teak-llvm/lldb/source/Core/ValueObjectMemory.cpp
Greg Clayton cc4d0146b4 This checking is part one of trying to add some threading safety to our
internals. The first part of this is to use a new class:

lldb_private::ExecutionContextRef

This class holds onto weak pointers to the target, process, thread and frame
and it also contains the thread ID and frame Stack ID in case the thread and
frame objects go away and come back as new objects that represent the same
logical thread/frame. 

ExecutionContextRef objcets have accessors to access shared pointers for
the target, process, thread and frame which might return NULL if the backing
object is no longer available. This allows for references to persistent program
state without needing to hold a shared pointer to each object and potentially
keeping that object around for longer than it needs to be. 

You can also "Lock" and ExecutionContextRef (which contains weak pointers)
object into an ExecutionContext (which contains strong, or shared pointers)
with code like

ExecutionContext exe_ctx (my_obj->GetExectionContextRef().Lock());

llvm-svn: 150801
2012-02-17 07:49:44 +00:00

282 lines
8.7 KiB
C++

//===-- ValueObjectMemory.cpp ---------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "lldb/Core/ValueObjectMemory.h"
// C Includes
// C++ Includes
// Other libraries and framework includes
// Project includes
#include "lldb/Core/Module.h"
#include "lldb/Core/ValueObjectList.h"
#include "lldb/Core/Value.h"
#include "lldb/Core/ValueObject.h"
#include "lldb/Symbol/ObjectFile.h"
#include "lldb/Symbol/SymbolContext.h"
#include "lldb/Symbol/Type.h"
#include "lldb/Symbol/Variable.h"
#include "lldb/Target/ExecutionContext.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Target/Target.h"
#include "lldb/Target/Thread.h"
using namespace lldb;
using namespace lldb_private;
ValueObjectSP
ValueObjectMemory::Create (ExecutionContextScope *exe_scope,
const char *name,
const Address &address,
lldb::TypeSP &type_sp)
{
return (new ValueObjectMemory (exe_scope, name, address, type_sp))->GetSP();
}
ValueObjectSP
ValueObjectMemory::Create (ExecutionContextScope *exe_scope,
const char *name,
const Address &address,
const ClangASTType &ast_type)
{
return (new ValueObjectMemory (exe_scope, name, address, ast_type))->GetSP();
}
ValueObjectMemory::ValueObjectMemory (ExecutionContextScope *exe_scope,
const char *name,
const Address &address,
lldb::TypeSP &type_sp) :
ValueObject(exe_scope),
m_address (address),
m_type_sp(type_sp),
m_clang_type()
{
// Do not attempt to construct one of these objects with no variable!
assert (m_type_sp.get() != NULL);
SetName (ConstString(name));
m_value.SetContext(Value::eContextTypeLLDBType, m_type_sp.get());
TargetSP target_sp (GetTargetSP());
lldb::addr_t load_address = m_address.GetLoadAddress(target_sp.get());
if (load_address != LLDB_INVALID_ADDRESS)
{
m_value.SetValueType(Value::eValueTypeLoadAddress);
m_value.GetScalar() = load_address;
}
else
{
lldb::addr_t file_address = m_address.GetFileAddress();
if (file_address != LLDB_INVALID_ADDRESS)
{
m_value.SetValueType(Value::eValueTypeFileAddress);
m_value.GetScalar() = file_address;
}
else
{
m_value.GetScalar() = m_address.GetOffset();
m_value.SetValueType (Value::eValueTypeScalar);
}
}
}
ValueObjectMemory::ValueObjectMemory (ExecutionContextScope *exe_scope,
const char *name,
const Address &address,
const ClangASTType &ast_type) :
ValueObject(exe_scope),
m_address (address),
m_type_sp(),
m_clang_type(ast_type)
{
// Do not attempt to construct one of these objects with no variable!
assert (m_clang_type.GetASTContext());
assert (m_clang_type.GetOpaqueQualType());
TargetSP target_sp (GetTargetSP());
SetName (ConstString(name));
m_value.SetContext(Value::eContextTypeClangType, m_clang_type.GetOpaqueQualType());
lldb::addr_t load_address = m_address.GetLoadAddress (target_sp.get());
if (load_address != LLDB_INVALID_ADDRESS)
{
m_value.SetValueType(Value::eValueTypeLoadAddress);
m_value.GetScalar() = load_address;
}
else
{
lldb::addr_t file_address = m_address.GetFileAddress();
if (file_address != LLDB_INVALID_ADDRESS)
{
m_value.SetValueType(Value::eValueTypeFileAddress);
m_value.GetScalar() = file_address;
}
else
{
m_value.GetScalar() = m_address.GetOffset();
m_value.SetValueType (Value::eValueTypeScalar);
}
}
}
ValueObjectMemory::~ValueObjectMemory()
{
}
lldb::clang_type_t
ValueObjectMemory::GetClangType ()
{
if (m_type_sp)
return m_type_sp->GetClangForwardType();
return m_clang_type.GetOpaqueQualType();
}
ConstString
ValueObjectMemory::GetTypeName()
{
if (m_type_sp)
return m_type_sp->GetName();
return ClangASTType::GetConstTypeName (m_clang_type.GetOpaqueQualType());
}
uint32_t
ValueObjectMemory::CalculateNumChildren()
{
if (m_type_sp)
return m_type_sp->GetNumChildren(true);
const bool omit_empty_base_classes = true;
return ClangASTContext::GetNumChildren (m_clang_type.GetASTContext(),
m_clang_type.GetOpaqueQualType(),
omit_empty_base_classes);
}
clang::ASTContext *
ValueObjectMemory::GetClangAST ()
{
if (m_type_sp)
return m_type_sp->GetClangAST();
return m_clang_type.GetASTContext();
}
size_t
ValueObjectMemory::GetByteSize()
{
if (m_type_sp)
return m_type_sp->GetByteSize();
return (m_clang_type.GetClangTypeBitWidth () + 7) / 8;
}
lldb::ValueType
ValueObjectMemory::GetValueType() const
{
// RETHINK: Should this be inherited from somewhere?
return lldb::eValueTypeVariableGlobal;
}
bool
ValueObjectMemory::UpdateValue ()
{
SetValueIsValid (false);
m_error.Clear();
ExecutionContext exe_ctx (GetExecutionContextRef());
Target *target = exe_ctx.GetTargetPtr();
if (target)
{
m_data.SetByteOrder(target->GetArchitecture().GetByteOrder());
m_data.SetAddressByteSize(target->GetArchitecture().GetAddressByteSize());
}
Value old_value(m_value);
if (m_address.IsValid())
{
Value::ValueType value_type = m_value.GetValueType();
switch (value_type)
{
default:
assert(!"Unhandled expression result value kind...");
break;
case Value::eValueTypeScalar:
// The variable value is in the Scalar value inside the m_value.
// We can point our m_data right to it.
m_error = m_value.GetValueAsData (&exe_ctx, GetClangAST(), m_data, 0, GetModule());
break;
case Value::eValueTypeFileAddress:
case Value::eValueTypeLoadAddress:
case Value::eValueTypeHostAddress:
// The DWARF expression result was an address in the inferior
// process. If this variable is an aggregate type, we just need
// the address as the main value as all child variable objects
// will rely upon this location and add an offset and then read
// their own values as needed. If this variable is a simple
// type, we read all data for it into m_data.
// Make sure this type has a value before we try and read it
// If we have a file address, convert it to a load address if we can.
if (value_type == Value::eValueTypeFileAddress && exe_ctx.GetProcessPtr())
{
lldb::addr_t load_addr = m_address.GetLoadAddress(target);
if (load_addr != LLDB_INVALID_ADDRESS)
{
m_value.SetValueType(Value::eValueTypeLoadAddress);
m_value.GetScalar() = load_addr;
}
}
if (ClangASTContext::IsAggregateType (GetClangType()))
{
// this value object represents an aggregate type whose
// children have values, but this object does not. So we
// say we are changed if our location has changed.
SetValueDidChange (value_type != old_value.GetValueType() || m_value.GetScalar() != old_value.GetScalar());
}
else
{
// Copy the Value and set the context to use our Variable
// so it can extract read its value into m_data appropriately
Value value(m_value);
if (m_type_sp)
value.SetContext(Value::eContextTypeLLDBType, m_type_sp.get());
else
value.SetContext(Value::eContextTypeClangType, m_clang_type.GetOpaqueQualType());
m_error = value.GetValueAsData(&exe_ctx, GetClangAST(), m_data, 0, GetModule());
}
break;
}
SetValueIsValid (m_error.Success());
}
return m_error.Success();
}
bool
ValueObjectMemory::IsInScope ()
{
// FIXME: Maybe try to read the memory address, and if that works, then
// we are in scope?
return true;
}
Module *
ValueObjectMemory::GetModule()
{
return m_address.GetModulePtr();
}