C++ Thread::CalculateProcess方法代码示例

UnwindPlanSP
FuncUnwinders::GetUnwindPlanArchitectureDefaultAtFunctionEntry (Thread& thread)
{
    // Lock the mutex to ensure we can always give out the most appropriate
    // information. We want to make sure if someone requests an unwind
    // plan, that they get one and don't run into a race condition where one
    // thread has started to create the unwind plan and has put it into 
    // the auto_ptr member variable, and have another thread enter this function
    // and return the partially filled pointer contained in the auto_ptr.
    // We also want to make sure that we lock out other unwind plans from
    // being accessed until this one is done creating itself in case someone
    // had some code like:
    //  UnwindPlan *best_unwind_plan = ...GetUnwindPlanAtCallSite (...)
    //  if (best_unwind_plan == NULL)
    //      best_unwind_plan = GetUnwindPlanAtNonCallSite (...)
    Mutex::Locker locker (m_mutex);
    if (m_tried_unwind_arch_default_at_func_entry == false && m_unwind_plan_arch_default_at_func_entry_sp.get() == NULL)
    {
        m_tried_unwind_arch_default_at_func_entry = true;
        Address current_pc;
        ProcessSP process_sp (thread.CalculateProcess());
        if (process_sp)
        {
            ABI *abi = process_sp->GetABI().get();
            if (abi)
            {
                m_unwind_plan_arch_default_at_func_entry_sp.reset (new UnwindPlan (lldb::eRegisterKindGeneric));
                if (m_unwind_plan_arch_default_at_func_entry_sp)
                    abi->CreateFunctionEntryUnwindPlan(*m_unwind_plan_arch_default_at_func_entry_sp);
            }
        }
    }

    return m_unwind_plan_arch_default_sp;
}

UnwindPlanSP
FuncUnwinders::GetUnwindPlanArchitectureDefaultAtFunctionEntry (Thread& thread)
{
    if (m_unwind_plan_arch_default_at_func_entry_sp.get() || m_tried_unwind_arch_default_at_func_entry)
        return m_unwind_plan_arch_default_at_func_entry_sp;

    std::lock_guard<std::recursive_mutex> guard(m_mutex);
    m_tried_unwind_arch_default_at_func_entry = true;

    Address current_pc;
    ProcessSP process_sp (thread.CalculateProcess());
    if (process_sp)
    {
        ABI *abi = process_sp->GetABI().get();
        if (abi)
        {
            m_unwind_plan_arch_default_at_func_entry_sp.reset (new UnwindPlan (lldb::eRegisterKindGeneric));
            if (!abi->CreateFunctionEntryUnwindPlan(*m_unwind_plan_arch_default_at_func_entry_sp))
            {
                m_unwind_plan_arch_default_at_func_entry_sp.reset();
            }
        }
    }

    return m_unwind_plan_arch_default_at_func_entry_sp;
}

//.........这里部分代码省略.........
                                wp_sp->SetHardwareIndex((uint32_t)exc_sub_sub_code);
                            return StopInfo::CreateStopReasonWithWatchpointID(thread, wp_sp->GetID());
                        }
                    }
                    else if (exc_code == 2 ||   // EXC_I386_BPT
                             exc_code == 3)     // EXC_I386_BPTFLT
                    {
                        // KDP returns EXC_I386_BPTFLT for trace breakpoints
                        if (exc_code == 3)
                            is_trace_if_software_breakpoint_missing = true;

                        is_software_breakpoint = true;
                        if (!pc_already_adjusted)
                            pc_decrement = 1;
                    }
                    break;

                case llvm::Triple::ppc:
                case llvm::Triple::ppc64:
                    is_software_breakpoint = exc_code == 1; // EXC_PPC_BREAKPOINT
                    break;
                
                case llvm::Triple::arm:
                    if (exc_code == 0x102)
                    {
                        // It's a watchpoint, then, if the exc_sub_code indicates a known/enabled
                        // data break address from our watchpoint list.
                        lldb::WatchpointSP wp_sp;
                        if (target)
                            wp_sp = target->GetWatchpointList().FindByAddress((lldb::addr_t)exc_sub_code);
                        if (wp_sp && wp_sp->IsEnabled())
                        {
                            // Debugserver may piggyback the hardware index of the fired watchpoint in the exception data.
                            // Set the hardware index if that's the case.
                            if (exc_data_count >=3)
                                wp_sp->SetHardwareIndex((uint32_t)exc_sub_sub_code);
                            return StopInfo::CreateStopReasonWithWatchpointID(thread, wp_sp->GetID());
                        }
                        // EXC_ARM_DA_DEBUG seems to be reused for EXC_BREAKPOINT as well as EXC_BAD_ACCESS
                        if (thread.GetTemporaryResumeState() == eStateStepping)
                            return StopInfo::CreateStopReasonToTrace(thread);
                    }
                    else if (exc_code == 1)
                    {
                        is_software_breakpoint = true;
                        is_trace_if_software_breakpoint_missing = true;
                    }
                    break;

                default:
                    break;
                }

                if (is_software_breakpoint)
                {
                    RegisterContextSP reg_ctx_sp (thread.GetRegisterContext());
                    addr_t pc = reg_ctx_sp->GetPC() - pc_decrement;

                    ProcessSP process_sp (thread.CalculateProcess());

                    lldb::BreakpointSiteSP bp_site_sp;
                    if (process_sp)
                        bp_site_sp = process_sp->GetBreakpointSiteList().FindByAddress(pc);
                    if (bp_site_sp && bp_site_sp->IsEnabled())
                    {
                        // Update the PC if we were asked to do so, but only do
                        // so if we find a breakpoint that we know about cause
                        // this could be a trap instruction in the code
                        if (pc_decrement > 0 && adjust_pc_if_needed)
                            reg_ctx_sp->SetPC (pc);

                        // If the breakpoint is for this thread, then we'll report the hit, but if it is for another thread,
                        // we can just report no reason.  We don't need to worry about stepping over the breakpoint here, that
                        // will be taken care of when the thread resumes and notices that there's a breakpoint under the pc.
                        if (bp_site_sp->ValidForThisThread (&thread))
                            return StopInfo::CreateStopReasonWithBreakpointSiteID (thread, bp_site_sp->GetID());
                        else
                            return StopInfoSP();
                    }
                    
                    // Don't call this a trace if we weren't single stepping this thread.
                    if (is_trace_if_software_breakpoint_missing && thread.GetTemporaryResumeState() == eStateStepping)
                    {
                        return StopInfo::CreateStopReasonToTrace (thread);
                    }
                }
            }
            break;

        case 7:     // EXC_SYSCALL
        case 8:     // EXC_MACH_SYSCALL
        case 9:     // EXC_RPC_ALERT
        case 10:    // EXC_CRASH
            break;
        }
        
        return StopInfoSP(new StopInfoMachException (thread, exc_type, exc_data_count, exc_code, exc_sub_code));
    }
    return StopInfoSP();
}

ThreadPlanSP
ObjCTrampolineHandler::GetStepThroughDispatchPlan (Thread &thread, bool stop_others)
{
    ThreadPlanSP ret_plan_sp;
    lldb::addr_t curr_pc = thread.GetRegisterContext()->GetPC();

    MsgsendMap::iterator pos;
    pos = m_msgSend_map.find (curr_pc);
    if (pos != m_msgSend_map.end())
    {
        Log *log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP);

        const DispatchFunction *this_dispatch = &g_dispatch_functions[(*pos).second];

        lldb::StackFrameSP thread_cur_frame = thread.GetStackFrameAtIndex(0);

        Process *process = thread.CalculateProcess();
        const ABI *abi = process->GetABI();
        if (abi == NULL)
            return ret_plan_sp;

        Target *target = thread.CalculateTarget();

        // FIXME: Since neither the value nor the Clang QualType know their ASTContext,
        // we have to make sure the type we put in our value list comes from the same ASTContext
        // the ABI will use to get the argument values.  THis is the bottom-most frame's module.

        ClangASTContext *clang_ast_context = target->GetScratchClangASTContext();
        ValueList argument_values;
        Value input_value;
        void *clang_void_ptr_type = clang_ast_context->GetVoidPtrType(false);
        input_value.SetValueType (Value::eValueTypeScalar);
        input_value.SetContext (Value::eContextTypeOpaqueClangQualType, clang_void_ptr_type);

        int obj_index;
        int sel_index;

        // If this is a struct return dispatch, then the first argument is the
        // return struct pointer, and the object is the second, and the selector is the third.
        // Otherwise the object is the first and the selector the second.
        if (this_dispatch->stret_return)
        {
            obj_index = 1;
            sel_index = 2;
            argument_values.PushValue(input_value);
            argument_values.PushValue(input_value);
            argument_values.PushValue(input_value);
        }
        else
        {
            obj_index = 0;
            sel_index = 1;
            argument_values.PushValue(input_value);
            argument_values.PushValue(input_value);
        }


        bool success = abi->GetArgumentValues (thread, argument_values);
        if (!success)
            return ret_plan_sp;

        // Okay, the first value here is the object, we actually want the class of that object.
        // For now we're just going with the ISA.
        // FIXME: This should really be the return value of [object class] to properly handle KVO interposition.

        Value isa_value(*(argument_values.GetValueAtIndex(obj_index)));

        // This is a little cheesy, but since object->isa is the first field,
        // making the object value a load address value and resolving it will get
        // the pointer sized data pointed to by that value...
        ExecutionContext exec_ctx;
        thread.Calculate (exec_ctx);

        isa_value.SetValueType(Value::eValueTypeLoadAddress);
        isa_value.ResolveValue(&exec_ctx, clang_ast_context->getASTContext());

        if (this_dispatch->fixedup == DispatchFunction::eFixUpFixed)
        {
            // For the FixedUp method the Selector is actually a pointer to a
            // structure, the second field of which is the selector number.
            Value *sel_value = argument_values.GetValueAtIndex(sel_index);
            sel_value->GetScalar() += process->GetAddressByteSize();
            sel_value->SetValueType(Value::eValueTypeLoadAddress);
            sel_value->ResolveValue(&exec_ctx, clang_ast_context->getASTContext());
        }
        else if (this_dispatch->fixedup == DispatchFunction::eFixUpToFix)
        {
            // FIXME: If the method dispatch is not "fixed up" then the selector is actually a
            // pointer to the string name of the selector.  We need to look that up...
            // For now I'm going to punt on that and just return no plan.
            if (log)
                log->Printf ("Punting on stepping into un-fixed-up method dispatch.");
            return ret_plan_sp;
        }

        // FIXME: If this is a dispatch to the super-class, we need to get the super-class from
        // the class, and disaptch to that instead.
        // But for now I just punt and return no plan.
        if (this_dispatch->is_super)
        {
//.........这里部分代码省略.........

//.........这里部分代码省略.........
                        }
                    }
                    else if (exc_code == 1) // EXC_ARM_BREAKPOINT
                    {
                        is_actual_breakpoint = true;
                        is_trace_if_actual_breakpoint_missing = true;
                    }
                    else if (exc_code == 0) // FIXME not EXC_ARM_BREAKPOINT but a kernel is currently returning this so accept it as indicating a breakpoint until the kernel is fixed
                    {
                        is_actual_breakpoint = true;
                        is_trace_if_actual_breakpoint_missing = true;
                    }
                    break;

                case llvm::Triple::aarch64:
                {
                    if (exc_code == 1 && exc_sub_code == 0) // EXC_ARM_BREAKPOINT
                    {
                        // This is hit when we single instruction step aka MDSCR_EL1 SS bit 0 is set
                        return StopInfo::CreateStopReasonToTrace(thread);
                    }
                    if (exc_code == 0x102) // EXC_ARM_DA_DEBUG
                    {
                        // It's a watchpoint, then, if the exc_sub_code indicates a known/enabled
                        // data break address from our watchpoint list.
                        lldb::WatchpointSP wp_sp;
                        if (target)
                            wp_sp = target->GetWatchpointList().FindByAddress((lldb::addr_t)exc_sub_code);
                        if (wp_sp && wp_sp->IsEnabled())
                        {
                            // Debugserver may piggyback the hardware index of the fired watchpoint in the exception data.
                            // Set the hardware index if that's the case.
                            if (exc_data_count >= 3)
                                wp_sp->SetHardwareIndex((uint32_t)exc_sub_sub_code);
                            return StopInfo::CreateStopReasonWithWatchpointID(thread, wp_sp->GetID());
                        }
                        // EXC_ARM_DA_DEBUG seems to be reused for EXC_BREAKPOINT as well as EXC_BAD_ACCESS
                        if (thread.GetTemporaryResumeState() == eStateStepping)
                            return StopInfo::CreateStopReasonToTrace(thread);
                    }
                    // It looks like exc_sub_code has the 4 bytes of the instruction that triggered the 
                    // exception, i.e. our breakpoint opcode
                    is_actual_breakpoint = exc_code == 1;
                    break;
                }

                default:
                    break;
                }

                if (is_actual_breakpoint)
                {
                    RegisterContextSP reg_ctx_sp (thread.GetRegisterContext());
                    addr_t pc = reg_ctx_sp->GetPC() - pc_decrement;

                    ProcessSP process_sp (thread.CalculateProcess());

                    lldb::BreakpointSiteSP bp_site_sp;
                    if (process_sp)
                        bp_site_sp = process_sp->GetBreakpointSiteList().FindByAddress(pc);
                    if (bp_site_sp && bp_site_sp->IsEnabled())
                    {
                        // Update the PC if we were asked to do so, but only do
                        // so if we find a breakpoint that we know about cause
                        // this could be a trap instruction in the code
                        if (pc_decrement > 0 && adjust_pc_if_needed)
                            reg_ctx_sp->SetPC (pc);

                        // If the breakpoint is for this thread, then we'll report the hit, but if it is for another thread,
                        // we can just report no reason.  We don't need to worry about stepping over the breakpoint here, that
                        // will be taken care of when the thread resumes and notices that there's a breakpoint under the pc.
                        // If we have an operating system plug-in, we might have set a thread specific breakpoint using the
                        // operating system thread ID, so we can't make any assumptions about the thread ID so we must always
                        // report the breakpoint regardless of the thread.
                        if (bp_site_sp->ValidForThisThread (&thread) || thread.GetProcess()->GetOperatingSystem () != NULL)
                            return StopInfo::CreateStopReasonWithBreakpointSiteID (thread, bp_site_sp->GetID());
                        else
                            return StopInfoSP();
                    }

                    // Don't call this a trace if we weren't single stepping this thread.
                    if (is_trace_if_actual_breakpoint_missing && thread.GetTemporaryResumeState() == eStateStepping)
                    {
                        return StopInfo::CreateStopReasonToTrace (thread);
                    }
                }
            }
            break;

        case 7:     // EXC_SYSCALL
        case 8:     // EXC_MACH_SYSCALL
        case 9:     // EXC_RPC_ALERT
        case 10:    // EXC_CRASH
            break;
        }
        
        return StopInfoSP(new StopInfoMachException (thread, exc_type, exc_data_count, exc_code, exc_sub_code));
    }
    return StopInfoSP();
}