1 //===-- StackFrameList.cpp --------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "lldb/Target/StackFrameList.h"
11 
12 // C Includes
13 // C++ Includes
14 // Other libraries and framework includes
15 // Project includes
16 #include "lldb/Breakpoint/BreakpointLocation.h"
17 #include "lldb/Breakpoint/Breakpoint.h"
18 #include "lldb/Core/Log.h"
19 #include "lldb/Core/StreamFile.h"
20 #include "lldb/Core/SourceManager.h"
21 #include "lldb/Symbol/Block.h"
22 #include "lldb/Symbol/Function.h"
23 #include "lldb/Symbol/Symbol.h"
24 #include "lldb/Target/Process.h"
25 #include "lldb/Target/RegisterContext.h"
26 #include "lldb/Target/StackFrame.h"
27 #include "lldb/Target/StopInfo.h"
28 #include "lldb/Target/Target.h"
29 #include "lldb/Target/Thread.h"
30 #include "lldb/Target/Unwind.h"
31 
32 //#define DEBUG_STACK_FRAMES 1
33 
34 using namespace lldb;
35 using namespace lldb_private;
36 
37 //----------------------------------------------------------------------
38 // StackFrameList constructor
39 //----------------------------------------------------------------------
40 StackFrameList::StackFrameList
41 (
42     Thread &thread,
43     const lldb::StackFrameListSP &prev_frames_sp,
44     bool show_inline_frames
45 ) :
46     m_thread (thread),
47     m_prev_frames_sp (prev_frames_sp),
48     m_mutex (Mutex::eMutexTypeRecursive),
49     m_frames (),
50     m_selected_frame_idx (0),
51     m_concrete_frames_fetched (0),
52     m_current_inlined_depth (UINT32_MAX),
53     m_current_inlined_pc (LLDB_INVALID_ADDRESS),
54     m_show_inlined_frames (show_inline_frames)
55 {
56     if (prev_frames_sp)
57     {
58         m_current_inlined_depth = prev_frames_sp->m_current_inlined_depth;
59         m_current_inlined_pc =    prev_frames_sp->m_current_inlined_pc;
60     }
61 }
62 
63 //----------------------------------------------------------------------
64 // Destructor
65 //----------------------------------------------------------------------
66 StackFrameList::~StackFrameList()
67 {
68 }
69 
70 void
71 StackFrameList::CalculateCurrentInlinedDepth()
72 {
73     uint32_t cur_inlined_depth = GetCurrentInlinedDepth();
74     if (cur_inlined_depth == UINT32_MAX)
75     {
76         ResetCurrentInlinedDepth();
77     }
78 }
79 
80 uint32_t
81 StackFrameList::GetCurrentInlinedDepth ()
82 {
83     if (m_show_inlined_frames && m_current_inlined_pc != LLDB_INVALID_ADDRESS)
84     {
85         lldb::addr_t cur_pc = m_thread.GetRegisterContext()->GetPC();
86         if (cur_pc != m_current_inlined_pc)
87         {
88             m_current_inlined_pc = LLDB_INVALID_ADDRESS;
89             m_current_inlined_depth = UINT32_MAX;
90             LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
91             if (log && log->GetVerbose())
92                 log->Printf ("GetCurrentInlinedDepth: invalidating current inlined depth.\n");
93         }
94         return m_current_inlined_depth;
95     }
96     else
97     {
98         return UINT32_MAX;
99     }
100 }
101 
102 void
103 StackFrameList::ResetCurrentInlinedDepth ()
104 {
105     if (m_show_inlined_frames)
106     {
107         GetFramesUpTo(0);
108         if (!m_frames[0]->IsInlined())
109         {
110             m_current_inlined_depth = UINT32_MAX;
111             m_current_inlined_pc = LLDB_INVALID_ADDRESS;
112             LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
113             if (log && log->GetVerbose())
114                 log->Printf ("ResetCurrentInlinedDepth: Invalidating current inlined depth.\n");
115         }
116         else
117         {
118             // We only need to do something special about inlined blocks when we
119             // are at the beginning of an inlined function:
120             // FIXME: We probably also have to do something special if the PC is at the END
121             // of an inlined function, which coincides with the end of either its containing
122             // function or another inlined function.
123 
124             lldb::addr_t curr_pc = m_thread.GetRegisterContext()->GetPC();
125             Block *block_ptr = m_frames[0]->GetFrameBlock();
126             if (block_ptr)
127             {
128                 Address pc_as_address;
129                 pc_as_address.SetLoadAddress(curr_pc, &(m_thread.GetProcess()->GetTarget()));
130                 AddressRange containing_range;
131                 if (block_ptr->GetRangeContainingAddress(pc_as_address, containing_range))
132                 {
133                     if (pc_as_address == containing_range.GetBaseAddress())
134                     {
135                         // If we got here because of a breakpoint hit, then set the inlined depth depending on where
136                         // the breakpoint was set.
137                         // If we got here because of a crash, then set the inlined depth to the deepest most block.
138                         // Otherwise, we stopped here naturally as the result of a step, so set ourselves in the
139                         // containing frame of the whole set of nested inlines, so the user can then "virtually"
140                         // step into the frames one by one, or next over the whole mess.
141                         // Note: We don't have to handle being somewhere in the middle of the stack here, since
142                         // ResetCurrentInlinedDepth doesn't get called if there is a valid inlined depth set.
143                         StopInfoSP stop_info_sp = m_thread.GetStopInfo();
144                         if (stop_info_sp)
145                         {
146                             switch (stop_info_sp->GetStopReason())
147                             {
148                             case eStopReasonWatchpoint:
149                             case eStopReasonException:
150                             case eStopReasonSignal:
151                                 // In all these cases we want to stop in the deepest most frame.
152                                 m_current_inlined_pc = curr_pc;
153                                 m_current_inlined_depth = 0;
154                                 break;
155                             case eStopReasonBreakpoint:
156                                 {
157                                     // FIXME: Figure out what this break point is doing, and set the inline depth
158                                     // appropriately.  Be careful to take into account breakpoints that implement
159                                     // step over prologue, since that should do the default calculation.
160                                     // For now, if the breakpoints corresponding to this hit are all internal,
161                                     // I set the stop location to the top of the inlined stack, since that will make
162                                     // things like stepping over prologues work right.  But if there are any non-internal
163                                     // breakpoints I do to the bottom of the stack, since that was the old behavior.
164                                     uint32_t bp_site_id = stop_info_sp->GetValue();
165                                     BreakpointSiteSP bp_site_sp(m_thread.GetProcess()->GetBreakpointSiteList().FindByID(bp_site_id));
166                                     bool all_internal = true;
167                                     if (bp_site_sp)
168                                     {
169                                         uint32_t num_owners = bp_site_sp->GetNumberOfOwners();
170                                         for (uint32_t i = 0; i < num_owners; i++)
171                                         {
172                                             Breakpoint &bp_ref = bp_site_sp->GetOwnerAtIndex(i)->GetBreakpoint();
173                                             if (!bp_ref.IsInternal())
174                                             {
175                                                 all_internal = false;
176                                             }
177                                         }
178                                     }
179                                     if (!all_internal)
180                                     {
181                                         m_current_inlined_pc = curr_pc;
182                                         m_current_inlined_depth = 0;
183                                         break;
184                                     }
185                                 }
186                             default:
187                                 {
188                                     // Otherwise, we should set ourselves at the container of the inlining, so that the
189                                     // user can descend into them.
190                                     // So first we check whether we have more than one inlined block sharing this PC:
191                                     int num_inlined_functions = 0;
192 
193                                     for  (Block *container_ptr = block_ptr->GetInlinedParent();
194                                               container_ptr != NULL;
195                                               container_ptr = container_ptr->GetInlinedParent())
196                                     {
197                                         if (!container_ptr->GetRangeContainingAddress(pc_as_address, containing_range))
198                                             break;
199                                         if (pc_as_address != containing_range.GetBaseAddress())
200                                             break;
201 
202                                         num_inlined_functions++;
203                                     }
204                                     m_current_inlined_pc = curr_pc;
205                                     m_current_inlined_depth = num_inlined_functions + 1;
206                                     LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
207                                     if (log && log->GetVerbose())
208                                         log->Printf ("ResetCurrentInlinedDepth: setting inlined depth: %d 0x%llx.\n", m_current_inlined_depth, curr_pc);
209 
210                                 }
211                                 break;
212                             }
213                         }
214                     }
215                 }
216             }
217         }
218     }
219 }
220 
221 bool
222 StackFrameList::DecrementCurrentInlinedDepth ()
223 {
224     if (m_show_inlined_frames)
225     {
226         uint32_t current_inlined_depth = GetCurrentInlinedDepth();
227         if (current_inlined_depth != UINT32_MAX)
228         {
229             if (current_inlined_depth > 0)
230             {
231                 m_current_inlined_depth--;
232                 return true;
233             }
234         }
235     }
236     return false;
237 }
238 
239 void
240 StackFrameList::SetCurrentInlinedDepth (uint32_t new_depth)
241 {
242     m_current_inlined_depth = new_depth;
243     if (new_depth == UINT32_MAX)
244         m_current_inlined_pc = LLDB_INVALID_ADDRESS;
245     else
246         m_current_inlined_pc = m_thread.GetRegisterContext()->GetPC();
247 }
248 
249 void
250 StackFrameList::GetFramesUpTo(uint32_t end_idx)
251 {
252     // We've already gotten more frames than asked for, or we've already finished unwinding, return.
253     if (m_frames.size() > end_idx || GetAllFramesFetched())
254         return;
255 
256     Unwind *unwinder = m_thread.GetUnwinder ();
257 
258     if (m_show_inlined_frames)
259     {
260 #if defined (DEBUG_STACK_FRAMES)
261         StreamFile s(stdout, false);
262 #endif
263         // If we are hiding some frames from the outside world, we need to add those onto the total count of
264         // frames to fetch.  However, we don't need ot do that if end_idx is 0 since in that case we always
265         // get the first concrete frame and all the inlined frames below it...  And of course, if end_idx is
266         // UINT32_MAX that means get all, so just do that...
267 
268         uint32_t inlined_depth = 0;
269         if (end_idx > 0 && end_idx != UINT32_MAX)
270         {
271             inlined_depth = GetCurrentInlinedDepth();
272             if (inlined_depth != UINT32_MAX)
273             {
274                 if (end_idx > 0)
275                     end_idx += inlined_depth;
276             }
277         }
278 
279         StackFrameSP unwind_frame_sp;
280         do
281         {
282             uint32_t idx = m_concrete_frames_fetched++;
283             lldb::addr_t pc;
284             lldb::addr_t cfa;
285             if (idx == 0)
286             {
287                 // We might have already created frame zero, only create it
288                 // if we need to
289                 if (m_frames.empty())
290                 {
291                     m_thread.GetRegisterContext();
292                     assert (m_thread.m_reg_context_sp.get());
293 
294                     const bool success = unwinder->GetFrameInfoAtIndex(idx, cfa, pc);
295                     // There shouldn't be any way not to get the frame info for frame 0.
296                     // But if the unwinder can't make one, lets make one by hand with the
297                     // SP as the CFA and see if that gets any further.
298                     if (!success)
299                     {
300                         cfa = m_thread.GetRegisterContext()->GetSP();
301                         pc = m_thread.GetRegisterContext()->GetPC();
302                     }
303 
304                     unwind_frame_sp.reset (new StackFrame (m_thread.shared_from_this(),
305                                                            m_frames.size(),
306                                                            idx,
307                                                            m_thread.m_reg_context_sp,
308                                                            cfa,
309                                                            pc,
310                                                            NULL));
311                     m_frames.push_back (unwind_frame_sp);
312                 }
313                 else
314                 {
315                     unwind_frame_sp = m_frames.front();
316                     cfa = unwind_frame_sp->m_id.GetCallFrameAddress();
317                 }
318             }
319             else
320             {
321                 const bool success = unwinder->GetFrameInfoAtIndex(idx, cfa, pc);
322                 if (!success)
323                 {
324                     // We've gotten to the end of the stack.
325                     SetAllFramesFetched();
326                     break;
327                 }
328                 unwind_frame_sp.reset (new StackFrame (m_thread.shared_from_this(), m_frames.size(), idx, cfa, pc, NULL));
329                 m_frames.push_back (unwind_frame_sp);
330             }
331 
332             SymbolContext unwind_sc = unwind_frame_sp->GetSymbolContext (eSymbolContextBlock | eSymbolContextFunction);
333             Block *unwind_block = unwind_sc.block;
334             if (unwind_block)
335             {
336                 Address curr_frame_address (unwind_frame_sp->GetFrameCodeAddress());
337                 // Be sure to adjust the frame address to match the address
338                 // that was used to lookup the symbol context above. If we are
339                 // in the first concrete frame, then we lookup using the current
340                 // address, else we decrement the address by one to get the correct
341                 // location.
342                 if (idx > 0)
343                     curr_frame_address.Slide(-1);
344 
345                 SymbolContext next_frame_sc;
346                 Address next_frame_address;
347 
348                 while (unwind_sc.GetParentOfInlinedScope(curr_frame_address, next_frame_sc, next_frame_address))
349                 {
350                         StackFrameSP frame_sp(new StackFrame (m_thread.shared_from_this(),
351                                                               m_frames.size(),
352                                                               idx,
353                                                               unwind_frame_sp->GetRegisterContextSP (),
354                                                               cfa,
355                                                               next_frame_address,
356                                                               &next_frame_sc));
357 
358                         m_frames.push_back (frame_sp);
359                         unwind_sc = next_frame_sc;
360                         curr_frame_address = next_frame_address;
361                 }
362             }
363         } while (m_frames.size() - 1 < end_idx);
364 
365         // Don't try to merge till you've calculated all the frames in this stack.
366         if (GetAllFramesFetched() && m_prev_frames_sp)
367         {
368             StackFrameList *prev_frames = m_prev_frames_sp.get();
369             StackFrameList *curr_frames = this;
370 
371             //curr_frames->m_current_inlined_depth = prev_frames->m_current_inlined_depth;
372             //curr_frames->m_current_inlined_pc = prev_frames->m_current_inlined_pc;
373             //printf ("GetFramesUpTo: Copying current inlined depth: %d 0x%llx.\n", curr_frames->m_current_inlined_depth, curr_frames->m_current_inlined_pc);
374 
375 #if defined (DEBUG_STACK_FRAMES)
376             s.PutCString("\nprev_frames:\n");
377             prev_frames->Dump (&s);
378             s.PutCString("\ncurr_frames:\n");
379             curr_frames->Dump (&s);
380             s.EOL();
381 #endif
382             size_t curr_frame_num, prev_frame_num;
383 
384             for (curr_frame_num = curr_frames->m_frames.size(), prev_frame_num = prev_frames->m_frames.size();
385                  curr_frame_num > 0 && prev_frame_num > 0;
386                  --curr_frame_num, --prev_frame_num)
387             {
388                 const size_t curr_frame_idx = curr_frame_num-1;
389                 const size_t prev_frame_idx = prev_frame_num-1;
390                 StackFrameSP curr_frame_sp (curr_frames->m_frames[curr_frame_idx]);
391                 StackFrameSP prev_frame_sp (prev_frames->m_frames[prev_frame_idx]);
392 
393 #if defined (DEBUG_STACK_FRAMES)
394                 s.Printf("\n\nCurr frame #%u ", curr_frame_idx);
395                 if (curr_frame_sp)
396                     curr_frame_sp->Dump (&s, true, false);
397                 else
398                     s.PutCString("NULL");
399                 s.Printf("\nPrev frame #%u ", prev_frame_idx);
400                 if (prev_frame_sp)
401                     prev_frame_sp->Dump (&s, true, false);
402                 else
403                     s.PutCString("NULL");
404 #endif
405 
406                 StackFrame *curr_frame = curr_frame_sp.get();
407                 StackFrame *prev_frame = prev_frame_sp.get();
408 
409                 if (curr_frame == NULL || prev_frame == NULL)
410                     break;
411 
412                 // Check the stack ID to make sure they are equal
413                 if (curr_frame->GetStackID() != prev_frame->GetStackID())
414                     break;
415 
416                 prev_frame->UpdatePreviousFrameFromCurrentFrame (*curr_frame);
417                 // Now copy the fixed up previous frame into the current frames
418                 // so the pointer doesn't change
419                 m_frames[curr_frame_idx] = prev_frame_sp;
420                 //curr_frame->UpdateCurrentFrameFromPreviousFrame (*prev_frame);
421 
422 #if defined (DEBUG_STACK_FRAMES)
423                 s.Printf("\n    Copying previous frame to current frame");
424 #endif
425             }
426             // We are done with the old stack frame list, we can release it now
427             m_prev_frames_sp.reset();
428         }
429 
430 #if defined (DEBUG_STACK_FRAMES)
431             s.PutCString("\n\nNew frames:\n");
432             Dump (&s);
433             s.EOL();
434 #endif
435     }
436     else
437     {
438         if (end_idx < m_concrete_frames_fetched)
439             return;
440 
441         uint32_t num_frames = unwinder->GetFramesUpTo(end_idx);
442         if (num_frames <= end_idx + 1)
443         {
444             //Done unwinding.
445             m_concrete_frames_fetched = UINT32_MAX;
446         }
447         m_frames.resize(num_frames);
448     }
449 }
450 
451 uint32_t
452 StackFrameList::GetNumFrames (bool can_create)
453 {
454     Mutex::Locker locker (m_mutex);
455 
456     if (can_create)
457         GetFramesUpTo (UINT32_MAX);
458 
459     uint32_t inlined_depth = GetCurrentInlinedDepth();
460     if (inlined_depth == UINT32_MAX)
461         return m_frames.size();
462     else
463         return m_frames.size() - inlined_depth;
464 }
465 
466 void
467 StackFrameList::Dump (Stream *s)
468 {
469     if (s == NULL)
470         return;
471     Mutex::Locker locker (m_mutex);
472 
473     const_iterator pos, begin = m_frames.begin(), end = m_frames.end();
474     for (pos = begin; pos != end; ++pos)
475     {
476         StackFrame *frame = (*pos).get();
477         s->Printf("%p: ", frame);
478         if (frame)
479         {
480             frame->GetStackID().Dump (s);
481             frame->DumpUsingSettingsFormat (s);
482         }
483         else
484             s->Printf("frame #%u", (uint32_t)std::distance (begin, pos));
485         s->EOL();
486     }
487     s->EOL();
488 }
489 
490 StackFrameSP
491 StackFrameList::GetFrameAtIndex (uint32_t idx)
492 {
493     StackFrameSP frame_sp;
494     Mutex::Locker locker (m_mutex);
495     uint32_t inlined_depth = GetCurrentInlinedDepth();
496     if (inlined_depth != UINT32_MAX)
497         idx += inlined_depth;
498 
499     if (idx < m_frames.size())
500         frame_sp = m_frames[idx];
501 
502     if (frame_sp)
503         return frame_sp;
504 
505         // GetFramesUpTo will fill m_frames with as many frames as you asked for,
506         // if there are that many.  If there weren't then you asked for too many
507         // frames.
508         GetFramesUpTo (idx);
509         if (idx < m_frames.size())
510         {
511             if (m_show_inlined_frames)
512             {
513                 // When inline frames are enabled we actually create all the frames in GetFramesUpTo.
514                 frame_sp = m_frames[idx];
515             }
516             else
517             {
518                 Unwind *unwinder = m_thread.GetUnwinder ();
519                 if (unwinder)
520                 {
521                     addr_t pc, cfa;
522                     if (unwinder->GetFrameInfoAtIndex(idx, cfa, pc))
523                     {
524                         frame_sp.reset (new StackFrame (m_thread.shared_from_this(), idx, idx, cfa, pc, NULL));
525 
526                         Function *function = frame_sp->GetSymbolContext (eSymbolContextFunction).function;
527                         if (function)
528                         {
529                             // When we aren't showing inline functions we always use
530                             // the top most function block as the scope.
531                             frame_sp->SetSymbolContextScope (&function->GetBlock(false));
532                         }
533                         else
534                         {
535                             // Set the symbol scope from the symbol regardless if it is NULL or valid.
536                             frame_sp->SetSymbolContextScope (frame_sp->GetSymbolContext (eSymbolContextSymbol).symbol);
537                         }
538                         SetFrameAtIndex(idx, frame_sp);
539                     }
540                 }
541             }
542         }
543     return frame_sp;
544 }
545 
546 StackFrameSP
547 StackFrameList::GetFrameWithConcreteFrameIndex (uint32_t unwind_idx)
548 {
549     // First try assuming the unwind index is the same as the frame index. The
550     // unwind index is always greater than or equal to the frame index, so it
551     // is a good place to start. If we have inlined frames we might have 5
552     // concrete frames (frame unwind indexes go from 0-4), but we might have 15
553     // frames after we make all the inlined frames. Most of the time the unwind
554     // frame index (or the concrete frame index) is the same as the frame index.
555     uint32_t frame_idx = unwind_idx;
556     StackFrameSP frame_sp (GetFrameAtIndex (frame_idx));
557     while (frame_sp)
558     {
559         if (frame_sp->GetFrameIndex() == unwind_idx)
560             break;
561         frame_sp = GetFrameAtIndex (++frame_idx);
562     }
563     return frame_sp;
564 }
565 
566 StackFrameSP
567 StackFrameList::GetFrameWithStackID (const StackID &stack_id)
568 {
569     uint32_t frame_idx = 0;
570     StackFrameSP frame_sp;
571     do
572     {
573         frame_sp = GetFrameAtIndex (frame_idx);
574         if (frame_sp && frame_sp->GetStackID() == stack_id)
575             break;
576         frame_idx++;
577     }
578     while (frame_sp);
579     return frame_sp;
580 }
581 
582 bool
583 StackFrameList::SetFrameAtIndex (uint32_t idx, StackFrameSP &frame_sp)
584 {
585     if (idx >= m_frames.size())
586         m_frames.resize(idx + 1);
587     // Make sure allocation succeeded by checking bounds again
588     if (idx < m_frames.size())
589     {
590         m_frames[idx] = frame_sp;
591         return true;
592     }
593     return false;   // resize failed, out of memory?
594 }
595 
596 uint32_t
597 StackFrameList::GetSelectedFrameIndex () const
598 {
599     Mutex::Locker locker (m_mutex);
600     return m_selected_frame_idx;
601 }
602 
603 
604 uint32_t
605 StackFrameList::SetSelectedFrame (lldb_private::StackFrame *frame)
606 {
607     Mutex::Locker locker (m_mutex);
608     const_iterator pos;
609     const_iterator begin = m_frames.begin();
610     const_iterator end = m_frames.end();
611     m_selected_frame_idx = 0;
612     for (pos = begin; pos != end; ++pos)
613     {
614         if (pos->get() == frame)
615         {
616             m_selected_frame_idx = std::distance (begin, pos);
617             uint32_t inlined_depth = GetCurrentInlinedDepth();
618             if (inlined_depth != UINT32_MAX)
619                 m_selected_frame_idx -= inlined_depth;
620             break;
621         }
622     }
623     SetDefaultFileAndLineToSelectedFrame();
624     return m_selected_frame_idx;
625 }
626 
627 // Mark a stack frame as the current frame using the frame index
628 bool
629 StackFrameList::SetSelectedFrameByIndex (uint32_t idx)
630 {
631     Mutex::Locker locker (m_mutex);
632     StackFrameSP frame_sp (GetFrameAtIndex (idx));
633     if (frame_sp)
634     {
635         SetSelectedFrame(frame_sp.get());
636         return true;
637     }
638     else
639         return false;
640 }
641 
642 void
643 StackFrameList::SetDefaultFileAndLineToSelectedFrame()
644 {
645     if (m_thread.GetID() == m_thread.GetProcess()->GetThreadList().GetSelectedThread()->GetID())
646     {
647         StackFrameSP frame_sp (GetFrameAtIndex (GetSelectedFrameIndex()));
648         if (frame_sp)
649         {
650             SymbolContext sc = frame_sp->GetSymbolContext(eSymbolContextLineEntry);
651             if (sc.line_entry.file)
652                 m_thread.CalculateTarget()->GetSourceManager().SetDefaultFileAndLine (sc.line_entry.file,
653                                                                                             sc.line_entry.line);
654         }
655     }
656 }
657 
658 // The thread has been run, reset the number stack frames to zero so we can
659 // determine how many frames we have lazily.
660 void
661 StackFrameList::Clear ()
662 {
663     Mutex::Locker locker (m_mutex);
664     m_frames.clear();
665     m_concrete_frames_fetched = 0;
666 }
667 
668 void
669 StackFrameList::InvalidateFrames (uint32_t start_idx)
670 {
671     Mutex::Locker locker (m_mutex);
672     if (m_show_inlined_frames)
673     {
674         Clear();
675     }
676     else
677     {
678         const size_t num_frames = m_frames.size();
679         while (start_idx < num_frames)
680         {
681             m_frames[start_idx].reset();
682             ++start_idx;
683         }
684     }
685 }
686 
687 void
688 StackFrameList::Merge (std::auto_ptr<StackFrameList>& curr_ap, lldb::StackFrameListSP& prev_sp)
689 {
690     Mutex::Locker curr_locker (curr_ap.get() ? &curr_ap->m_mutex : NULL);
691     Mutex::Locker prev_locker (prev_sp.get() ? &prev_sp->m_mutex : NULL);
692 
693 #if defined (DEBUG_STACK_FRAMES)
694     StreamFile s(stdout, false);
695     s.PutCString("\n\nStackFrameList::Merge():\nPrev:\n");
696     if (prev_sp.get())
697         prev_sp->Dump (&s);
698     else
699         s.PutCString ("NULL");
700     s.PutCString("\nCurr:\n");
701     if (curr_ap.get())
702         curr_ap->Dump (&s);
703     else
704         s.PutCString ("NULL");
705     s.EOL();
706 #endif
707 
708     if (curr_ap.get() == NULL || curr_ap->GetNumFrames (false) == 0)
709     {
710 #if defined (DEBUG_STACK_FRAMES)
711         s.PutCString("No current frames, leave previous frames alone...\n");
712 #endif
713         curr_ap.release();
714         return;
715     }
716 
717     if (prev_sp.get() == NULL || prev_sp->GetNumFrames (false) == 0)
718     {
719 #if defined (DEBUG_STACK_FRAMES)
720         s.PutCString("No previous frames, so use current frames...\n");
721 #endif
722         // We either don't have any previous frames, or since we have more than
723         // one current frames it means we have all the frames and can safely
724         // replace our previous frames.
725         prev_sp.reset (curr_ap.release());
726         return;
727     }
728 
729     const uint32_t num_curr_frames = curr_ap->GetNumFrames (false);
730 
731     if (num_curr_frames > 1)
732     {
733 #if defined (DEBUG_STACK_FRAMES)
734         s.PutCString("We have more than one current frame, so use current frames...\n");
735 #endif
736         // We have more than one current frames it means we have all the frames
737         // and can safely replace our previous frames.
738         prev_sp.reset (curr_ap.release());
739 
740 #if defined (DEBUG_STACK_FRAMES)
741         s.PutCString("\nMerged:\n");
742         prev_sp->Dump (&s);
743 #endif
744         return;
745     }
746 
747     StackFrameSP prev_frame_zero_sp(prev_sp->GetFrameAtIndex (0));
748     StackFrameSP curr_frame_zero_sp(curr_ap->GetFrameAtIndex (0));
749     StackID curr_stack_id (curr_frame_zero_sp->GetStackID());
750     StackID prev_stack_id (prev_frame_zero_sp->GetStackID());
751 
752 #if defined (DEBUG_STACK_FRAMES)
753     const uint32_t num_prev_frames = prev_sp->GetNumFrames (false);
754     s.Printf("\n%u previous frames with one current frame\n", num_prev_frames);
755 #endif
756 
757     // We have only a single current frame
758     // Our previous stack frames only had a single frame as well...
759     if (curr_stack_id == prev_stack_id)
760     {
761 #if defined (DEBUG_STACK_FRAMES)
762         s.Printf("\nPrevious frame #0 is same as current frame #0, merge the cached data\n");
763 #endif
764 
765         curr_frame_zero_sp->UpdateCurrentFrameFromPreviousFrame (*prev_frame_zero_sp);
766 //        prev_frame_zero_sp->UpdatePreviousFrameFromCurrentFrame (*curr_frame_zero_sp);
767 //        prev_sp->SetFrameAtIndex (0, prev_frame_zero_sp);
768     }
769     else if (curr_stack_id < prev_stack_id)
770     {
771 #if defined (DEBUG_STACK_FRAMES)
772         s.Printf("\nCurrent frame #0 has a stack ID that is less than the previous frame #0, insert current frame zero in front of previous\n");
773 #endif
774         prev_sp->m_frames.insert (prev_sp->m_frames.begin(), curr_frame_zero_sp);
775     }
776 
777     curr_ap.release();
778 
779 #if defined (DEBUG_STACK_FRAMES)
780     s.PutCString("\nMerged:\n");
781     prev_sp->Dump (&s);
782 #endif
783 
784 
785 }
786 
787 lldb::StackFrameSP
788 StackFrameList::GetStackFrameSPForStackFramePtr (StackFrame *stack_frame_ptr)
789 {
790     const_iterator pos;
791     const_iterator begin = m_frames.begin();
792     const_iterator end = m_frames.end();
793     lldb::StackFrameSP ret_sp;
794 
795     for (pos = begin; pos != end; ++pos)
796     {
797         if (pos->get() == stack_frame_ptr)
798         {
799             ret_sp = (*pos);
800             break;
801         }
802     }
803     return ret_sp;
804 }
805 
806 size_t
807 StackFrameList::GetStatus (Stream& strm,
808                            uint32_t first_frame,
809                            uint32_t num_frames,
810                            bool show_frame_info,
811                            uint32_t num_frames_with_source)
812 {
813     size_t num_frames_displayed = 0;
814 
815     if (num_frames == 0)
816         return 0;
817 
818     StackFrameSP frame_sp;
819     uint32_t frame_idx = 0;
820     uint32_t last_frame;
821 
822     // Don't let the last frame wrap around...
823     if (num_frames == UINT32_MAX)
824         last_frame = UINT32_MAX;
825     else
826         last_frame = first_frame + num_frames;
827 
828     for (frame_idx = first_frame; frame_idx < last_frame; ++frame_idx)
829     {
830         frame_sp = GetFrameAtIndex(frame_idx);
831         if (frame_sp.get() == NULL)
832             break;
833 
834         if (!frame_sp->GetStatus (strm,
835                                   show_frame_info,
836                                   num_frames_with_source > (first_frame - frame_idx)))
837             break;
838         ++num_frames_displayed;
839     }
840 
841     strm.IndentLess();
842     return num_frames_displayed;
843 }
844 
845