1 files changed, 489 insertions, 0 deletions

diff --git a/source/Target/ThreadPlanStepOut.cpp b/source/Target/ThreadPlanStepOut.cpp
new file mode 100644
index 000000000000..ba529587437d
--- /dev/null
+++ b/source/Target/ThreadPlanStepOut.cpp
@@ -0,0 +1,489 @@
+//===-- ThreadPlanStepOut.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/ThreadPlanStepOut.h"
+
+// C Includes
+// C++ Includes
+// Other libraries and framework includes
+// Project includes
+#include "lldb/Breakpoint/Breakpoint.h"
+#include "lldb/lldb-private-log.h"
+#include "lldb/Core/Log.h"
+#include "lldb/Core/Value.h"
+#include "lldb/Core/ValueObjectConstResult.h"
+#include "lldb/Symbol/Block.h"
+#include "lldb/Symbol/Function.h"
+#include "lldb/Symbol/Type.h"
+#include "lldb/Target/Process.h"
+#include "lldb/Target/RegisterContext.h"
+#include "lldb/Target/StopInfo.h"
+#include "lldb/Target/Target.h"
+#include "lldb/Target/ThreadPlanStepOverRange.h"
+
+using namespace lldb;
+using namespace lldb_private;
+
+//----------------------------------------------------------------------
+// ThreadPlanStepOut: Step out of the current frame
+//----------------------------------------------------------------------
+ThreadPlanStepOut::ThreadPlanStepOut
+(
+    Thread &thread,
+    SymbolContext *context,
+    bool first_insn,
+    bool stop_others,
+    Vote stop_vote,
+    Vote run_vote,
+    uint32_t frame_idx
+) :
+    ThreadPlan (ThreadPlan::eKindStepOut, "Step out", thread, stop_vote, run_vote),
+    m_step_from_context (context),
+    m_step_from_insn (LLDB_INVALID_ADDRESS),
+    m_return_bp_id (LLDB_INVALID_BREAK_ID),
+    m_return_addr (LLDB_INVALID_ADDRESS),
+    m_first_insn (first_insn),
+    m_stop_others (stop_others),
+    m_step_through_inline_plan_sp(),
+    m_step_out_plan_sp (),
+    m_immediate_step_from_function(NULL)
+
+{
+    m_step_from_insn = m_thread.GetRegisterContext()->GetPC(0);
+
+    StackFrameSP return_frame_sp (m_thread.GetStackFrameAtIndex(frame_idx + 1));
+    StackFrameSP immediate_return_from_sp (m_thread.GetStackFrameAtIndex (frame_idx));
+    
+    if (!return_frame_sp || !immediate_return_from_sp)
+        return; // we can't do anything here.  ValidatePlan() will return false.
+    
+    m_step_out_to_id = return_frame_sp->GetStackID();
+    m_immediate_step_from_id = immediate_return_from_sp->GetStackID();
+    
+    StackID frame_zero_id = m_thread.GetStackFrameAtIndex(0)->GetStackID();
+
+    // If the frame directly below the one we are returning to is inlined, we have to be
+    // a little more careful.  It is non-trivial to determine the real "return code address" for
+    // an inlined frame, so we have to work our way to that frame and then step out.
+    if (immediate_return_from_sp && immediate_return_from_sp->IsInlined())
+    {
+        if (frame_idx > 0)
+        {
+            // First queue a plan that gets us to this inlined frame, and when we get there we'll queue a second
+            // plan that walks us out of this frame.
+            m_step_out_plan_sp.reset (new ThreadPlanStepOut(m_thread, 
+                                                            NULL, 
+                                                            false,
+                                                            stop_others, 
+                                                            eVoteNoOpinion, 
+                                                            eVoteNoOpinion, 
+                                                            frame_idx - 1));
+        }
+        else
+        {
+            // If we're already at the inlined frame we're stepping through, then just do that now.
+            QueueInlinedStepPlan(false);
+        }
+        
+    }
+    else if (return_frame_sp)
+    {
+        // Find the return address and set a breakpoint there:
+        // FIXME - can we do this more securely if we know first_insn?
+
+        m_return_addr = return_frame_sp->GetFrameCodeAddress().GetLoadAddress(&m_thread.GetProcess()->GetTarget());
+        
+        if (m_return_addr == LLDB_INVALID_ADDRESS)
+            return;
+        
+        Breakpoint *return_bp = m_thread.CalculateTarget()->CreateBreakpoint (m_return_addr, true).get();
+        if (return_bp != NULL)
+        {
+            return_bp->SetThreadID(m_thread.GetID());
+            m_return_bp_id = return_bp->GetID();
+            return_bp->SetBreakpointKind ("step-out");
+        }
+        
+        if (immediate_return_from_sp)
+        {
+            const SymbolContext &sc = immediate_return_from_sp->GetSymbolContext(eSymbolContextFunction);
+            if (sc.function)
+            {
+                m_immediate_step_from_function = sc.function; 
+            }
+        }
+    }
+
+}
+
+void
+ThreadPlanStepOut::DidPush()
+{
+    if (m_step_out_plan_sp)
+        m_thread.QueueThreadPlan(m_step_out_plan_sp, false);
+    else if (m_step_through_inline_plan_sp)
+        m_thread.QueueThreadPlan(m_step_through_inline_plan_sp, false);
+}
+
+ThreadPlanStepOut::~ThreadPlanStepOut ()
+{
+    if (m_return_bp_id != LLDB_INVALID_BREAK_ID)
+        m_thread.CalculateTarget()->RemoveBreakpointByID(m_return_bp_id);
+}
+
+void
+ThreadPlanStepOut::GetDescription (Stream *s, lldb::DescriptionLevel level)
+{
+    if (level == lldb::eDescriptionLevelBrief)
+        s->Printf ("step out");
+    else
+    {
+        if (m_step_out_plan_sp)
+            s->Printf ("Stepping out to inlined frame so we can walk through it.");
+        else if (m_step_through_inline_plan_sp)
+            s->Printf ("Stepping out by stepping through inlined function.");
+        else
+            s->Printf ("Stepping out from address 0x%" PRIx64 " to return address 0x%" PRIx64 " using breakpoint site %d",
+                       (uint64_t)m_step_from_insn,
+                       (uint64_t)m_return_addr,
+                       m_return_bp_id);
+    }
+}
+
+bool
+ThreadPlanStepOut::ValidatePlan (Stream *error)
+{
+    if (m_step_out_plan_sp)
+        return m_step_out_plan_sp->ValidatePlan (error);
+    else if (m_step_through_inline_plan_sp)
+        return m_step_through_inline_plan_sp->ValidatePlan (error);
+    else if (m_return_bp_id == LLDB_INVALID_BREAK_ID)
+    {
+        if (error)
+            error->PutCString("Could not create return address breakpoint.");
+        return false;
+    }
+    else
+        return true;
+}
+
+bool
+ThreadPlanStepOut::DoPlanExplainsStop (Event *event_ptr)
+{
+    // If one of our child plans just finished, then we do explain the stop.
+    if (m_step_out_plan_sp)
+    {
+        if (m_step_out_plan_sp->MischiefManaged())
+        {
+            // If this one is done, then we are all done.
+            CalculateReturnValue();
+            SetPlanComplete();
+            return true;
+        }
+        else
+            return false;
+    }
+    else if (m_step_through_inline_plan_sp)
+    {
+        if (m_step_through_inline_plan_sp->MischiefManaged())
+            return true;
+        else
+            return false;
+    }
+        
+    // We don't explain signals or breakpoints (breakpoints that handle stepping in or
+    // out will be handled by a child plan.
+    
+    StopInfoSP stop_info_sp = GetPrivateStopInfo ();
+    if (stop_info_sp)
+    {
+        StopReason reason = stop_info_sp->GetStopReason();
+        switch (reason)
+        {
+        case eStopReasonBreakpoint:
+        {
+            // If this is OUR breakpoint, we're fine, otherwise we don't know why this happened...
+            BreakpointSiteSP site_sp (m_thread.GetProcess()->GetBreakpointSiteList().FindByID (stop_info_sp->GetValue()));
+            if (site_sp && site_sp->IsBreakpointAtThisSite (m_return_bp_id))
+            {
+                bool done;
+                
+                StackID frame_zero_id = m_thread.GetStackFrameAtIndex(0)->GetStackID();
+                
+                if (m_step_out_to_id == frame_zero_id)
+                    done = true;
+                else if (m_step_out_to_id < frame_zero_id)
+                {
+                    // Either we stepped past the breakpoint, or the stack ID calculation
+                    // was incorrect and we should probably stop.
+                    done = true;
+                }
+                else
+                {
+                    if (m_immediate_step_from_id < frame_zero_id)
+                        done = true;
+                    else
+                        done = false;
+                }
+                    
+                if (done)
+                {
+                    CalculateReturnValue();
+                    SetPlanComplete();
+                }
+
+                // If there was only one owner, then we're done.  But if we also hit some
+                // user breakpoint on our way out, we should mark ourselves as done, but
+                // also not claim to explain the stop, since it is more important to report
+                // the user breakpoint than the step out completion.
+
+                if (site_sp->GetNumberOfOwners() == 1)
+                    return true;
+                
+            }
+            return false;
+        }
+        case eStopReasonWatchpoint:
+        case eStopReasonSignal:
+        case eStopReasonException:
+        case eStopReasonExec:
+        case eStopReasonThreadExiting:
+            return false;
+
+        default:
+            return true;
+        }
+    }
+    return true;
+}
+
+bool
+ThreadPlanStepOut::ShouldStop (Event *event_ptr)
+{
+        if (IsPlanComplete())
+            return true;
+        
+        bool done;
+        
+        StackID frame_zero_id = m_thread.GetStackFrameAtIndex(0)->GetStackID();
+        if (frame_zero_id < m_step_out_to_id)
+            done = false;
+        else
+            done = true;
+            
+        if (done)
+        {
+            CalculateReturnValue();
+            SetPlanComplete();
+            return true;
+        }
+        else
+        {
+            if (m_step_out_plan_sp)
+            {
+                if (m_step_out_plan_sp->MischiefManaged())
+                {
+                    // Now step through the inlined stack we are in:
+                    if (QueueInlinedStepPlan(true))
+                    {
+                        return false;
+                    }
+                    else
+                    {
+                        CalculateReturnValue();
+                        SetPlanComplete ();
+                        return true;
+                    }
+                }
+                else
+                    return m_step_out_plan_sp->ShouldStop(event_ptr);
+            }
+            else if (m_step_through_inline_plan_sp)
+            {
+                if (m_step_through_inline_plan_sp->MischiefManaged())
+                {
+                    // We don't calculate the return value here because we don't know how to.
+                    // But in case we had a return value sitting around from our process in
+                    // getting here, let's clear it out.
+                    m_return_valobj_sp.reset();
+                    SetPlanComplete();
+                    return true;
+                }
+                else
+                    return m_step_through_inline_plan_sp->ShouldStop(event_ptr);
+            }
+            else
+                return false;
+        }
+}
+
+bool
+ThreadPlanStepOut::StopOthers ()
+{
+    return m_stop_others;
+}
+
+StateType
+ThreadPlanStepOut::GetPlanRunState ()
+{
+    return eStateRunning;
+}
+
+bool
+ThreadPlanStepOut::DoWillResume (StateType resume_state, bool current_plan)
+{
+    if (m_step_out_plan_sp || m_step_through_inline_plan_sp)
+        return true;
+        
+    if (m_return_bp_id == LLDB_INVALID_BREAK_ID)
+        return false;
+
+    if (current_plan)
+    {
+        Breakpoint *return_bp = m_thread.CalculateTarget()->GetBreakpointByID(m_return_bp_id).get();
+        if (return_bp != NULL)
+            return_bp->SetEnabled (true);
+    }
+    return true;
+}
+
+bool
+ThreadPlanStepOut::WillStop ()
+{
+    if (m_return_bp_id != LLDB_INVALID_BREAK_ID)
+    {
+        Breakpoint *return_bp = m_thread.CalculateTarget()->GetBreakpointByID(m_return_bp_id).get();
+        if (return_bp != NULL)
+            return_bp->SetEnabled (false);
+    }
+    
+    return true;
+}
+
+bool
+ThreadPlanStepOut::MischiefManaged ()
+{
+    if (IsPlanComplete())
+    {
+        // Did I reach my breakpoint?  If so I'm done.
+        //
+        // I also check the stack depth, since if we've blown past the breakpoint for some
+        // reason and we're now stopping for some other reason altogether, then we're done
+        // with this step out operation.
+
+        Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
+        if (log)
+            log->Printf("Completed step out plan.");
+        if (m_return_bp_id != LLDB_INVALID_BREAK_ID)
+        {
+            m_thread.CalculateTarget()->RemoveBreakpointByID (m_return_bp_id);
+            m_return_bp_id = LLDB_INVALID_BREAK_ID;
+        }
+        
+        ThreadPlan::MischiefManaged ();
+        return true;
+    }
+    else
+    {
+        return false;
+    }
+}
+
+bool
+ThreadPlanStepOut::QueueInlinedStepPlan (bool queue_now)
+{
+    // Now figure out the range of this inlined block, and set up a "step through range"
+    // plan for that.  If we've been provided with a context, then use the block in that
+    // context.  
+    StackFrameSP immediate_return_from_sp (m_thread.GetStackFrameAtIndex (0));
+    if (!immediate_return_from_sp)
+        return false;
+        
+    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
+    if (log)
+    {   
+        StreamString s;
+        immediate_return_from_sp->Dump(&s, true, false);
+        log->Printf("Queuing inlined frame to step past: %s.", s.GetData());
+    }
+        
+    Block *from_block = immediate_return_from_sp->GetFrameBlock();
+    if (from_block)
+    {
+        Block *inlined_block = from_block->GetContainingInlinedBlock();
+        if (inlined_block)
+        {
+            size_t num_ranges = inlined_block->GetNumRanges();
+            AddressRange inline_range;
+            if (inlined_block->GetRangeAtIndex(0, inline_range))
+            {
+                SymbolContext inlined_sc;
+                inlined_block->CalculateSymbolContext(&inlined_sc);
+                inlined_sc.target_sp = GetTarget().shared_from_this();
+                RunMode run_mode = m_stop_others ? lldb::eOnlyThisThread : lldb::eAllThreads;
+                ThreadPlanStepOverRange *step_through_inline_plan_ptr = new ThreadPlanStepOverRange(m_thread, 
+                                                                                                    inline_range, 
+                                                                                                    inlined_sc, 
+                                                                                                    run_mode);
+                step_through_inline_plan_ptr->SetOkayToDiscard(true);                                                                                    
+                StreamString errors;
+                if (!step_through_inline_plan_ptr->ValidatePlan(&errors))
+                {
+                    //FIXME: Log this failure.
+                    delete step_through_inline_plan_ptr;
+                    return false;
+                }
+                
+                for (size_t i = 1; i < num_ranges; i++)
+                {
+                    if (inlined_block->GetRangeAtIndex (i, inline_range))
+                        step_through_inline_plan_ptr->AddRange (inline_range);
+                }
+                m_step_through_inline_plan_sp.reset (step_through_inline_plan_ptr);
+                if (queue_now)
+                    m_thread.QueueThreadPlan (m_step_through_inline_plan_sp, false);
+                return true;
+            }
+        }
+    }
+        
+    return false;
+}
+
+void
+ThreadPlanStepOut::CalculateReturnValue ()
+{
+    if (m_return_valobj_sp)
+        return;
+        
+    if (m_immediate_step_from_function != NULL)
+    {
+        ClangASTType return_clang_type = m_immediate_step_from_function->GetClangType().GetFunctionReturnType();
+        if (return_clang_type)
+        {
+            lldb::ABISP abi_sp = m_thread.GetProcess()->GetABI();
+            if (abi_sp)
+                m_return_valobj_sp = abi_sp->GetReturnValueObject(m_thread, return_clang_type);
+        }
+    }
+}
+
+bool
+ThreadPlanStepOut::IsPlanStale()
+{
+    // If we are still lower on the stack than the frame we are returning to, then
+    // there's something for us to do.  Otherwise, we're stale.
+    
+    StackID frame_zero_id = m_thread.GetStackFrameAtIndex(0)->GetStackID();
+    if (frame_zero_id < m_step_out_to_id)
+        return false;
+    else
+        return true;
+}
+