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diff --git a/contrib/llvm/tools/lldb/source/Target/ThreadPlanStepThrough.cpp b/contrib/llvm/tools/lldb/source/Target/ThreadPlanStepThrough.cpp
new file mode 100644
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--- /dev/null
+++ b/contrib/llvm/tools/lldb/source/Target/ThreadPlanStepThrough.cpp
@@ -0,0 +1,290 @@
+//===-- ThreadPlanStepThrough.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/ThreadPlanStepThrough.h"
+
+// C Includes
+// C++ Includes
+// Other libraries and framework includes
+// Project includes
+#include "lldb/lldb-private-log.h"
+#include "lldb/Core/Log.h"
+#include "lldb/Core/Stream.h"
+#include "lldb/Target/DynamicLoader.h"
+#include "lldb/Target/ObjCLanguageRuntime.h"
+#include "lldb/Target/Process.h"
+#include "lldb/Target/RegisterContext.h"
+#include "lldb/Target/Target.h"
+#include "lldb/Breakpoint/Breakpoint.h"
+
+using namespace lldb;
+using namespace lldb_private;
+
+//----------------------------------------------------------------------
+// ThreadPlanStepThrough: If the current instruction is a trampoline, step through it
+// If it is the beginning of the prologue of a function, step through that as well.
+// FIXME: At present only handles DYLD trampolines.
+//----------------------------------------------------------------------
+
+ThreadPlanStepThrough::ThreadPlanStepThrough (Thread &thread, StackID &m_stack_id, bool stop_others) :
+    ThreadPlan (ThreadPlan::eKindStepThrough, "Step through trampolines and prologues", thread, eVoteNoOpinion, eVoteNoOpinion),
+    m_start_address (0),
+    m_backstop_bkpt_id (LLDB_INVALID_BREAK_ID),
+    m_backstop_addr(LLDB_INVALID_ADDRESS),
+    m_return_stack_id (m_stack_id),
+    m_stop_others (stop_others)
+{
+
+    LookForPlanToStepThroughFromCurrentPC();
+    
+    // If we don't get a valid step through plan, don't bother to set up a backstop.
+    if (m_sub_plan_sp)
+    {
+        m_start_address = GetThread().GetRegisterContext()->GetPC(0);
+                
+        // We are going to return back to the concrete frame 1, we might pass by some inlined code that we're in 
+        // the middle of by doing this, but it's easier than trying to figure out where the inlined code might return to.
+            
+        StackFrameSP return_frame_sp = m_thread.GetFrameWithStackID (m_stack_id);
+        
+        if (return_frame_sp)
+        {
+            m_backstop_addr = return_frame_sp->GetFrameCodeAddress().GetLoadAddress(m_thread.CalculateTarget().get());
+            Breakpoint *return_bp = m_thread.GetProcess()->GetTarget().CreateBreakpoint (m_backstop_addr, true).get();
+            if (return_bp != NULL)
+            {
+                return_bp->SetThreadID(m_thread.GetID());
+                m_backstop_bkpt_id = return_bp->GetID();
+                return_bp->SetBreakpointKind("step-through-backstop");
+            }
+            Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
+            if (log)
+            {
+                log->Printf ("Setting backstop breakpoint %d at address: 0x%" PRIx64, m_backstop_bkpt_id, m_backstop_addr);
+            }
+        }
+    }
+}
+
+ThreadPlanStepThrough::~ThreadPlanStepThrough ()
+{
+    ClearBackstopBreakpoint ();
+}
+
+void
+ThreadPlanStepThrough::DidPush ()
+{
+    if (m_sub_plan_sp)
+        PushPlan(m_sub_plan_sp);
+}
+
+void
+ThreadPlanStepThrough::LookForPlanToStepThroughFromCurrentPC()
+{
+    m_sub_plan_sp = m_thread.GetProcess()->GetDynamicLoader()->GetStepThroughTrampolinePlan (m_thread, m_stop_others);
+    // If that didn't come up with anything, try the ObjC runtime plugin:
+    if (!m_sub_plan_sp.get())
+    {
+        ObjCLanguageRuntime *objc_runtime = m_thread.GetProcess()->GetObjCLanguageRuntime();
+        if (objc_runtime)
+            m_sub_plan_sp = objc_runtime->GetStepThroughTrampolinePlan (m_thread, m_stop_others);
+    }
+    
+    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
+    if (log)
+    {
+        lldb::addr_t current_address = GetThread().GetRegisterContext()->GetPC(0);
+        if (m_sub_plan_sp)
+        {
+            StreamString s;
+            m_sub_plan_sp->GetDescription(&s, lldb::eDescriptionLevelFull);
+            log->Printf ("Found step through plan from 0x%" PRIx64 ": %s", current_address, s.GetData());
+        }
+        else
+        {
+            log->Printf ("Couldn't find step through plan from address 0x%" PRIx64 ".", current_address);
+        }
+    }
+}
+
+void
+ThreadPlanStepThrough::GetDescription (Stream *s, lldb::DescriptionLevel level)
+{
+    if (level == lldb::eDescriptionLevelBrief)
+        s->Printf ("Step through");
+    else
+    {
+        s->PutCString ("Stepping through trampoline code from: ");
+        s->Address(m_start_address, sizeof (addr_t));
+        if (m_backstop_bkpt_id != LLDB_INVALID_BREAK_ID)
+        {
+            s->Printf (" with backstop breakpoint id: %d at address: ", m_backstop_bkpt_id);
+            s->Address (m_backstop_addr, sizeof (addr_t));
+        }
+        else
+            s->PutCString (" unable to set a backstop breakpoint.");
+    }
+}
+
+bool
+ThreadPlanStepThrough::ValidatePlan (Stream *error)
+{
+    return m_sub_plan_sp.get() != NULL;
+}
+
+bool
+ThreadPlanStepThrough::DoPlanExplainsStop (Event *event_ptr)
+{
+    // If we have a sub-plan, it will have been asked first if we explain the stop, and
+    // we won't get asked.  The only time we would be the one directly asked this question
+    // is if we hit our backstop breakpoint.
+    
+    if (HitOurBackstopBreakpoint())
+        return true;
+    else
+        return false;
+}
+
+bool
+ThreadPlanStepThrough::ShouldStop (Event *event_ptr)
+{
+    // If we've already marked ourselves done, then we're done...
+    if (IsPlanComplete())
+        return true;
+        
+    // First, did we hit the backstop breakpoint?
+    if (HitOurBackstopBreakpoint())
+    {
+        SetPlanComplete(false);
+        return true;
+    }
+
+    // If we don't have a sub-plan, then we're also done (can't see how we would ever get here
+    // without a plan, but just in case.
+    
+    if (!m_sub_plan_sp)
+    {
+        SetPlanComplete();
+        return true;
+    }
+    
+    // If the current sub plan is not done, we don't want to stop.  Actually, we probably won't
+    // ever get here in this state, since we generally won't get asked any questions if out
+    // current sub-plan is not done...
+    if (!m_sub_plan_sp->IsPlanComplete())
+        return false;
+    
+    // If our current sub plan failed, then let's just run to our backstop.  If we can't do that then just stop.
+    if (!m_sub_plan_sp->PlanSucceeded())
+    {
+        if (m_backstop_bkpt_id != LLDB_INVALID_BREAK_ID)
+        {
+            m_sub_plan_sp.reset();
+            return false;
+        }
+        else
+        {
+            SetPlanComplete(false);
+            return true;
+        }
+    }
+        
+    // Next see if there is a specific step through plan at our current pc (these might 
+    // chain, for instance stepping through a dylib trampoline to the objc dispatch function...)
+    LookForPlanToStepThroughFromCurrentPC();
+    if (m_sub_plan_sp)
+    {
+        PushPlan (m_sub_plan_sp);
+        return false;
+    }
+    else
+    {
+        SetPlanComplete();
+        return true;
+    }
+}
+
+bool
+ThreadPlanStepThrough::StopOthers ()
+{
+    return m_stop_others;
+}
+
+StateType
+ThreadPlanStepThrough::GetPlanRunState ()
+{
+    return eStateRunning;
+}
+
+bool
+ThreadPlanStepThrough::DoWillResume (StateType resume_state, bool current_plan)
+{
+    return true;
+}
+
+bool
+ThreadPlanStepThrough::WillStop ()
+{
+    return true;
+}
+
+void
+ThreadPlanStepThrough::ClearBackstopBreakpoint ()
+{
+    if (m_backstop_bkpt_id != LLDB_INVALID_BREAK_ID)
+    {
+        m_thread.GetProcess()->GetTarget().RemoveBreakpointByID (m_backstop_bkpt_id);
+        m_backstop_bkpt_id = LLDB_INVALID_BREAK_ID;
+    }
+}
+
+bool
+ThreadPlanStepThrough::MischiefManaged ()
+{
+    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
+
+    if (!IsPlanComplete())
+    {
+        return false;
+    }
+    else
+    {
+        if (log)
+            log->Printf("Completed step through step plan.");
+            
+        ClearBackstopBreakpoint ();
+        ThreadPlan::MischiefManaged ();
+        return true;
+    }
+}
+
+bool
+ThreadPlanStepThrough::HitOurBackstopBreakpoint()
+{
+    StopInfoSP stop_info_sp(m_thread.GetStopInfo());
+    if (stop_info_sp && stop_info_sp->GetStopReason() == eStopReasonBreakpoint)
+    {
+        break_id_t stop_value = (break_id_t) stop_info_sp->GetValue();
+        BreakpointSiteSP cur_site_sp = m_thread.GetProcess()->GetBreakpointSiteList().FindByID(stop_value);
+        if (cur_site_sp && cur_site_sp->IsBreakpointAtThisSite(m_backstop_bkpt_id))
+        {
+            StackID cur_frame_zero_id = m_thread.GetStackFrameAtIndex(0)->GetStackID();
+            
+            if (cur_frame_zero_id == m_return_stack_id)
+            {
+                Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
+                if (log)
+                    log->PutCString ("ThreadPlanStepThrough hit backstop breakpoint.");
+                return true;
+            }
+        }
+    }
+    return false;
+}
+