1 //===-- StackFrame.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/StackFrame.h"
11 
12 // C Includes
13 // C++ Includes
14 // Other libraries and framework includes
15 // Project includes
16 #include "lldb/Core/Module.h"
17 #include "lldb/Core/Debugger.h"
18 #include "lldb/Core/Disassembler.h"
19 #include "lldb/Core/Value.h"
20 #include "lldb/Core/ValueObjectVariable.h"
21 #include "lldb/Core/ValueObjectConstResult.h"
22 #include "lldb/Symbol/Function.h"
23 #include "lldb/Symbol/VariableList.h"
24 #include "lldb/Target/ExecutionContext.h"
25 #include "lldb/Target/Process.h"
26 #include "lldb/Target/RegisterContext.h"
27 #include "lldb/Target/Target.h"
28 #include "lldb/Target/Thread.h"
29 
30 using namespace lldb;
31 using namespace lldb_private;
32 
33 // The first bits in the flags are reserved for the SymbolContext::Scope bits
34 // so we know if we have tried to look up information in our internal symbol
35 // context (m_sc) already.
36 #define RESOLVED_FRAME_CODE_ADDR        (uint32_t(eSymbolContextEverything + 1))
37 #define RESOLVED_FRAME_ID_SYMBOL_SCOPE  (RESOLVED_FRAME_CODE_ADDR << 1)
38 #define GOT_FRAME_BASE                  (RESOLVED_FRAME_ID_SYMBOL_SCOPE << 1)
39 #define RESOLVED_VARIABLES              (GOT_FRAME_BASE << 1)
40 #define RESOLVED_GLOBAL_VARIABLES       (RESOLVED_VARIABLES << 1)
41 
42 StackFrame::StackFrame
43 (
44     lldb::user_id_t frame_idx,
45     lldb::user_id_t unwind_frame_index,
46     Thread &thread,
47     lldb::addr_t cfa,
48     lldb::addr_t pc,
49     const SymbolContext *sc_ptr
50 ) :
51     m_frame_index (frame_idx),
52     m_concrete_frame_index (unwind_frame_index),
53     m_thread (thread),
54     m_reg_context_sp (),
55     m_id (pc, cfa, NULL),
56     m_frame_code_addr (NULL, pc),
57     m_sc (),
58     m_flags (),
59     m_frame_base (),
60     m_frame_base_error (),
61     m_variable_list_sp (),
62     m_variable_list_value_objects ()
63 {
64     if (sc_ptr != NULL)
65     {
66         m_sc = *sc_ptr;
67         m_flags.Set(m_sc.GetResolvedMask ());
68     }
69 }
70 
71 StackFrame::StackFrame
72 (
73     lldb::user_id_t frame_idx,
74     lldb::user_id_t unwind_frame_index,
75     Thread &thread,
76     const RegisterContextSP &reg_context_sp,
77     lldb::addr_t cfa,
78     lldb::addr_t pc,
79     const SymbolContext *sc_ptr
80 ) :
81     m_frame_index (frame_idx),
82     m_concrete_frame_index (unwind_frame_index),
83     m_thread (thread),
84     m_reg_context_sp (reg_context_sp),
85     m_id (pc, cfa, NULL),
86     m_frame_code_addr (NULL, pc),
87     m_sc (),
88     m_flags (),
89     m_frame_base (),
90     m_frame_base_error (),
91     m_variable_list_sp (),
92     m_variable_list_value_objects ()
93 {
94     if (sc_ptr != NULL)
95     {
96         m_sc = *sc_ptr;
97         m_flags.Set(m_sc.GetResolvedMask ());
98     }
99 
100     if (reg_context_sp && !m_sc.target_sp)
101     {
102         m_sc.target_sp = reg_context_sp->GetThread().GetProcess().GetTarget().GetSP();
103         m_flags.Set (eSymbolContextTarget);
104     }
105 }
106 
107 StackFrame::StackFrame
108 (
109     lldb::user_id_t frame_idx,
110     lldb::user_id_t unwind_frame_index,
111     Thread &thread,
112     const RegisterContextSP &reg_context_sp,
113     lldb::addr_t cfa,
114     const Address& pc_addr,
115     const SymbolContext *sc_ptr
116 ) :
117     m_frame_index (frame_idx),
118     m_concrete_frame_index (unwind_frame_index),
119     m_thread (thread),
120     m_reg_context_sp (reg_context_sp),
121     m_id (pc_addr.GetLoadAddress (&thread.GetProcess().GetTarget()), cfa, NULL),
122     m_frame_code_addr (pc_addr),
123     m_sc (),
124     m_flags (),
125     m_frame_base (),
126     m_frame_base_error (),
127     m_variable_list_sp (),
128     m_variable_list_value_objects ()
129 {
130     if (sc_ptr != NULL)
131     {
132         m_sc = *sc_ptr;
133         m_flags.Set(m_sc.GetResolvedMask ());
134     }
135 
136     if (m_sc.target_sp.get() == NULL && reg_context_sp)
137     {
138         m_sc.target_sp = reg_context_sp->GetThread().GetProcess().GetTarget().GetSP();
139         m_flags.Set (eSymbolContextTarget);
140     }
141 
142     Module *pc_module = pc_addr.GetModule();
143     if (m_sc.module_sp.get() == NULL || m_sc.module_sp.get() != pc_module)
144     {
145         if (pc_module)
146         {
147             m_sc.module_sp = pc_module->GetSP();
148             m_flags.Set (eSymbolContextModule);
149         }
150         else
151         {
152             m_sc.module_sp.reset();
153         }
154 
155     }
156 }
157 
158 
159 //----------------------------------------------------------------------
160 // Destructor
161 //----------------------------------------------------------------------
162 StackFrame::~StackFrame()
163 {
164 }
165 
166 StackID&
167 StackFrame::GetStackID()
168 {
169     // Make sure we have resolved the StackID object's symbol context scope if
170     // we already haven't looked it up.
171 
172     if (m_flags.IsClear (RESOLVED_FRAME_ID_SYMBOL_SCOPE))
173     {
174         if (m_id.GetSymbolContextScope ())
175         {
176             // We already have a symbol context scope, we just don't have our
177             // flag bit set.
178             m_flags.Set (RESOLVED_FRAME_ID_SYMBOL_SCOPE);
179         }
180         else
181         {
182             // Calculate the frame block and use this for the stack ID symbol
183             // context scope if we have one.
184             SymbolContextScope *scope = GetFrameBlock ();
185             if (scope == NULL)
186             {
187                 // We don't have a block, so use the symbol
188                 if (m_flags.IsClear (eSymbolContextSymbol))
189                     GetSymbolContext (eSymbolContextSymbol);
190 
191                 // It is ok if m_sc.symbol is NULL here
192                 scope = m_sc.symbol;
193             }
194             // Set the symbol context scope (the accessor will set the
195             // RESOLVED_FRAME_ID_SYMBOL_SCOPE bit in m_flags).
196             SetSymbolContextScope (scope);
197         }
198     }
199     return m_id;
200 }
201 
202 void
203 StackFrame::SetSymbolContextScope (SymbolContextScope *symbol_scope)
204 {
205     m_flags.Set (RESOLVED_FRAME_ID_SYMBOL_SCOPE);
206     m_id.SetSymbolContextScope (symbol_scope);
207 }
208 
209 Address&
210 StackFrame::GetFrameCodeAddress()
211 {
212     if (m_flags.IsClear(RESOLVED_FRAME_CODE_ADDR) && !m_frame_code_addr.IsSectionOffset())
213     {
214         m_flags.Set (RESOLVED_FRAME_CODE_ADDR);
215 
216         // Resolve the PC into a temporary address because if ResolveLoadAddress
217         // fails to resolve the address, it will clear the address object...
218         Address resolved_pc;
219         if (m_thread.GetProcess().GetTarget().GetSectionLoadList().ResolveLoadAddress(m_frame_code_addr.GetOffset(), resolved_pc))
220         {
221             m_frame_code_addr = resolved_pc;
222             const Section *section = m_frame_code_addr.GetSection();
223             if (section)
224             {
225                 Module *module = section->GetModule();
226                 if (module)
227                 {
228                     m_sc.module_sp = module->GetSP();
229                     if (m_sc.module_sp)
230                         m_flags.Set(eSymbolContextModule);
231                 }
232             }
233         }
234     }
235     return m_frame_code_addr;
236 }
237 
238 void
239 StackFrame::ChangePC (addr_t pc)
240 {
241     m_frame_code_addr.SetOffset(pc);
242     m_frame_code_addr.SetSection(NULL);
243     m_sc.Clear();
244     m_flags.Reset(0);
245     m_thread.ClearStackFrames ();
246 }
247 
248 const char *
249 StackFrame::Disassemble ()
250 {
251     if (m_disassembly.GetSize() == 0)
252     {
253         ExecutionContext exe_ctx;
254         CalculateExecutionContext(exe_ctx);
255         Target &target = m_thread.GetProcess().GetTarget();
256         Disassembler::Disassemble (target.GetDebugger(),
257                                    target.GetArchitecture(),
258                                    exe_ctx,
259                                    0,
260                                    false,
261                                    m_disassembly);
262         if (m_disassembly.GetSize() == 0)
263             return NULL;
264     }
265     return m_disassembly.GetData();
266 }
267 
268 Block *
269 StackFrame::GetFrameBlock ()
270 {
271     if (m_sc.block == NULL && m_flags.IsClear (eSymbolContextBlock))
272         GetSymbolContext (eSymbolContextBlock);
273 
274     if (m_sc.block)
275     {
276         Block *inline_block = m_sc.block->GetContainingInlinedBlock();
277         if (inline_block)
278         {
279             // Use the block with the inlined function info
280             // as the frame block we want this frame to have only the variables
281             // for the inlined function and its non-inlined block child blocks.
282             return inline_block;
283         }
284         else
285         {
286             // This block is not contained withing any inlined function blocks
287             // with so we want to use the top most function block.
288             return &m_sc.function->GetBlock (false);
289         }
290     }
291     return NULL;
292 }
293 
294 //----------------------------------------------------------------------
295 // Get the symbol context if we already haven't done so by resolving the
296 // PC address as much as possible. This way when we pass around a
297 // StackFrame object, everyone will have as much information as
298 // possible and no one will ever have to look things up manually.
299 //----------------------------------------------------------------------
300 const SymbolContext&
301 StackFrame::GetSymbolContext (uint32_t resolve_scope)
302 {
303     // Copy our internal symbol context into "sc".
304     if ((m_flags.Get() & resolve_scope) != resolve_scope)
305     {
306         // Resolve our PC to section offset if we haven't alreday done so
307         // and if we don't have a module. The resolved address section will
308         // contain the module to which it belongs
309         if (!m_sc.module_sp && m_flags.IsClear(RESOLVED_FRAME_CODE_ADDR))
310             GetFrameCodeAddress();
311 
312         // If this is not frame zero, then we need to subtract 1 from the PC
313         // value when doing address lookups since the PC will be on the
314         // instruction following the function call instruction...
315 
316         Address lookup_addr(GetFrameCodeAddress());
317         if (m_frame_index > 0 && lookup_addr.IsValid())
318         {
319             addr_t offset = lookup_addr.GetOffset();
320             if (offset > 0)
321                 lookup_addr.SetOffset(offset - 1);
322         }
323 
324 
325         uint32_t resolved = 0;
326         if (m_sc.module_sp)
327         {
328             // We have something in our stack frame symbol context, lets check
329             // if we haven't already tried to lookup one of those things. If we
330             // haven't then we will do the query.
331 
332             uint32_t actual_resolve_scope = 0;
333 
334             if (resolve_scope & eSymbolContextCompUnit)
335             {
336                 if (m_flags.IsClear (eSymbolContextCompUnit))
337                 {
338                     if (m_sc.comp_unit)
339                         resolved |= eSymbolContextCompUnit;
340                     else
341                         actual_resolve_scope |= eSymbolContextCompUnit;
342                 }
343             }
344 
345             if (resolve_scope & eSymbolContextFunction)
346             {
347                 if (m_flags.IsClear (eSymbolContextFunction))
348                 {
349                     if (m_sc.function)
350                         resolved |= eSymbolContextFunction;
351                     else
352                         actual_resolve_scope |= eSymbolContextFunction;
353                 }
354             }
355 
356             if (resolve_scope & eSymbolContextBlock)
357             {
358                 if (m_flags.IsClear (eSymbolContextBlock))
359                 {
360                     if (m_sc.block)
361                         resolved |= eSymbolContextBlock;
362                     else
363                         actual_resolve_scope |= eSymbolContextBlock;
364                 }
365             }
366 
367             if (resolve_scope & eSymbolContextSymbol)
368             {
369                 if (m_flags.IsClear (eSymbolContextSymbol))
370                 {
371                     if (m_sc.symbol)
372                         resolved |= eSymbolContextSymbol;
373                     else
374                         actual_resolve_scope |= eSymbolContextSymbol;
375                 }
376             }
377 
378             if (resolve_scope & eSymbolContextLineEntry)
379             {
380                 if (m_flags.IsClear (eSymbolContextLineEntry))
381                 {
382                     if (m_sc.line_entry.IsValid())
383                         resolved |= eSymbolContextLineEntry;
384                     else
385                         actual_resolve_scope |= eSymbolContextLineEntry;
386                 }
387             }
388 
389             if (actual_resolve_scope)
390             {
391                 // We might be resolving less information than what is already
392                 // in our current symbol context so resolve into a temporary
393                 // symbol context "sc" so we don't clear out data we have
394                 // already found in "m_sc"
395                 SymbolContext sc;
396                 // Set flags that indicate what we have tried to resolve
397                 resolved |= m_sc.module_sp->ResolveSymbolContextForAddress (lookup_addr, actual_resolve_scope, sc);
398                 // Only replace what we didn't already have as we may have
399                 // information for an inlined function scope that won't match
400                 // what a standard lookup by address would match
401                 if ((resolved & eSymbolContextCompUnit)  && m_sc.comp_unit == NULL)
402                     m_sc.comp_unit = sc.comp_unit;
403                 if ((resolved & eSymbolContextFunction)  && m_sc.function == NULL)
404                     m_sc.function = sc.function;
405                 if ((resolved & eSymbolContextBlock)     && m_sc.block == NULL)
406                     m_sc.block = sc.block;
407                 if ((resolved & eSymbolContextSymbol)    && m_sc.symbol == NULL)
408                     m_sc.symbol = sc.symbol;
409                 if ((resolved & eSymbolContextLineEntry) && !m_sc.line_entry.IsValid())
410                     m_sc.line_entry = sc.line_entry;
411 
412             }
413         }
414         else
415         {
416             // If we don't have a module, then we can't have the compile unit,
417             // function, block, line entry or symbol, so we can safely call
418             // ResolveSymbolContextForAddress with our symbol context member m_sc.
419             resolved |= m_thread.GetProcess().GetTarget().GetImages().ResolveSymbolContextForAddress (lookup_addr, resolve_scope, m_sc);
420         }
421 
422         // If the target was requested add that:
423         if (m_sc.target_sp.get() == NULL)
424         {
425             m_sc.target_sp = CalculateProcess()->GetTarget().GetSP();
426             if (m_sc.target_sp)
427                 resolved |= eSymbolContextTarget;
428         }
429 
430         // Update our internal flags so we remember what we have tried to locate so
431         // we don't have to keep trying when more calls to this function are made.
432         // We might have dug up more information that was requested (for example
433         // if we were asked to only get the block, we will have gotten the
434         // compile unit, and function) so set any additional bits that we resolved
435         m_flags.Set (resolve_scope | resolved);
436     }
437 
438     // Return the symbol context with everything that was possible to resolve
439     // resolved.
440     return m_sc;
441 }
442 
443 
444 VariableList *
445 StackFrame::GetVariableList (bool get_file_globals)
446 {
447     if (m_flags.IsClear(RESOLVED_VARIABLES))
448     {
449         m_flags.Set(RESOLVED_VARIABLES);
450 
451         Block *frame_block = GetFrameBlock();
452 
453         if (frame_block)
454         {
455             const bool get_child_variables = true;
456             const bool can_create = true;
457             m_variable_list_sp = frame_block->GetVariableList (get_child_variables, can_create);
458         }
459     }
460 
461     if (m_flags.IsClear(RESOLVED_GLOBAL_VARIABLES) &&
462         get_file_globals)
463     {
464         m_flags.Set(RESOLVED_GLOBAL_VARIABLES);
465 
466         if (m_flags.IsClear (eSymbolContextCompUnit))
467             GetSymbolContext (eSymbolContextCompUnit);
468 
469         if (m_sc.comp_unit)
470         {
471             VariableListSP global_variable_list_sp (m_sc.comp_unit->GetVariableList(true));
472             if (m_variable_list_sp)
473                 m_variable_list_sp->AddVariables (global_variable_list_sp.get());
474             else
475                 m_variable_list_sp = global_variable_list_sp;
476         }
477     }
478 
479     return m_variable_list_sp.get();
480 }
481 
482 ValueObjectSP
483 StackFrame::GetValueForVariableExpressionPath (const char *var_expr_cstr, bool check_ptr_vs_member, Error &error)
484 {
485 
486     if (var_expr_cstr && var_expr_cstr[0])
487     {
488         error.Clear();
489         bool deref = false;
490         bool address_of = false;
491         ValueObjectSP valobj_sp;
492         const bool get_file_globals = true;
493         VariableList *variable_list = GetVariableList (get_file_globals);
494 
495         if (variable_list)
496         {
497             // If first character is a '*', then show pointer contents
498             const char *var_expr = var_expr_cstr;
499             if (var_expr[0] == '*')
500             {
501                 deref = true;
502                 var_expr++; // Skip the '*'
503             }
504             else if (var_expr[0] == '&')
505             {
506                 address_of = true;
507                 var_expr++; // Skip the '&'
508             }
509 
510             std::string var_path (var_expr);
511             size_t separator_idx = var_path.find_first_of(".-[=+~|&^%#@!/?,<>{}");
512             StreamString var_expr_path_strm;
513 
514             ConstString name_const_string;
515             if (separator_idx == std::string::npos)
516                 name_const_string.SetCString (var_path.c_str());
517             else
518                 name_const_string.SetCStringWithLength (var_path.c_str(), separator_idx);
519 
520             VariableSP var_sp (variable_list->FindVariable(name_const_string));
521             if (var_sp)
522             {
523                 valobj_sp = GetValueObjectForFrameVariable (var_sp);
524 
525                 var_path.erase (0, name_const_string.GetLength ());
526                 // We are dumping at least one child
527                 while (separator_idx != std::string::npos)
528                 {
529                     // Calculate the next separator index ahead of time
530                     ValueObjectSP child_valobj_sp;
531                     const char separator_type = var_path[0];
532                     switch (separator_type)
533                     {
534 
535                     case '-':
536                         if (var_path.size() >= 2 && var_path[1] != '>')
537                             return ValueObjectSP();
538 
539                         var_path.erase (0, 1); // Remove the '-'
540                         // Fall through
541                     case '.':
542                         {
543                             const bool expr_is_ptr = var_path[0] == '>';
544 
545                             var_path.erase (0, 1); // Remove the '.' or '>'
546                             separator_idx = var_path.find_first_of(".-[");
547                             ConstString child_name;
548                             if (separator_idx == std::string::npos)
549                                 child_name.SetCString (var_path.c_str());
550                             else
551                                 child_name.SetCStringWithLength(var_path.c_str(), separator_idx);
552 
553                             if (check_ptr_vs_member)
554                             {
555                                 // We either have a pointer type and need to verify
556                                 // valobj_sp is a pointer, or we have a member of a
557                                 // class/union/struct being accessed with the . syntax
558                                 // and need to verify we don't have a pointer.
559                                 const bool actual_is_ptr = valobj_sp->IsPointerType ();
560 
561                                 if (actual_is_ptr != expr_is_ptr)
562                                 {
563                                     // Incorrect use of "." with a pointer, or "->" with
564                                     // a class/union/struct instance or reference.
565                                     valobj_sp->GetExpressionPath (var_expr_path_strm, false);
566                                     if (actual_is_ptr)
567                                         error.SetErrorStringWithFormat ("\"%s\" is a pointer and . was used to attempt to access \"%s\". Did you mean \"%s->%s\"?",
568                                                                         var_expr_path_strm.GetString().c_str(),
569                                                                         child_name.GetCString(),
570                                                                         var_expr_path_strm.GetString().c_str(),
571                                                                         var_path.c_str());
572                                     else
573                                         error.SetErrorStringWithFormat ("\"%s\" is not a pointer and -> was used to attempt to access \"%s\". Did you mean \"%s.%s\"?",
574                                                                         var_expr_path_strm.GetString().c_str(),
575                                                                         child_name.GetCString(),
576                                                                         var_expr_path_strm.GetString().c_str(),
577                                                                         var_path.c_str());
578                                     return ValueObjectSP();
579                                 }
580                             }
581 
582                             child_valobj_sp = valobj_sp->GetChildMemberWithName (child_name, true);
583                             if (!child_valobj_sp)
584                             {
585                                 // No child member with name "child_name"
586                                 valobj_sp->GetExpressionPath (var_expr_path_strm, false);
587                                 if (child_name)
588                                 {
589                                     error.SetErrorStringWithFormat ("\"%s\" is not a member of \"(%s) %s\"",
590                                                                     child_name.GetCString(),
591                                                                     valobj_sp->GetTypeName().AsCString("<invalid type>"),
592                                                                     var_expr_path_strm.GetString().c_str());
593                                 }
594                                 else
595                                 {
596                                     error.SetErrorStringWithFormat ("incomplete expression path after \"%s\" in \"%s\"",
597                                                                     var_expr_path_strm.GetString().c_str(),
598                                                                     var_expr_cstr);
599                                 }
600 
601                                 return ValueObjectSP();
602                             }
603                             // Remove the child name from the path
604                             var_path.erase(0, child_name.GetLength());
605                         }
606                         break;
607 
608                     case '[':
609                         // Array member access, or treating pointer as an array
610                         if (var_path.size() > 2) // Need at least two brackets and a number
611                         {
612                             char *end = NULL;
613                             int32_t child_index = ::strtol (&var_path[1], &end, 0);
614                             if (end && *end == ']')
615                             {
616 
617                                 if (valobj_sp->IsPointerType ())
618                                 {
619                                     child_valobj_sp = valobj_sp->GetSyntheticArrayMemberFromPointer (child_index, true);
620                                     if (!child_valobj_sp)
621                                     {
622                                         valobj_sp->GetExpressionPath (var_expr_path_strm, false);
623                                         error.SetErrorStringWithFormat ("failed to use pointer as array for index %i for \"(%s) %s\"",
624                                                                         child_index,
625                                                                         valobj_sp->GetTypeName().AsCString("<invalid type>"),
626                                                                         var_expr_path_strm.GetString().c_str());
627                                     }
628                                 }
629                                 else if (ClangASTContext::IsArrayType (valobj_sp->GetClangType(), NULL, NULL))
630                                 {
631                                     child_valobj_sp = valobj_sp->GetChildAtIndex (child_index, true);
632                                     if (!child_valobj_sp)
633                                     {
634                                         valobj_sp->GetExpressionPath (var_expr_path_strm, false);
635                                         error.SetErrorStringWithFormat ("array index %i is not valid for \"(%s) %s\"",
636                                                                         child_index,
637                                                                         valobj_sp->GetTypeName().AsCString("<invalid type>"),
638                                                                         var_expr_path_strm.GetString().c_str());
639                                     }
640                                 }
641                                 else
642                                 {
643                                     valobj_sp->GetExpressionPath (var_expr_path_strm, false);
644                                     error.SetErrorStringWithFormat ("\"(%s) %s\" is not an array type",
645                                                                     valobj_sp->GetTypeName().AsCString("<invalid type>"),
646                                                                     var_expr_path_strm.GetString().c_str());
647                                 }
648 
649                                 if (!child_valobj_sp)
650                                 {
651                                     // Invalid array index...
652                                     return ValueObjectSP();
653                                 }
654 
655                                 // Erase the array member specification '[%i]' where
656                                 // %i is the array index
657                                 var_path.erase(0, (end - var_path.c_str()) + 1);
658                                 separator_idx = var_path.find_first_of(".-[");
659 
660                                 // Break out early from the switch since we were
661                                 // able to find the child member
662                                 break;
663                             }
664                         }
665                         return ValueObjectSP();
666 
667                     default:
668                         // Failure...
669                         {
670                             valobj_sp->GetExpressionPath (var_expr_path_strm, false);
671                             error.SetErrorStringWithFormat ("unexpected char '%c' encountered after \"%s\" in \"%s\"",
672                                                             separator_type,
673                                                             var_expr_path_strm.GetString().c_str(),
674                                                             var_path.c_str());
675 
676                             return ValueObjectSP();
677                         }
678                     }
679 
680                     if (child_valobj_sp)
681                         valobj_sp = child_valobj_sp;
682 
683                     if (var_path.empty())
684                         break;
685 
686                 }
687                 if (valobj_sp)
688                 {
689                     if (deref)
690                     {
691                         ValueObjectSP deref_valobj_sp (valobj_sp->Dereference(error));
692                         valobj_sp = deref_valobj_sp;
693                     }
694                     else if (address_of)
695                     {
696                         ValueObjectSP address_of_valobj_sp (valobj_sp->AddressOf(error));
697                         valobj_sp = address_of_valobj_sp;
698                     }
699                 }
700                 return valobj_sp;
701             }
702             else
703             {
704                 error.SetErrorStringWithFormat("no variable named '%s' found in this frame", name_const_string.GetCString());
705             }
706         }
707     }
708     else
709     {
710         error.SetErrorStringWithFormat("invalid variable path '%s'", var_expr_cstr);
711     }
712     return ValueObjectSP();
713 }
714 
715 bool
716 StackFrame::GetFrameBaseValue (Scalar &frame_base, Error *error_ptr)
717 {
718     if (m_flags.IsClear(GOT_FRAME_BASE))
719     {
720         if (m_sc.function)
721         {
722             m_frame_base.Clear();
723             m_frame_base_error.Clear();
724 
725             m_flags.Set(GOT_FRAME_BASE);
726             ExecutionContext exe_ctx (&m_thread.GetProcess(), &m_thread, this);
727             Value expr_value;
728             addr_t loclist_base_addr = LLDB_INVALID_ADDRESS;
729             if (m_sc.function->GetFrameBaseExpression().IsLocationList())
730                 loclist_base_addr = m_sc.function->GetAddressRange().GetBaseAddress().GetLoadAddress (&m_thread.GetProcess().GetTarget());
731 
732             if (m_sc.function->GetFrameBaseExpression().Evaluate(&exe_ctx, NULL, NULL, loclist_base_addr, NULL, expr_value, &m_frame_base_error) == false)
733             {
734                 // We should really have an error if evaluate returns, but in case
735                 // we don't, lets set the error to something at least.
736                 if (m_frame_base_error.Success())
737                     m_frame_base_error.SetErrorString("Evaluation of the frame base expression failed.");
738             }
739             else
740             {
741                 m_frame_base = expr_value.ResolveValue(&exe_ctx, NULL);
742             }
743         }
744         else
745         {
746             m_frame_base_error.SetErrorString ("No function in symbol context.");
747         }
748     }
749 
750     if (m_frame_base_error.Success())
751         frame_base = m_frame_base;
752 
753     if (error_ptr)
754         *error_ptr = m_frame_base_error;
755     return m_frame_base_error.Success();
756 }
757 
758 RegisterContextSP
759 StackFrame::GetRegisterContext ()
760 {
761     if (!m_reg_context_sp)
762         m_reg_context_sp = m_thread.CreateRegisterContextForFrame (this);
763     return m_reg_context_sp;
764 }
765 
766 bool
767 StackFrame::HasDebugInformation ()
768 {
769     GetSymbolContext (eSymbolContextLineEntry);
770     return m_sc.line_entry.IsValid();
771 }
772 
773 
774 ValueObjectSP
775 StackFrame::GetValueObjectForFrameVariable (const VariableSP &variable_sp)
776 {
777     ValueObjectSP valobj_sp;
778     VariableList *var_list = GetVariableList (true);
779     if (var_list)
780     {
781         // Make sure the variable is a frame variable
782         const uint32_t var_idx = var_list->FindIndexForVariable (variable_sp.get());
783         const uint32_t num_variables = var_list->GetSize();
784         if (var_idx < num_variables)
785         {
786             valobj_sp = m_variable_list_value_objects.GetValueObjectAtIndex (var_idx);
787             if (valobj_sp.get() == NULL)
788             {
789                 if (m_variable_list_value_objects.GetSize() < num_variables)
790                     m_variable_list_value_objects.Resize(num_variables);
791                 valobj_sp.reset (new ValueObjectVariable (variable_sp));
792                 m_variable_list_value_objects.SetValueObjectAtIndex (var_idx, valobj_sp);
793             }
794         }
795     }
796     return valobj_sp;
797 }
798 
799 ValueObjectSP
800 StackFrame::TrackGlobalVariable (const VariableSP &variable_sp)
801 {
802     // Check to make sure we aren't already tracking this variable?
803     ValueObjectSP valobj_sp (GetValueObjectForFrameVariable (variable_sp));
804     if (!valobj_sp)
805     {
806         // We aren't already tracking this global
807         VariableList *var_list = GetVariableList (true);
808         // If this frame has no variables, create a new list
809         if (var_list == NULL)
810             m_variable_list_sp.reset (new VariableList());
811 
812         // Add the global/static variable to this frame
813         m_variable_list_sp->AddVariable (variable_sp);
814 
815         // Now make a value object for it so we can track its changes
816         valobj_sp = GetValueObjectForFrameVariable (variable_sp);
817     }
818     return valobj_sp;
819 }
820 
821 bool
822 StackFrame::IsInlined ()
823 {
824     if (m_sc.block == NULL)
825         GetSymbolContext (eSymbolContextBlock);
826     if (m_sc.block)
827         return m_sc.block->GetContainingInlinedBlock() != NULL;
828     return false;
829 }
830 
831 Target *
832 StackFrame::CalculateTarget ()
833 {
834     return m_thread.CalculateTarget();
835 }
836 
837 Process *
838 StackFrame::CalculateProcess ()
839 {
840     return m_thread.CalculateProcess();
841 }
842 
843 Thread *
844 StackFrame::CalculateThread ()
845 {
846     return &m_thread;
847 }
848 
849 StackFrame *
850 StackFrame::CalculateStackFrame ()
851 {
852     return this;
853 }
854 
855 
856 void
857 StackFrame::CalculateExecutionContext (ExecutionContext &exe_ctx)
858 {
859     m_thread.CalculateExecutionContext (exe_ctx);
860     exe_ctx.frame = this;
861 }
862 
863 void
864 StackFrame::DumpUsingSettingsFormat (Stream *strm)
865 {
866     if (strm == NULL)
867         return;
868 
869     GetSymbolContext(eSymbolContextEverything);
870     ExecutionContext exe_ctx;
871     CalculateExecutionContext(exe_ctx);
872     const char *end = NULL;
873     StreamString s;
874     const char *frame_format = m_thread.GetProcess().GetTarget().GetDebugger().GetFrameFormat();
875     if (frame_format && Debugger::FormatPrompt (frame_format, &m_sc, &exe_ctx, NULL, s, &end))
876     {
877         strm->Write(s.GetData(), s.GetSize());
878     }
879     else
880     {
881         Dump (strm, true, false);
882         strm->EOL();
883     }
884 }
885 
886 void
887 StackFrame::Dump (Stream *strm, bool show_frame_index, bool show_fullpaths)
888 {
889     if (strm == NULL)
890         return;
891 
892     if (show_frame_index)
893         strm->Printf("frame #%u: ", m_frame_index);
894     strm->Printf("0x%0*llx ", m_thread.GetProcess().GetAddressByteSize() * 2, GetFrameCodeAddress().GetLoadAddress(&m_thread.GetProcess().GetTarget()));
895     GetSymbolContext(eSymbolContextEverything);
896     const bool show_module = true;
897     const bool show_inline = true;
898     m_sc.DumpStopContext(strm, &m_thread.GetProcess(), GetFrameCodeAddress(), show_fullpaths, show_module, show_inline);
899 }
900 
901 void
902 StackFrame::UpdateCurrentFrameFromPreviousFrame (StackFrame &prev_frame)
903 {
904     assert (GetStackID() == prev_frame.GetStackID());    // TODO: remove this after some testing
905     m_variable_list_sp = prev_frame.m_variable_list_sp;
906     m_variable_list_value_objects.Swap (prev_frame.m_variable_list_value_objects);
907     if (!m_disassembly.GetString().empty())
908         m_disassembly.GetString().swap (m_disassembly.GetString());
909 }
910 
911 
912 void
913 StackFrame::UpdatePreviousFrameFromCurrentFrame (StackFrame &curr_frame)
914 {
915     assert (GetStackID() == curr_frame.GetStackID());        // TODO: remove this after some testing
916     m_id.SetPC (curr_frame.m_id.GetPC());       // Update the Stack ID PC value
917     assert (&m_thread == &curr_frame.m_thread);
918     m_frame_index = curr_frame.m_frame_index;
919     m_concrete_frame_index = curr_frame.m_concrete_frame_index;
920     m_reg_context_sp = curr_frame.m_reg_context_sp;
921     m_frame_code_addr = curr_frame.m_frame_code_addr;
922     assert (m_sc.target_sp.get() == NULL || curr_frame.m_sc.target_sp.get() == NULL || m_sc.target_sp.get() == curr_frame.m_sc.target_sp.get());
923     assert (m_sc.module_sp.get() == NULL || curr_frame.m_sc.module_sp.get() == NULL || m_sc.module_sp.get() == curr_frame.m_sc.module_sp.get());
924     assert (m_sc.comp_unit == NULL || curr_frame.m_sc.comp_unit == NULL || m_sc.comp_unit == curr_frame.m_sc.comp_unit);
925     assert (m_sc.function == NULL || curr_frame.m_sc.function == NULL || m_sc.function == curr_frame.m_sc.function);
926     m_sc = curr_frame.m_sc;
927     m_flags.Clear(GOT_FRAME_BASE | eSymbolContextEverything);
928     m_flags.Set (m_sc.GetResolvedMask());
929     m_frame_base.Clear();
930     m_frame_base_error.Clear();
931 }
932 
933 
934 bool
935 StackFrame::HasCachedData () const
936 {
937     if (m_variable_list_sp.get())
938         return true;
939     if (m_variable_list_value_objects.GetSize() > 0)
940         return true;
941     if (!m_disassembly.GetString().empty())
942         return true;
943     return false;
944 }
945 
946 lldb::StackFrameSP
947 StackFrame::GetSP ()
948 {
949     return m_thread.GetStackFrameSPForStackFramePtr (this);
950 }