Files
llvm/lldb/source/Target/ObjCLanguageRuntime.cpp
Greg Clayton ae088e52f3 Now that SymbolFileDWARF supports having types in completely separate .pcm file with "-fmodules -gmodules", each SymbolFileDWARF can reference module DWARF info by looking in other DWARF files. Then if you have 1000 .o files that each reference one or more .pcm files in their debug info, a simple Module::FindTypes(...) call can end up searching the same .pcm file over and over and over. Now all internal FindTypes methods in classes (ModuleList, Module, SymbolFile) now take an extra argument:
llvm::DenseSet<lldb_private::SymbolFile *> &searched_symbol_files
    
Each time a SymbolFile::FindTypes() is called, it needs to check the searched_symbol_files list to make sure it hasn't already been asked to find the type and return immediately if it has been checked. This will stop circular dependencies from also crashing LLDB during type queries. 

This has proven to be an issue when debugging large applications on MacOSX that use DWARF in .o files. 

<rdar://problem/24581488>

llvm-svn: 260434
2016-02-10 21:28:13 +00:00

444 lines
14 KiB
C++

//===-- ObjCLanguageRuntime.cpp ---------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "clang/AST/Type.h"
#include "lldb/Core/Log.h"
#include "lldb/Core/MappedHash.h"
#include "lldb/Core/Module.h"
#include "lldb/Core/PluginManager.h"
#include "lldb/Core/Timer.h"
#include "lldb/Core/ValueObject.h"
#include "lldb/Symbol/ClangASTContext.h"
#include "lldb/Symbol/SymbolContext.h"
#include "lldb/Symbol/SymbolFile.h"
#include "lldb/Symbol/Type.h"
#include "lldb/Symbol/TypeList.h"
#include "lldb/Target/ObjCLanguageRuntime.h"
#include "lldb/Target/Target.h"
#include "llvm/ADT/StringRef.h"
using namespace lldb;
using namespace lldb_private;
//----------------------------------------------------------------------
// Destructor
//----------------------------------------------------------------------
ObjCLanguageRuntime::~ObjCLanguageRuntime()
{
}
ObjCLanguageRuntime::ObjCLanguageRuntime (Process *process) :
LanguageRuntime (process),
m_impl_cache(),
m_has_new_literals_and_indexing (eLazyBoolCalculate),
m_isa_to_descriptor(),
m_hash_to_isa_map(),
m_type_size_cache(),
m_isa_to_descriptor_stop_id (UINT32_MAX),
m_complete_class_cache(),
m_negative_complete_class_cache()
{
}
bool
ObjCLanguageRuntime::AddClass (ObjCISA isa, const ClassDescriptorSP &descriptor_sp, const char *class_name)
{
if (isa != 0)
{
m_isa_to_descriptor[isa] = descriptor_sp;
// class_name is assumed to be valid
m_hash_to_isa_map.insert(std::make_pair(MappedHash::HashStringUsingDJB(class_name), isa));
return true;
}
return false;
}
void
ObjCLanguageRuntime::AddToMethodCache (lldb::addr_t class_addr, lldb::addr_t selector, lldb::addr_t impl_addr)
{
Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
if (log)
{
log->Printf ("Caching: class 0x%" PRIx64 " selector 0x%" PRIx64 " implementation 0x%" PRIx64 ".", class_addr, selector, impl_addr);
}
m_impl_cache.insert (std::pair<ClassAndSel,lldb::addr_t> (ClassAndSel(class_addr, selector), impl_addr));
}
lldb::addr_t
ObjCLanguageRuntime::LookupInMethodCache (lldb::addr_t class_addr, lldb::addr_t selector)
{
MsgImplMap::iterator pos, end = m_impl_cache.end();
pos = m_impl_cache.find (ClassAndSel(class_addr, selector));
if (pos != end)
return (*pos).second;
return LLDB_INVALID_ADDRESS;
}
lldb::TypeSP
ObjCLanguageRuntime::LookupInCompleteClassCache (ConstString &name)
{
CompleteClassMap::iterator complete_class_iter = m_complete_class_cache.find(name);
if (complete_class_iter != m_complete_class_cache.end())
{
// Check the weak pointer to make sure the type hasn't been unloaded
TypeSP complete_type_sp (complete_class_iter->second.lock());
if (complete_type_sp)
return complete_type_sp;
else
m_complete_class_cache.erase(name);
}
if (m_negative_complete_class_cache.count(name) > 0)
return TypeSP();
const ModuleList &modules = m_process->GetTarget().GetImages();
SymbolContextList sc_list;
const size_t matching_symbols = modules.FindSymbolsWithNameAndType (name,
eSymbolTypeObjCClass,
sc_list);
if (matching_symbols)
{
SymbolContext sc;
sc_list.GetContextAtIndex(0, sc);
ModuleSP module_sp(sc.module_sp);
if (!module_sp)
return TypeSP();
const SymbolContext null_sc;
const bool exact_match = true;
const uint32_t max_matches = UINT32_MAX;
TypeList types;
llvm::DenseSet<SymbolFile *> searched_symbol_files;
const uint32_t num_types = module_sp->FindTypes (null_sc,
name,
exact_match,
max_matches,
searched_symbol_files,
types);
if (num_types)
{
uint32_t i;
for (i = 0; i < num_types; ++i)
{
TypeSP type_sp (types.GetTypeAtIndex(i));
if (ClangASTContext::IsObjCObjectOrInterfaceType(type_sp->GetForwardCompilerType ()))
{
if (type_sp->IsCompleteObjCClass())
{
m_complete_class_cache[name] = type_sp;
return type_sp;
}
}
}
}
}
m_negative_complete_class_cache.insert(name);
return TypeSP();
}
size_t
ObjCLanguageRuntime::GetByteOffsetForIvar (CompilerType &parent_qual_type, const char *ivar_name)
{
return LLDB_INVALID_IVAR_OFFSET;
}
bool
ObjCLanguageRuntime::ClassDescriptor::IsPointerValid (lldb::addr_t value,
uint32_t ptr_size,
bool allow_NULLs,
bool allow_tagged,
bool check_version_specific) const
{
if (!value)
return allow_NULLs;
if ( (value % 2) == 1 && allow_tagged)
return true;
if ((value % ptr_size) == 0)
return (check_version_specific ? CheckPointer(value,ptr_size) : true);
else
return false;
}
ObjCLanguageRuntime::ObjCISA
ObjCLanguageRuntime::GetISA(const ConstString &name)
{
ISAToDescriptorIterator pos = GetDescriptorIterator (name);
if (pos != m_isa_to_descriptor.end())
return pos->first;
return 0;
}
ObjCLanguageRuntime::ISAToDescriptorIterator
ObjCLanguageRuntime::GetDescriptorIterator (const ConstString &name)
{
ISAToDescriptorIterator end = m_isa_to_descriptor.end();
if (name)
{
UpdateISAToDescriptorMap();
if (m_hash_to_isa_map.empty())
{
// No name hashes were provided, we need to just linearly power through the
// names and find a match
for (ISAToDescriptorIterator pos = m_isa_to_descriptor.begin(); pos != end; ++pos)
{
if (pos->second->GetClassName() == name)
return pos;
}
}
else
{
// Name hashes were provided, so use them to efficiently lookup name to isa/descriptor
const uint32_t name_hash = MappedHash::HashStringUsingDJB (name.GetCString());
std::pair <HashToISAIterator, HashToISAIterator> range = m_hash_to_isa_map.equal_range(name_hash);
for (HashToISAIterator range_pos = range.first; range_pos != range.second; ++range_pos)
{
ISAToDescriptorIterator pos = m_isa_to_descriptor.find (range_pos->second);
if (pos != m_isa_to_descriptor.end())
{
if (pos->second->GetClassName() == name)
return pos;
}
}
}
}
return end;
}
std::pair<ObjCLanguageRuntime::ISAToDescriptorIterator,ObjCLanguageRuntime::ISAToDescriptorIterator>
ObjCLanguageRuntime::GetDescriptorIteratorPair (bool update_if_needed)
{
if (update_if_needed)
UpdateISAToDescriptorMapIfNeeded();
return std::pair<ObjCLanguageRuntime::ISAToDescriptorIterator,
ObjCLanguageRuntime::ISAToDescriptorIterator>(
m_isa_to_descriptor.begin(),
m_isa_to_descriptor.end());
}
ObjCLanguageRuntime::ObjCISA
ObjCLanguageRuntime::GetParentClass(ObjCLanguageRuntime::ObjCISA isa)
{
ClassDescriptorSP objc_class_sp (GetClassDescriptorFromISA(isa));
if (objc_class_sp)
{
ClassDescriptorSP objc_super_class_sp (objc_class_sp->GetSuperclass());
if (objc_super_class_sp)
return objc_super_class_sp->GetISA();
}
return 0;
}
ConstString
ObjCLanguageRuntime::GetActualTypeName(ObjCLanguageRuntime::ObjCISA isa)
{
ClassDescriptorSP objc_class_sp (GetNonKVOClassDescriptor(isa));
if (objc_class_sp)
return objc_class_sp->GetClassName();
return ConstString();
}
ObjCLanguageRuntime::ClassDescriptorSP
ObjCLanguageRuntime::GetClassDescriptorFromClassName (const ConstString &class_name)
{
ISAToDescriptorIterator pos = GetDescriptorIterator (class_name);
if (pos != m_isa_to_descriptor.end())
return pos->second;
return ClassDescriptorSP();
}
ObjCLanguageRuntime::ClassDescriptorSP
ObjCLanguageRuntime::GetClassDescriptor (ValueObject& valobj)
{
ClassDescriptorSP objc_class_sp;
// if we get an invalid VO (which might still happen when playing around
// with pointers returned by the expression parser, don't consider this
// a valid ObjC object)
if (valobj.GetCompilerType().IsValid())
{
addr_t isa_pointer = valobj.GetPointerValue();
if (isa_pointer != LLDB_INVALID_ADDRESS)
{
ExecutionContext exe_ctx (valobj.GetExecutionContextRef());
Process *process = exe_ctx.GetProcessPtr();
if (process)
{
Error error;
ObjCISA isa = process->ReadPointerFromMemory(isa_pointer, error);
if (isa != LLDB_INVALID_ADDRESS)
objc_class_sp = GetClassDescriptorFromISA (isa);
}
}
}
return objc_class_sp;
}
ObjCLanguageRuntime::ClassDescriptorSP
ObjCLanguageRuntime::GetNonKVOClassDescriptor (ValueObject& valobj)
{
ObjCLanguageRuntime::ClassDescriptorSP objc_class_sp (GetClassDescriptor (valobj));
if (objc_class_sp)
{
if (!objc_class_sp->IsKVO())
return objc_class_sp;
ClassDescriptorSP non_kvo_objc_class_sp(objc_class_sp->GetSuperclass());
if (non_kvo_objc_class_sp && non_kvo_objc_class_sp->IsValid())
return non_kvo_objc_class_sp;
}
return ClassDescriptorSP();
}
ObjCLanguageRuntime::ClassDescriptorSP
ObjCLanguageRuntime::GetClassDescriptorFromISA (ObjCISA isa)
{
if (isa)
{
UpdateISAToDescriptorMap();
ObjCLanguageRuntime::ISAToDescriptorIterator pos = m_isa_to_descriptor.find(isa);
if (pos != m_isa_to_descriptor.end())
return pos->second;
}
return ClassDescriptorSP();
}
ObjCLanguageRuntime::ClassDescriptorSP
ObjCLanguageRuntime::GetNonKVOClassDescriptor (ObjCISA isa)
{
if (isa)
{
ClassDescriptorSP objc_class_sp = GetClassDescriptorFromISA (isa);
if (objc_class_sp && objc_class_sp->IsValid())
{
if (!objc_class_sp->IsKVO())
return objc_class_sp;
ClassDescriptorSP non_kvo_objc_class_sp(objc_class_sp->GetSuperclass());
if (non_kvo_objc_class_sp && non_kvo_objc_class_sp->IsValid())
return non_kvo_objc_class_sp;
}
}
return ClassDescriptorSP();
}
CompilerType
ObjCLanguageRuntime::EncodingToType::RealizeType (const char* name, bool for_expression)
{
if (m_scratch_ast_ctx_ap)
return RealizeType(*m_scratch_ast_ctx_ap, name, for_expression);
return CompilerType();
}
CompilerType
ObjCLanguageRuntime::EncodingToType::RealizeType (ClangASTContext& ast_ctx, const char* name, bool for_expression)
{
clang::ASTContext *clang_ast = ast_ctx.getASTContext();
if (!clang_ast)
return CompilerType();
return RealizeType(*clang_ast, name, for_expression);
}
ObjCLanguageRuntime::EncodingToType::~EncodingToType() {}
ObjCLanguageRuntime::EncodingToTypeSP
ObjCLanguageRuntime::GetEncodingToType ()
{
return nullptr;
}
bool
ObjCLanguageRuntime::GetTypeBitSize (const CompilerType& compiler_type,
uint64_t &size)
{
void *opaque_ptr = compiler_type.GetOpaqueQualType();
size = m_type_size_cache.Lookup(opaque_ptr);
// an ObjC object will at least have an ISA, so 0 is definitely not OK
if (size > 0)
return true;
ClassDescriptorSP class_descriptor_sp = GetClassDescriptorFromClassName(compiler_type.GetTypeName());
if (!class_descriptor_sp)
return false;
int32_t max_offset = INT32_MIN;
uint64_t sizeof_max = 0;
bool found = false;
for (size_t idx = 0;
idx < class_descriptor_sp->GetNumIVars();
idx++)
{
const auto& ivar = class_descriptor_sp->GetIVarAtIndex(idx);
int32_t cur_offset = ivar.m_offset;
if (cur_offset > max_offset)
{
max_offset = cur_offset;
sizeof_max = ivar.m_size;
found = true;
}
}
size = 8 * (max_offset + sizeof_max);
if (found)
m_type_size_cache.Insert(opaque_ptr, size);
return found;
}
//------------------------------------------------------------------
// Exception breakpoint Precondition class for ObjC:
//------------------------------------------------------------------
void
ObjCLanguageRuntime::ObjCExceptionPrecondition::AddClassName(const char *class_name)
{
m_class_names.insert(class_name);
}
ObjCLanguageRuntime::ObjCExceptionPrecondition::ObjCExceptionPrecondition()
{
}
bool
ObjCLanguageRuntime::ObjCExceptionPrecondition::EvaluatePrecondition(StoppointCallbackContext &context)
{
return true;
}
void
ObjCLanguageRuntime::ObjCExceptionPrecondition::GetDescription(Stream &stream, lldb::DescriptionLevel level)
{
}
Error
ObjCLanguageRuntime::ObjCExceptionPrecondition::ConfigurePrecondition(Args &args)
{
Error error;
if (args.GetArgumentCount() > 0)
error.SetErrorString("The ObjC Exception breakpoint doesn't support extra options.");
return error;
}