeof(memory_buffer), |
| process->GetByteOrder(), |
| process->GetAddressByteSize()); |
| size_t address_byte_size = process->GetAddressByteSize(); |
| Error error; |
| size_t bytes_read = process->ReadMemory (original_ptr, |
| memory_buffer, |
| address_byte_size, |
| error); |
| if (!error.Success() || (bytes_read != address_byte_size)) |
| { |
| return false; |
| } |
| |
| uint32_t offset_ptr = 0; |
| lldb::addr_t vtable_address_point = data.GetAddress (&offset_ptr); |
| |
| if (offset_ptr == 0) |
| return false; |
| |
| // Now find the symbol that contains this address: |
| |
| SymbolContext sc; |
| Address address_point_address; |
| if (target && !target->GetSectionLoadList().IsEmpty()) |
| { |
| if (target->GetSectionLoadList().ResolveLoadAddress (vtable_address_point, address_point_address)) |
| { |
| target->GetImages().ResolveSymbolContextForAddress (address_point_address, eSymbolContextSymbol, sc); |
| Symbol *symbol = sc.symbol; |
| if (symbol != NULL) |
| { |
| const char *name = symbol->GetMangled().GetDemangledName().AsCString(); |
| if (strstr(name, vtable_demangled_prefix) == 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); |
| class_type_or_name.SetName (class_name); |
| TypeList class_types; |
| uint32_t num_matches = target->GetImages().FindTypes (sc, |
| ConstString(class_name), |
| true, |
| UINT32_MAX, |
| class_types); |
| if (num_matches == 1) |
| { |
| class_type_or_name.SetTypeSP(class_types.GetTypeAtIndex(0)); |
| } |
| else if (num_matches > 1) |
| { |
| for (size_t i = 0; i < num_matches; i++) |
| { |
| lldb::TypeSP this_type(class_types.GetTypeAtIndex(i)); |
| if (this_type) |
| { |
| if (ClangASTContext::IsCXXClassType(this_type->GetClangFullType())) |
| { |
| // 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: |
| |
| clang::ASTContext *in_ast_ctx = in_value.GetClangAST (); |
| clang::ASTContext *this_ast_ctx = this_type->GetClangAST (); |
| if (in_ast_ctx != this_ast_ctx |
| || !ClangASTContext::AreTypesSame (in_ast_ctx, |
| in_value.GetClangType(), |
| this_type->GetClangFullType())) |
| { |
| class_type_or_name.SetTypeSP (this_type); |
| return true; |
| } |
| return false; |
| } |
| } |
| } |
| } |
| else |
| return false; |
| |
| // The offset_to_top is two pointers above the address. |
| Address offset_to_top_address = address_point_address; |
| int64_t slide = -2 * ((int64_t) target->GetArchitecture().GetAddressByteSize()); |
| offset_to_top_address.Slide (slide); |
| |
| Error error; |
| lldb::addr_t offset_to_top_location = offset_to_top_address.GetLoadAddress(target); |
| |
| size_t bytes_read = process->ReadMemory (offset_to_top_location, |
| memory_buffer, |
| address_byte_size, |
| error); |
| |
| if (!error.Success() || (bytes_read != address_byte_size)) |
| { |
| return false; |
| } |
| |
| offset_ptr = 0; |
| int64_t offset_to_top = data.GetMaxS64(&offset_ptr, process->GetAddressByteSize()); |
| |
| // 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 (!target->GetSectionLoadList().ResolveLoadAddress (dynamic_addr, dynamic_address)) |
| { |
| dynamic_address.SetOffset(dynamic_addr); |
| dynamic_address.SetSection(NULL); |
| } |
| return true; |
| } |
| } |
| } |
| } |
| |
| } |
| |
| return false; |
| } |
| |
| bool |
| ItaniumABILanguageRuntime::IsVTableName (const char *name) |
| { |
| if (name == NULL) |
| return false; |
| |
| // Can we maybe ask Clang about this? |
| if (strstr (name, "_vptr$") == name) |
| return true; |
| else |
| return false; |
| } |
| |
| //------------------------------------------------------------------ |
| // Static Functions |
| //------------------------------------------------------------------ |
| lldb_private::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) |
| return new ItaniumABILanguageRuntime (process); |
| else |
| return NULL; |
| } |
| |
| void |
| ItaniumABILanguageRuntime::Initialize() |
| { |
| PluginManager::RegisterPlugin (pluginName, |
| pluginDesc, |
| CreateInstance); |
| } |
| |
| void |
| ItaniumABILanguageRuntime::Terminate() |
| { |
| PluginManager::UnregisterPlugin (CreateInstance); |
| } |
| |
| //------------------------------------------------------------------ |
| // PluginInterface protocol |
| //------------------------------------------------------------------ |
| const char * |
| ItaniumABILanguageRuntime::GetPluginName() |
| { |
| return pluginName; |
| } |
| |
| const char * |
| ItaniumABILanguageRuntime::GetShortPluginName() |
| { |
| return pluginShort; |
| } |
| |
| uint32_t |
| ItaniumABILanguageRuntime::GetPluginVersion() |
| { |
| return 1; |
| } |
| |
| void |
| ItaniumABILanguageRuntime::SetExceptionBreakpoints () |
| { |
| if (!m_process) |
| return; |
| |
| if (!m_cxx_exception_bp_sp) |
| m_cxx_exception_bp_sp = m_process->GetTarget().CreateBreakpoint (NULL, |
| NULL, |
| "__cxa_throw", |
| eFunctionNameTypeBase, |
| true); |
| else |
| m_cxx_exception_bp_sp->SetEnabled (true); |
| |
| if (!m_cxx_exception_alloc_bp_sp) |
| m_cxx_exception_alloc_bp_sp = m_process->GetTarget().CreateBreakpoint (NULL, |
| NULL, |
| "__cxa_allocate", |
| eFunctionNameTypeBase, |
| true); |
| else |
| m_cxx_exception_alloc_bp_sp->SetEnabled (true); |
| } |
| |
| void |
| ItaniumABILanguageRuntime::ClearExceptionBreakpoints () |
| { |
| if (!m_process) |
| return; |
| |
| if (m_cxx_exception_bp_sp.get()) |
| { |
| m_cxx_exception_bp_sp->SetEnabled (false); |
| } |
| |
| if (m_cxx_exception_alloc_bp_sp.get()) |
| { |
| m_cxx_exception_bp_sp->SetEnabled (false); |
| } |
| } |
| |
| 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(); |
| lldb::BreakpointSiteSP bp_site_sp = m_process->GetBreakpointSiteList().FindByID(break_site_id); |
| |
| if (!bp_site_sp) |
| return false; |
| |
| uint32_t num_owners = bp_site_sp->GetNumberOfOwners(); |
| |
| bool check_cxx_exception = false; |
| break_id_t cxx_exception_bid; |
| |
| bool check_cxx_exception_alloc = false; |
| break_id_t cxx_exception_alloc_bid; |
| |
| if (m_cxx_exception_bp_sp) |
| { |
| check_cxx_exception = true; |
| cxx_exception_bid = m_cxx_exception_bp_sp->GetID(); |
| } |
| |
| if (m_cxx_exception_alloc_bp_sp) |
| { |
| check_cxx_exception_alloc = true; |
| cxx_exception_alloc_bid = m_cxx_exception_alloc_bp_sp->GetID(); |
| } |
| |
| for (uint32_t i = 0; i < num_owners; i++) |
| { |
| break_id_t bid = bp_site_sp->GetOwnerAtIndex(i)->GetBreakpoint().GetID(); |
| |
| if ((check_cxx_exception && (bid == cxx_exception_bid)) || |
| (check_cxx_exception_alloc && (bid == cxx_exception_alloc_bid))) |
| return true; |
| } |
| |
| return false; |
| } |