Files
clang-p2996/lldb/source/Target/ThreadPlanTestCondition.cpp
Greg Clayton e1cd1be6d6 Switching back to using std::tr1::shared_ptr. We originally switched away
due to RTTI worries since llvm and clang don't use RTTI, but I was able to 
switch back with no issues as far as I can tell. Once the RTTI issue wasn't
an issue, we were looking for a way to properly track weak pointers to objects
to solve some of the threading issues we have been running into which naturally
led us back to std::tr1::weak_ptr. We also wanted the ability to make a shared 
pointer from just a pointer, which is also easily solved using the 
std::tr1::enable_shared_from_this class. 

The main reason for this move back is so we can start properly having weak
references to objects. Currently a lldb_private::Thread class has a refrence
to its parent lldb_private::Process. This doesn't work well when we now hand
out a SBThread object that contains a shared pointer to a lldb_private::Thread
as this SBThread can be held onto by external clients and if they end up
using one of these objects we can easily crash.

So the next task is to start adopting std::tr1::weak_ptr where ever it makes
sense which we can do with lldb_private::Debugger, lldb_private::Target,
lldb_private::Process, lldb_private::Thread, lldb_private::StackFrame, and
many more objects now that they are no longer using intrusive ref counted
pointer objects (you can't do std::tr1::weak_ptr functionality with intrusive
pointers).

llvm-svn: 149207
2012-01-29 20:56:30 +00:00

195 lines
6.0 KiB
C++

//===-- ThreadPlanTestCondition.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/Target/ThreadPlanTestCondition.h"
// C Includes
// C++ Includes
// Other libraries and framework includes
// Project includes
#include "lldb/lldb-private-log.h"
#include "lldb/Breakpoint/Breakpoint.h"
#include "lldb/Breakpoint/BreakpointLocation.h"
#include "lldb/Core/Log.h"
#include "lldb/Core/Stream.h"
#include "lldb/Core/Value.h"
#include "lldb/Core/ValueObject.h"
#include "lldb/Symbol/Function.h"
#include "lldb/Symbol/Symbol.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Target/StopInfo.h"
#include "lldb/Target/Thread.h"
using namespace lldb;
using namespace lldb_private;
//----------------------------------------------------------------------
// ThreadPlanTestCondition: Step through a stack range, either stepping over or into
// based on the value of \a type.
//----------------------------------------------------------------------
ThreadPlanTestCondition::ThreadPlanTestCondition (Thread& thread,
ExecutionContext &exe_ctx,
ClangUserExpression *expression,
const BreakpointLocationSP &break_loc_sp,
bool stop_others) :
ThreadPlan (ThreadPlan::eKindTestCondition, "test condition", thread, eVoteNoOpinion, eVoteNoOpinion),
m_expression (expression),
m_exe_ctx (exe_ctx),
m_break_loc_sp (break_loc_sp),
m_did_stop (false),
m_stop_others (stop_others)
{
}
ThreadPlanTestCondition::~ThreadPlanTestCondition ()
{
}
bool
ThreadPlanTestCondition::ValidatePlan (Stream *error)
{
return true;
}
void
ThreadPlanTestCondition::GetDescription (Stream *s, lldb::DescriptionLevel level)
{
if (m_expression)
s->Printf("Thread plan to test condition: \"%s\".", m_expression->GetUserText());
else
s->Printf("Thread plan to test unspecified condition.");
}
bool
ThreadPlanTestCondition::ShouldStop (Event *event_ptr)
{
LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
if (m_thread.IsThreadPlanDone(m_expression_plan_sp.get()))
{
lldb::ClangExpressionVariableSP expr_result;
StreamString error_stream;
m_expression->FinalizeJITExecution(error_stream, m_exe_ctx, expr_result);
ValueObjectSP result_sp (expr_result->GetValueObject());
if (result_sp)
{
// FIXME: This is not the right answer, we should have a "GetValueAsBoolean..."
Scalar scalar_value;
if (result_sp->ResolveValue (scalar_value))
{
if (scalar_value.ULongLong(1) == 0)
m_did_stop = false;
else
m_did_stop = true;
}
if (log)
log->Printf("Condition successfully evaluated, result is %s.\n", m_did_stop ? "true" : "false");
}
else
{
if (log)
log->Printf("Failed to get a result from the expression, error: \"%s\"\n", error_stream.GetData());
m_did_stop = true;
}
}
else if (m_exe_ctx.GetThreadRef().WasThreadPlanDiscarded (m_expression_plan_sp.get()))
{
if (log)
log->Printf("ExecuteExpression thread plan was discarded.\n");
m_did_stop = true;
}
// One tricky bit, somebody might have disabled/deleted the breakpoint while we were running this condition, if so we
// should just continue. If the breakpoint gets disabled, then its "site" will be null'ed out, so we can't report
// this as a breakpoint event any more, since we can't reconstruct it's site. So just pass the event on.
if (!m_break_loc_sp->IsEnabled())
{
m_did_stop = false;
}
else
{
// Now we have to change the event to a breakpoint event and mark it up appropriately:
Process::ProcessEventData *new_data = new Process::ProcessEventData (m_thread.GetProcess().shared_from_this(), eStateStopped);
event_ptr->SetData(new_data);
event_ptr->SetType(Process::eBroadcastBitStateChanged);
SetStopInfo(StopInfo::CreateStopReasonWithBreakpointSiteID (m_thread,
m_break_loc_sp->GetBreakpointSite()->GetID(),
m_did_stop));
if (m_did_stop)
{
Process::ProcessEventData::SetRestartedInEvent (event_ptr, false);
}
else
{
Process::ProcessEventData::SetRestartedInEvent (event_ptr, true);
}
}
SetPlanComplete();
return m_did_stop;
}
bool
ThreadPlanTestCondition::PlanExplainsStop ()
{
// We explain all stops, and we just can the execution and return true if we stop for any
// reason other than that our expression execution is done.
return true;
}
Vote
ThreadPlanTestCondition::ShouldReportStop (Event *event_ptr)
{
if (m_did_stop)
{
return eVoteYes;
}
else
{
return eVoteNo;
}
}
void
ThreadPlanTestCondition::DidPush()
{
StreamString error_stream;
m_expression_plan_sp.reset(m_expression->GetThreadPlanToExecuteJITExpression (error_stream, m_exe_ctx));
m_thread.QueueThreadPlan (m_expression_plan_sp, false);
}
bool
ThreadPlanTestCondition::StopOthers ()
{
return m_stop_others;
}
bool
ThreadPlanTestCondition::WillStop ()
{
return true;
}
StateType
ThreadPlanTestCondition::GetPlanRunState ()
{
return eStateRunning;
}
bool
ThreadPlanTestCondition::MischiefManaged ()
{
// If we get a stop we're done, we don't puase in the middle of
// condition execution.
return true;
}