lldb/source/Target/ThreadPlan.cpp

//===-- ThreadPlan.cpp ------------------------------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

// C Includes
// C++ Includes
// Other libraries and framework includes
// Project includes
#include "lldb/Target/ThreadPlan.h"
#include "lldb/Core/Debugger.h"
#include "lldb/Core/Log.h"
#include "lldb/Core/State.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Target/Thread.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/Target.h"
#include "lldb/Utility/ConvertEnum.h"

using namespace lldb;
using namespace lldb_private;

//----------------------------------------------------------------------
// ThreadPlan constructor
//----------------------------------------------------------------------
ThreadPlan::ThreadPlan(ThreadPlanKind kind, const char *name, Thread &thread, Vote stop_vote, Vote run_vote)
    : m_thread(thread),
      m_stop_vote(stop_vote),
      m_run_vote(run_vote),
      m_kind(kind),
      m_name(name),
      m_plan_complete_mutex(),
      m_cached_plan_explains_stop(eLazyBoolCalculate),
      m_plan_complete(false),
      m_plan_private(false),
      m_okay_to_discard(true),
      m_is_master_plan(false),
      m_plan_succeeded(true)
{
    SetID(GetNextID());
}

//----------------------------------------------------------------------
// Destructor
//----------------------------------------------------------------------
ThreadPlan::~ThreadPlan() = default;

bool
ThreadPlan::PlanExplainsStop (Event *event_ptr)
{
    if (m_cached_plan_explains_stop == eLazyBoolCalculate)
    {
        bool actual_value = DoPlanExplainsStop(event_ptr);
        m_cached_plan_explains_stop = actual_value ? eLazyBoolYes : eLazyBoolNo;
        return actual_value;
    }
    else
    {
        return m_cached_plan_explains_stop == eLazyBoolYes;
    }
}

bool
ThreadPlan::IsPlanComplete ()
{
    std::lock_guard<std::recursive_mutex> guard(m_plan_complete_mutex);
    return m_plan_complete;
}

void
ThreadPlan::SetPlanComplete (bool success)
{
    std::lock_guard<std::recursive_mutex> guard(m_plan_complete_mutex);
    m_plan_complete = true;
    m_plan_succeeded = success;
}

bool
ThreadPlan::MischiefManaged ()
{
    std::lock_guard<std::recursive_mutex> guard(m_plan_complete_mutex);
    // Mark the plan is complete, but don't override the success flag.
    m_plan_complete = true;
    return true;
}

Vote
ThreadPlan::ShouldReportStop (Event *event_ptr)
{
    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));

    if (m_stop_vote == eVoteNoOpinion)
    {
        ThreadPlan *prev_plan = GetPreviousPlan ();
        if (prev_plan)
        {
            Vote prev_vote = prev_plan->ShouldReportStop (event_ptr);
            if (log)
                log->Printf ("ThreadPlan::ShouldReportStop() returning previous thread plan vote: %s", 
                             GetVoteAsCString (prev_vote));
            return prev_vote;
        }
    }
    if (log)
        log->Printf ("ThreadPlan::ShouldReportStop() returning vote: %s", GetVoteAsCString (m_stop_vote));
    return m_stop_vote;
}

Vote
ThreadPlan::ShouldReportRun (Event *event_ptr)
{
    if (m_run_vote == eVoteNoOpinion)
    {
        ThreadPlan *prev_plan = GetPreviousPlan ();
        if (prev_plan)
            return prev_plan->ShouldReportRun (event_ptr);
    }
    return m_run_vote;
}

bool
ThreadPlan::StopOthers ()
{
    ThreadPlan *prev_plan;
    prev_plan = GetPreviousPlan ();
    return (prev_plan == nullptr) ? false : prev_plan->StopOthers();
}

void
ThreadPlan::SetStopOthers (bool new_value)
{
	// SetStopOthers doesn't work up the hierarchy.  You have to set the 
    // explicit ThreadPlan you want to affect.
}

bool
ThreadPlan::WillResume (StateType resume_state, bool current_plan)
{
    m_cached_plan_explains_stop = eLazyBoolCalculate;
    
    if (current_plan)
    {
        Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));

        if (log)
        {
            RegisterContext *reg_ctx = m_thread.GetRegisterContext().get();
            assert (reg_ctx);
            addr_t pc = reg_ctx->GetPC();
            addr_t sp = reg_ctx->GetSP();
            addr_t fp = reg_ctx->GetFP();
            log->Printf("%s Thread #%u (0x%p): tid = 0x%4.4" PRIx64 ", pc = 0x%8.8" PRIx64 ", sp = 0x%8.8" PRIx64 ", fp = 0x%8.8" PRIx64 ", "
                        "plan = '%s', state = %s, stop others = %d", 
                        __FUNCTION__, m_thread.GetIndexID(),
                        static_cast<void*>(&m_thread), m_thread.GetID(),
                        static_cast<uint64_t>(pc), static_cast<uint64_t>(sp),
                        static_cast<uint64_t>(fp), m_name.c_str(),
                        StateAsCString(resume_state), StopOthers());
        }
    }
    return DoWillResume (resume_state, current_plan);
}

lldb::user_id_t
ThreadPlan::GetNextID()
{
    static uint32_t g_nextPlanID = 0;
    return ++g_nextPlanID;
}

void
ThreadPlan::DidPush()
{
}

void
ThreadPlan::WillPop()
{
}

bool
ThreadPlan::OkayToDiscard()
{
    return IsMasterPlan() ? m_okay_to_discard : true;
}

lldb::StateType
ThreadPlan::RunState ()
{
    if (m_tracer_sp && m_tracer_sp->TracingEnabled() && m_tracer_sp->SingleStepEnabled())
        return eStateStepping;
    else
        return GetPlanRunState();
}

bool
ThreadPlan::IsUsuallyUnexplainedStopReason(lldb::StopReason reason)
{
    switch (reason)
    {
        case eStopReasonWatchpoint:
        case eStopReasonSignal:
        case eStopReasonException:
        case eStopReasonExec:
        case eStopReasonThreadExiting:
        case eStopReasonInstrumentation:
            return true;
        default:
            return false;
    }
}

//----------------------------------------------------------------------
// ThreadPlanNull
//----------------------------------------------------------------------

ThreadPlanNull::ThreadPlanNull (Thread &thread) :
    ThreadPlan (ThreadPlan::eKindNull,
                "Null Thread Plan",
                thread,
                eVoteNoOpinion,
                eVoteNoOpinion)
{
}

ThreadPlanNull::~ThreadPlanNull() = default;

void
ThreadPlanNull::GetDescription (Stream *s,
                                lldb::DescriptionLevel level)
{
    s->PutCString("Null thread plan - thread has been destroyed.");
}

bool
ThreadPlanNull::ValidatePlan (Stream *error)
{
#ifdef LLDB_CONFIGURATION_DEBUG
    fprintf(stderr, "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64 ", ptid = 0x%" PRIx64 ")",
            LLVM_PRETTY_FUNCTION,
            m_thread.GetID(),
            m_thread.GetProtocolID());
#else
    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_THREAD));
    if (log)
        log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64 ", ptid = 0x%" PRIx64 ")",
                    LLVM_PRETTY_FUNCTION,
                    m_thread.GetID(),
                    m_thread.GetProtocolID());
#endif
    return true;
}

bool
ThreadPlanNull::ShouldStop (Event *event_ptr)
{
#ifdef LLDB_CONFIGURATION_DEBUG
    fprintf(stderr, "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64 ", ptid = 0x%" PRIx64 ")",
            LLVM_PRETTY_FUNCTION,
            m_thread.GetID(),
            m_thread.GetProtocolID());
#else
    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_THREAD));
    if (log)
        log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64 ", ptid = 0x%" PRIx64 ")",
                    LLVM_PRETTY_FUNCTION,
                    m_thread.GetID(),
                    m_thread.GetProtocolID());
#endif
    return true;
}

bool
ThreadPlanNull::WillStop ()
{
#ifdef LLDB_CONFIGURATION_DEBUG
    fprintf(stderr, "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64 ", ptid = 0x%" PRIx64 ")",
            LLVM_PRETTY_FUNCTION,
            m_thread.GetID(),
            m_thread.GetProtocolID());
#else
    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_THREAD));
    if (log)
        log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64 ", ptid = 0x%" PRIx64 ")",
                    LLVM_PRETTY_FUNCTION,
                    m_thread.GetID(),
                    m_thread.GetProtocolID());
#endif
    return true;
}

bool
ThreadPlanNull::DoPlanExplainsStop (Event *event_ptr)
{
#ifdef LLDB_CONFIGURATION_DEBUG
    fprintf(stderr, "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64 ", ptid = 0x%" PRIx64 ")",
            LLVM_PRETTY_FUNCTION,
            m_thread.GetID(),
            m_thread.GetProtocolID());
#else
    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_THREAD));
    if (log)
        log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64 ", ptid = 0x%" PRIx64 ")",
                   LLVM_PRETTY_FUNCTION,
                   m_thread.GetID(),
                   m_thread.GetProtocolID());
#endif
    return true;
}

// The null plan is never done.
bool
ThreadPlanNull::MischiefManaged ()
{
    // The null plan is never done.
#ifdef LLDB_CONFIGURATION_DEBUG
    fprintf(stderr, "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64 ", ptid = 0x%" PRIx64 ")",
            LLVM_PRETTY_FUNCTION,
            m_thread.GetID(),
            m_thread.GetProtocolID());
#else
    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_THREAD));
    if (log)
        log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64 ", ptid = 0x%" PRIx64 ")",
                   LLVM_PRETTY_FUNCTION,
                   m_thread.GetID(),
                   m_thread.GetProtocolID());
#endif
    return false;
}

lldb::StateType
ThreadPlanNull::GetPlanRunState ()
{
    // Not sure what to return here.  This is a dead thread.
#ifdef LLDB_CONFIGURATION_DEBUG
    fprintf(stderr, "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64 ", ptid = 0x%" PRIx64 ")",
            LLVM_PRETTY_FUNCTION,
            m_thread.GetID(),
            m_thread.GetProtocolID());
#else
    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_THREAD));
    if (log)
        log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64 ", ptid = 0x%" PRIx64 ")",
                   LLVM_PRETTY_FUNCTION,
                   m_thread.GetID(),
                   m_thread.GetProtocolID());
#endif
    return eStateRunning;
}