C++ (Cpp) ValueObjectSP::CreateConstantValue Examples

Example #1

File: Target.cpp Project: eightcien/lldb

ExecutionResults
Target::EvaluateExpression
(
    const char *expr_cstr,
    StackFrame *frame,
    bool unwind_on_error,
    bool keep_in_memory,
    lldb::ValueObjectSP &result_valobj_sp
)
{
    ExecutionResults execution_results = eExecutionSetupError;

    result_valobj_sp.reset();

    ExecutionContext exe_ctx;
    if (frame)
    {
        frame->CalculateExecutionContext(exe_ctx);
        Error error;
        const uint32_t expr_path_options = StackFrame::eExpressionPathOptionCheckPtrVsMember |
                                           StackFrame::eExpressionPathOptionsNoFragileObjcIvar;
        result_valobj_sp = frame->GetValueForVariableExpressionPath (expr_cstr, expr_path_options, error);
    }
    else if (m_process_sp)
    {
        m_process_sp->CalculateExecutionContext(exe_ctx);
    }
    else
    {
        CalculateExecutionContext(exe_ctx);
    }

    if (result_valobj_sp)
    {
        execution_results = eExecutionCompleted;
        // We got a result from the frame variable expression path above...
        ConstString persistent_variable_name (m_persistent_variables.GetNextPersistentVariableName());

        lldb::ValueObjectSP const_valobj_sp;

        // Check in case our value is already a constant value
        if (result_valobj_sp->GetIsConstant())
        {
            const_valobj_sp = result_valobj_sp;
            const_valobj_sp->SetName (persistent_variable_name);
        }
        else
            const_valobj_sp = result_valobj_sp->CreateConstantValue (exe_ctx.GetBestExecutionContextScope(),
                              persistent_variable_name);

        lldb::ValueObjectSP live_valobj_sp = result_valobj_sp;

        result_valobj_sp = const_valobj_sp;

        ClangExpressionVariableSP clang_expr_variable_sp(m_persistent_variables.CreatePersistentVariable(result_valobj_sp));
        assert (clang_expr_variable_sp.get());

        // Set flags and live data as appropriate

        const Value &result_value = live_valobj_sp->GetValue();

        switch (result_value.GetValueType())
        {
        case Value::eValueTypeHostAddress:
        case Value::eValueTypeFileAddress:
            // we don't do anything with these for now
            break;
        case Value::eValueTypeScalar:
            clang_expr_variable_sp->m_flags |= ClangExpressionVariable::EVIsLLDBAllocated;
            clang_expr_variable_sp->m_flags |= ClangExpressionVariable::EVNeedsAllocation;
            break;
        case Value::eValueTypeLoadAddress:
            clang_expr_variable_sp->m_live_sp = live_valobj_sp;
            clang_expr_variable_sp->m_flags |= ClangExpressionVariable::EVIsProgramReference;
            break;
        }
    }
    else
    {
        // Make sure we aren't just trying to see the value of a persistent
        // variable (something like "$0")
        lldb::ClangExpressionVariableSP persistent_var_sp;
        // Only check for persistent variables the expression starts with a '$'
        if (expr_cstr[0] == '$')
            persistent_var_sp = m_persistent_variables.GetVariable (expr_cstr);

        if (persistent_var_sp)
        {
            result_valobj_sp = persistent_var_sp->GetValueObject ();
            execution_results = eExecutionCompleted;
        }
        else
        {
            const char *prefix = GetExpressionPrefixContentsAsCString();

            execution_results = ClangUserExpression::Evaluate (exe_ctx,
                                unwind_on_error,
                                keep_in_memory,
                                expr_cstr,
                                prefix,
                                result_valobj_sp);
        }
    }
    return execution_results;
}