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 // C Includes
11 // C++ Includes
12 // Other libraries and framework includes
13 // Project includes
14 #include "lldb/Target/StackFrame.h"
15 #include "lldb/Core/Debugger.h"
16 #include "lldb/Core/Disassembler.h"
17 #include "lldb/Core/FormatEntity.h"
18 #include "lldb/Core/Mangled.h"
19 #include "lldb/Core/Module.h"
20 #include "lldb/Core/Value.h"
21 #include "lldb/Core/ValueObjectConstResult.h"
22 #include "lldb/Core/ValueObjectMemory.h"
23 #include "lldb/Core/ValueObjectVariable.h"
24 #include "lldb/Symbol/CompileUnit.h"
25 #include "lldb/Symbol/Function.h"
26 #include "lldb/Symbol/Symbol.h"
27 #include "lldb/Symbol/SymbolContextScope.h"
28 #include "lldb/Symbol/Type.h"
29 #include "lldb/Symbol/VariableList.h"
30 #include "lldb/Target/ABI.h"
31 #include "lldb/Target/ExecutionContext.h"
32 #include "lldb/Target/Process.h"
33 #include "lldb/Target/RegisterContext.h"
34 #include "lldb/Target/Target.h"
35 #include "lldb/Target/Thread.h"
36 
37 using namespace lldb;
38 using namespace lldb_private;
39 
40 // The first bits in the flags are reserved for the SymbolContext::Scope bits
41 // so we know if we have tried to look up information in our internal symbol
42 // context (m_sc) already.
43 #define RESOLVED_FRAME_CODE_ADDR (uint32_t(eSymbolContextEverything + 1))
44 #define RESOLVED_FRAME_ID_SYMBOL_SCOPE (RESOLVED_FRAME_CODE_ADDR << 1)
45 #define GOT_FRAME_BASE (RESOLVED_FRAME_ID_SYMBOL_SCOPE << 1)
46 #define RESOLVED_VARIABLES (GOT_FRAME_BASE << 1)
47 #define RESOLVED_GLOBAL_VARIABLES (RESOLVED_VARIABLES << 1)
48 
49 StackFrame::StackFrame(const ThreadSP &thread_sp, user_id_t frame_idx,
50                        user_id_t unwind_frame_index, addr_t cfa,
51                        bool cfa_is_valid, addr_t pc, uint32_t stop_id,
52                        bool stop_id_is_valid, bool is_history_frame,
53                        const SymbolContext *sc_ptr)
54     : m_thread_wp(thread_sp), m_frame_index(frame_idx),
55       m_concrete_frame_index(unwind_frame_index), m_reg_context_sp(),
56       m_id(pc, cfa, nullptr), m_frame_code_addr(pc), m_sc(), m_flags(),
57       m_frame_base(), m_frame_base_error(), m_cfa_is_valid(cfa_is_valid),
58       m_stop_id(stop_id), m_stop_id_is_valid(stop_id_is_valid),
59       m_is_history_frame(is_history_frame), m_variable_list_sp(),
60       m_variable_list_value_objects(), m_disassembly(), m_mutex() {
61   // If we don't have a CFA value, use the frame index for our StackID so that
62   // recursive
63   // functions properly aren't confused with one another on a history stack.
64   if (m_is_history_frame && !m_cfa_is_valid) {
65     m_id.SetCFA(m_frame_index);
66   }
67 
68   if (sc_ptr != nullptr) {
69     m_sc = *sc_ptr;
70     m_flags.Set(m_sc.GetResolvedMask());
71   }
72 }
73 
74 StackFrame::StackFrame(const ThreadSP &thread_sp, user_id_t frame_idx,
75                        user_id_t unwind_frame_index,
76                        const RegisterContextSP &reg_context_sp, addr_t cfa,
77                        addr_t pc, const SymbolContext *sc_ptr)
78     : m_thread_wp(thread_sp), m_frame_index(frame_idx),
79       m_concrete_frame_index(unwind_frame_index),
80       m_reg_context_sp(reg_context_sp), m_id(pc, cfa, nullptr),
81       m_frame_code_addr(pc), m_sc(), m_flags(), m_frame_base(),
82       m_frame_base_error(), m_cfa_is_valid(true), m_stop_id(0),
83       m_stop_id_is_valid(false), m_is_history_frame(false),
84       m_variable_list_sp(), m_variable_list_value_objects(), m_disassembly(),
85       m_mutex() {
86   if (sc_ptr != nullptr) {
87     m_sc = *sc_ptr;
88     m_flags.Set(m_sc.GetResolvedMask());
89   }
90 
91   if (reg_context_sp && !m_sc.target_sp) {
92     m_sc.target_sp = reg_context_sp->CalculateTarget();
93     if (m_sc.target_sp)
94       m_flags.Set(eSymbolContextTarget);
95   }
96 }
97 
98 StackFrame::StackFrame(const ThreadSP &thread_sp, user_id_t frame_idx,
99                        user_id_t unwind_frame_index,
100                        const RegisterContextSP &reg_context_sp, addr_t cfa,
101                        const Address &pc_addr, const SymbolContext *sc_ptr)
102     : m_thread_wp(thread_sp), m_frame_index(frame_idx),
103       m_concrete_frame_index(unwind_frame_index),
104       m_reg_context_sp(reg_context_sp),
105       m_id(pc_addr.GetLoadAddress(thread_sp->CalculateTarget().get()), cfa,
106            nullptr),
107       m_frame_code_addr(pc_addr), m_sc(), m_flags(), m_frame_base(),
108       m_frame_base_error(), m_cfa_is_valid(true), m_stop_id(0),
109       m_stop_id_is_valid(false), m_is_history_frame(false),
110       m_variable_list_sp(), m_variable_list_value_objects(), m_disassembly(),
111       m_mutex() {
112   if (sc_ptr != nullptr) {
113     m_sc = *sc_ptr;
114     m_flags.Set(m_sc.GetResolvedMask());
115   }
116 
117   if (!m_sc.target_sp && reg_context_sp) {
118     m_sc.target_sp = reg_context_sp->CalculateTarget();
119     if (m_sc.target_sp)
120       m_flags.Set(eSymbolContextTarget);
121   }
122 
123   ModuleSP pc_module_sp(pc_addr.GetModule());
124   if (!m_sc.module_sp || m_sc.module_sp != pc_module_sp) {
125     if (pc_module_sp) {
126       m_sc.module_sp = pc_module_sp;
127       m_flags.Set(eSymbolContextModule);
128     } else {
129       m_sc.module_sp.reset();
130     }
131   }
132 }
133 
134 StackFrame::~StackFrame() = default;
135 
136 StackID &StackFrame::GetStackID() {
137   std::lock_guard<std::recursive_mutex> guard(m_mutex);
138   // Make sure we have resolved the StackID object's symbol context scope if
139   // we already haven't looked it up.
140 
141   if (m_flags.IsClear(RESOLVED_FRAME_ID_SYMBOL_SCOPE)) {
142     if (m_id.GetSymbolContextScope()) {
143       // We already have a symbol context scope, we just don't have our
144       // flag bit set.
145       m_flags.Set(RESOLVED_FRAME_ID_SYMBOL_SCOPE);
146     } else {
147       // Calculate the frame block and use this for the stack ID symbol
148       // context scope if we have one.
149       SymbolContextScope *scope = GetFrameBlock();
150       if (scope == nullptr) {
151         // We don't have a block, so use the symbol
152         if (m_flags.IsClear(eSymbolContextSymbol))
153           GetSymbolContext(eSymbolContextSymbol);
154 
155         // It is ok if m_sc.symbol is nullptr here
156         scope = m_sc.symbol;
157       }
158       // Set the symbol context scope (the accessor will set the
159       // RESOLVED_FRAME_ID_SYMBOL_SCOPE bit in m_flags).
160       SetSymbolContextScope(scope);
161     }
162   }
163   return m_id;
164 }
165 
166 uint32_t StackFrame::GetFrameIndex() const {
167   ThreadSP thread_sp = GetThread();
168   if (thread_sp)
169     return thread_sp->GetStackFrameList()->GetVisibleStackFrameIndex(
170         m_frame_index);
171   else
172     return m_frame_index;
173 }
174 
175 void StackFrame::SetSymbolContextScope(SymbolContextScope *symbol_scope) {
176   std::lock_guard<std::recursive_mutex> guard(m_mutex);
177   m_flags.Set(RESOLVED_FRAME_ID_SYMBOL_SCOPE);
178   m_id.SetSymbolContextScope(symbol_scope);
179 }
180 
181 const Address &StackFrame::GetFrameCodeAddress() {
182   std::lock_guard<std::recursive_mutex> guard(m_mutex);
183   if (m_flags.IsClear(RESOLVED_FRAME_CODE_ADDR) &&
184       !m_frame_code_addr.IsSectionOffset()) {
185     m_flags.Set(RESOLVED_FRAME_CODE_ADDR);
186 
187     // Resolve the PC into a temporary address because if ResolveLoadAddress
188     // fails to resolve the address, it will clear the address object...
189     ThreadSP thread_sp(GetThread());
190     if (thread_sp) {
191       TargetSP target_sp(thread_sp->CalculateTarget());
192       if (target_sp) {
193         if (m_frame_code_addr.SetOpcodeLoadAddress(
194                 m_frame_code_addr.GetOffset(), target_sp.get(),
195                 eAddressClassCode)) {
196           ModuleSP module_sp(m_frame_code_addr.GetModule());
197           if (module_sp) {
198             m_sc.module_sp = module_sp;
199             m_flags.Set(eSymbolContextModule);
200           }
201         }
202       }
203     }
204   }
205   return m_frame_code_addr;
206 }
207 
208 bool StackFrame::ChangePC(addr_t pc) {
209   std::lock_guard<std::recursive_mutex> guard(m_mutex);
210   // We can't change the pc value of a history stack frame - it is immutable.
211   if (m_is_history_frame)
212     return false;
213   m_frame_code_addr.SetRawAddress(pc);
214   m_sc.Clear(false);
215   m_flags.Reset(0);
216   ThreadSP thread_sp(GetThread());
217   if (thread_sp)
218     thread_sp->ClearStackFrames();
219   return true;
220 }
221 
222 const char *StackFrame::Disassemble() {
223   std::lock_guard<std::recursive_mutex> guard(m_mutex);
224   if (m_disassembly.GetSize() == 0) {
225     ExecutionContext exe_ctx(shared_from_this());
226     Target *target = exe_ctx.GetTargetPtr();
227     if (target) {
228       const char *plugin_name = nullptr;
229       const char *flavor = nullptr;
230       Disassembler::Disassemble(target->GetDebugger(),
231                                 target->GetArchitecture(), plugin_name, flavor,
232                                 exe_ctx, 0, false, 0, 0, m_disassembly);
233     }
234     if (m_disassembly.GetSize() == 0)
235       return nullptr;
236   }
237   return m_disassembly.GetData();
238 }
239 
240 Block *StackFrame::GetFrameBlock() {
241   if (m_sc.block == nullptr && m_flags.IsClear(eSymbolContextBlock))
242     GetSymbolContext(eSymbolContextBlock);
243 
244   if (m_sc.block) {
245     Block *inline_block = m_sc.block->GetContainingInlinedBlock();
246     if (inline_block) {
247       // Use the block with the inlined function info
248       // as the frame block we want this frame to have only the variables
249       // for the inlined function and its non-inlined block child blocks.
250       return inline_block;
251     } else {
252       // This block is not contained within any inlined function blocks
253       // with so we want to use the top most function block.
254       return &m_sc.function->GetBlock(false);
255     }
256   }
257   return nullptr;
258 }
259 
260 //----------------------------------------------------------------------
261 // Get the symbol context if we already haven't done so by resolving the
262 // PC address as much as possible. This way when we pass around a
263 // StackFrame object, everyone will have as much information as
264 // possible and no one will ever have to look things up manually.
265 //----------------------------------------------------------------------
266 const SymbolContext &StackFrame::GetSymbolContext(uint32_t resolve_scope) {
267   std::lock_guard<std::recursive_mutex> guard(m_mutex);
268   // Copy our internal symbol context into "sc".
269   if ((m_flags.Get() & resolve_scope) != resolve_scope) {
270     uint32_t resolved = 0;
271 
272     // If the target was requested add that:
273     if (!m_sc.target_sp) {
274       m_sc.target_sp = CalculateTarget();
275       if (m_sc.target_sp)
276         resolved |= eSymbolContextTarget;
277     }
278 
279     // Resolve our PC to section offset if we haven't already done so
280     // and if we don't have a module. The resolved address section will
281     // contain the module to which it belongs
282     if (!m_sc.module_sp && m_flags.IsClear(RESOLVED_FRAME_CODE_ADDR))
283       GetFrameCodeAddress();
284 
285     // If this is not frame zero, then we need to subtract 1 from the PC
286     // value when doing address lookups since the PC will be on the
287     // instruction following the function call instruction...
288 
289     Address lookup_addr(GetFrameCodeAddress());
290     if (m_frame_index > 0 && lookup_addr.IsValid()) {
291       addr_t offset = lookup_addr.GetOffset();
292       if (offset > 0) {
293         lookup_addr.SetOffset(offset - 1);
294 
295       } else {
296         // lookup_addr is the start of a section.  We need
297         // do the math on the actual load address and re-compute
298         // the section.  We're working with a 'noreturn' function
299         // at the end of a section.
300         ThreadSP thread_sp(GetThread());
301         if (thread_sp) {
302           TargetSP target_sp(thread_sp->CalculateTarget());
303           if (target_sp) {
304             addr_t addr_minus_one =
305                 lookup_addr.GetLoadAddress(target_sp.get()) - 1;
306             lookup_addr.SetLoadAddress(addr_minus_one, target_sp.get());
307           } else {
308             lookup_addr.SetOffset(offset - 1);
309           }
310         }
311       }
312     }
313 
314     if (m_sc.module_sp) {
315       // We have something in our stack frame symbol context, lets check
316       // if we haven't already tried to lookup one of those things. If we
317       // haven't then we will do the query.
318 
319       uint32_t actual_resolve_scope = 0;
320 
321       if (resolve_scope & eSymbolContextCompUnit) {
322         if (m_flags.IsClear(eSymbolContextCompUnit)) {
323           if (m_sc.comp_unit)
324             resolved |= eSymbolContextCompUnit;
325           else
326             actual_resolve_scope |= eSymbolContextCompUnit;
327         }
328       }
329 
330       if (resolve_scope & eSymbolContextFunction) {
331         if (m_flags.IsClear(eSymbolContextFunction)) {
332           if (m_sc.function)
333             resolved |= eSymbolContextFunction;
334           else
335             actual_resolve_scope |= eSymbolContextFunction;
336         }
337       }
338 
339       if (resolve_scope & eSymbolContextBlock) {
340         if (m_flags.IsClear(eSymbolContextBlock)) {
341           if (m_sc.block)
342             resolved |= eSymbolContextBlock;
343           else
344             actual_resolve_scope |= eSymbolContextBlock;
345         }
346       }
347 
348       if (resolve_scope & eSymbolContextSymbol) {
349         if (m_flags.IsClear(eSymbolContextSymbol)) {
350           if (m_sc.symbol)
351             resolved |= eSymbolContextSymbol;
352           else
353             actual_resolve_scope |= eSymbolContextSymbol;
354         }
355       }
356 
357       if (resolve_scope & eSymbolContextLineEntry) {
358         if (m_flags.IsClear(eSymbolContextLineEntry)) {
359           if (m_sc.line_entry.IsValid())
360             resolved |= eSymbolContextLineEntry;
361           else
362             actual_resolve_scope |= eSymbolContextLineEntry;
363         }
364       }
365 
366       if (actual_resolve_scope) {
367         // We might be resolving less information than what is already
368         // in our current symbol context so resolve into a temporary
369         // symbol context "sc" so we don't clear out data we have
370         // already found in "m_sc"
371         SymbolContext sc;
372         // Set flags that indicate what we have tried to resolve
373         resolved |= m_sc.module_sp->ResolveSymbolContextForAddress(
374             lookup_addr, actual_resolve_scope, sc);
375         // Only replace what we didn't already have as we may have
376         // information for an inlined function scope that won't match
377         // what a standard lookup by address would match
378         if ((resolved & eSymbolContextCompUnit) && m_sc.comp_unit == nullptr)
379           m_sc.comp_unit = sc.comp_unit;
380         if ((resolved & eSymbolContextFunction) && m_sc.function == nullptr)
381           m_sc.function = sc.function;
382         if ((resolved & eSymbolContextBlock) && m_sc.block == nullptr)
383           m_sc.block = sc.block;
384         if ((resolved & eSymbolContextSymbol) && m_sc.symbol == nullptr)
385           m_sc.symbol = sc.symbol;
386         if ((resolved & eSymbolContextLineEntry) &&
387             !m_sc.line_entry.IsValid()) {
388           m_sc.line_entry = sc.line_entry;
389           m_sc.line_entry.ApplyFileMappings(m_sc.target_sp);
390         }
391       }
392     } else {
393       // If we don't have a module, then we can't have the compile unit,
394       // function, block, line entry or symbol, so we can safely call
395       // ResolveSymbolContextForAddress with our symbol context member m_sc.
396       if (m_sc.target_sp) {
397         resolved |= m_sc.target_sp->GetImages().ResolveSymbolContextForAddress(
398             lookup_addr, resolve_scope, m_sc);
399       }
400     }
401 
402     // Update our internal flags so we remember what we have tried to locate so
403     // we don't have to keep trying when more calls to this function are made.
404     // We might have dug up more information that was requested (for example
405     // if we were asked to only get the block, we will have gotten the
406     // compile unit, and function) so set any additional bits that we resolved
407     m_flags.Set(resolve_scope | resolved);
408   }
409 
410   // Return the symbol context with everything that was possible to resolve
411   // resolved.
412   return m_sc;
413 }
414 
415 VariableList *StackFrame::GetVariableList(bool get_file_globals) {
416   std::lock_guard<std::recursive_mutex> guard(m_mutex);
417   if (m_flags.IsClear(RESOLVED_VARIABLES)) {
418     m_flags.Set(RESOLVED_VARIABLES);
419 
420     Block *frame_block = GetFrameBlock();
421 
422     if (frame_block) {
423       const bool get_child_variables = true;
424       const bool can_create = true;
425       const bool stop_if_child_block_is_inlined_function = true;
426       m_variable_list_sp.reset(new VariableList());
427       frame_block->AppendBlockVariables(can_create, get_child_variables,
428                                         stop_if_child_block_is_inlined_function,
429                                         [this](Variable *v) { return true; },
430                                         m_variable_list_sp.get());
431     }
432   }
433 
434   if (m_flags.IsClear(RESOLVED_GLOBAL_VARIABLES) && get_file_globals) {
435     m_flags.Set(RESOLVED_GLOBAL_VARIABLES);
436 
437     if (m_flags.IsClear(eSymbolContextCompUnit))
438       GetSymbolContext(eSymbolContextCompUnit);
439 
440     if (m_sc.comp_unit) {
441       VariableListSP global_variable_list_sp(
442           m_sc.comp_unit->GetVariableList(true));
443       if (m_variable_list_sp)
444         m_variable_list_sp->AddVariables(global_variable_list_sp.get());
445       else
446         m_variable_list_sp = global_variable_list_sp;
447     }
448   }
449 
450   return m_variable_list_sp.get();
451 }
452 
453 VariableListSP
454 StackFrame::GetInScopeVariableList(bool get_file_globals,
455                                    bool must_have_valid_location) {
456   std::lock_guard<std::recursive_mutex> guard(m_mutex);
457   // We can't fetch variable information for a history stack frame.
458   if (m_is_history_frame)
459     return VariableListSP();
460 
461   VariableListSP var_list_sp(new VariableList);
462   GetSymbolContext(eSymbolContextCompUnit | eSymbolContextBlock);
463 
464   if (m_sc.block) {
465     const bool can_create = true;
466     const bool get_parent_variables = true;
467     const bool stop_if_block_is_inlined_function = true;
468     m_sc.block->AppendVariables(
469         can_create, get_parent_variables, stop_if_block_is_inlined_function,
470         [this, must_have_valid_location](Variable *v) {
471           return v->IsInScope(this) && (!must_have_valid_location ||
472                                         v->LocationIsValidForFrame(this));
473         },
474         var_list_sp.get());
475   }
476 
477   if (m_sc.comp_unit && get_file_globals) {
478     VariableListSP global_variable_list_sp(
479         m_sc.comp_unit->GetVariableList(true));
480     if (global_variable_list_sp)
481       var_list_sp->AddVariables(global_variable_list_sp.get());
482   }
483 
484   return var_list_sp;
485 }
486 
487 ValueObjectSP StackFrame::GetValueForVariableExpressionPath(
488     const char *var_expr_cstr, DynamicValueType use_dynamic, uint32_t options,
489     VariableSP &var_sp, Error &error) {
490   // We can't fetch variable information for a history stack frame.
491   if (m_is_history_frame)
492     return ValueObjectSP();
493 
494   if (var_expr_cstr && var_expr_cstr[0]) {
495     const bool check_ptr_vs_member =
496         (options & eExpressionPathOptionCheckPtrVsMember) != 0;
497     const bool no_fragile_ivar =
498         (options & eExpressionPathOptionsNoFragileObjcIvar) != 0;
499     const bool no_synth_child =
500         (options & eExpressionPathOptionsNoSyntheticChildren) != 0;
501     // const bool no_synth_array = (options &
502     // eExpressionPathOptionsNoSyntheticArrayRange) != 0;
503     error.Clear();
504     bool deref = false;
505     bool address_of = false;
506     ValueObjectSP valobj_sp;
507     const bool get_file_globals = true;
508     // When looking up a variable for an expression, we need only consider the
509     // variables that are in scope.
510     VariableListSP var_list_sp(GetInScopeVariableList(get_file_globals));
511     VariableList *variable_list = var_list_sp.get();
512 
513     if (variable_list) {
514       // If first character is a '*', then show pointer contents
515       const char *var_expr = var_expr_cstr;
516       if (var_expr[0] == '*') {
517         deref = true;
518         var_expr++; // Skip the '*'
519       } else if (var_expr[0] == '&') {
520         address_of = true;
521         var_expr++; // Skip the '&'
522       }
523 
524       std::string var_path(var_expr);
525       size_t separator_idx = var_path.find_first_of(".-[=+~|&^%#@!/?,<>{}");
526       StreamString var_expr_path_strm;
527 
528       ConstString name_const_string;
529       if (separator_idx == std::string::npos)
530         name_const_string.SetCString(var_path.c_str());
531       else
532         name_const_string.SetCStringWithLength(var_path.c_str(), separator_idx);
533 
534       var_sp = variable_list->FindVariable(name_const_string, false);
535 
536       bool synthetically_added_instance_object = false;
537 
538       if (var_sp) {
539         var_path.erase(0, name_const_string.GetLength());
540       }
541 
542       if (!var_sp && (options & eExpressionPathOptionsAllowDirectIVarAccess)) {
543         // Check for direct ivars access which helps us with implicit
544         // access to ivars with the "this->" or "self->"
545         GetSymbolContext(eSymbolContextFunction | eSymbolContextBlock);
546         lldb::LanguageType method_language = eLanguageTypeUnknown;
547         bool is_instance_method = false;
548         ConstString method_object_name;
549         if (m_sc.GetFunctionMethodInfo(method_language, is_instance_method,
550                                        method_object_name)) {
551           if (is_instance_method && method_object_name) {
552             var_sp = variable_list->FindVariable(method_object_name);
553             if (var_sp) {
554               separator_idx = 0;
555               var_path.insert(0, "->");
556               synthetically_added_instance_object = true;
557             }
558           }
559         }
560       }
561 
562       if (!var_sp && (options & eExpressionPathOptionsInspectAnonymousUnions)) {
563         // Check if any anonymous unions are there which contain a variable with
564         // the name we need
565         for (size_t i = 0; i < variable_list->GetSize(); i++) {
566           if (VariableSP variable_sp = variable_list->GetVariableAtIndex(i)) {
567             if (variable_sp->GetName().IsEmpty()) {
568               if (Type *var_type = variable_sp->GetType()) {
569                 if (var_type->GetForwardCompilerType().IsAnonymousType()) {
570                   valobj_sp =
571                       GetValueObjectForFrameVariable(variable_sp, use_dynamic);
572                   if (!valobj_sp)
573                     return valobj_sp;
574                   valobj_sp = valobj_sp->GetChildMemberWithName(
575                       name_const_string, true);
576                   if (valobj_sp)
577                     break;
578                 }
579               }
580             }
581           }
582         }
583       }
584 
585       if (var_sp && !valobj_sp) {
586         valobj_sp = GetValueObjectForFrameVariable(var_sp, use_dynamic);
587         if (!valobj_sp)
588           return valobj_sp;
589       }
590       if (valobj_sp) {
591         // We are dumping at least one child
592         while (separator_idx != std::string::npos) {
593           // Calculate the next separator index ahead of time
594           ValueObjectSP child_valobj_sp;
595           const char separator_type = var_path[0];
596           switch (separator_type) {
597           case '-':
598             if (var_path.size() >= 2 && var_path[1] != '>')
599               return ValueObjectSP();
600 
601             if (no_fragile_ivar) {
602               // Make sure we aren't trying to deref an objective
603               // C ivar if this is not allowed
604               const uint32_t pointer_type_flags =
605                   valobj_sp->GetCompilerType().GetTypeInfo(nullptr);
606               if ((pointer_type_flags & eTypeIsObjC) &&
607                   (pointer_type_flags & eTypeIsPointer)) {
608                 // This was an objective C object pointer and
609                 // it was requested we skip any fragile ivars
610                 // so return nothing here
611                 return ValueObjectSP();
612               }
613             }
614             var_path.erase(0, 1); // Remove the '-'
615             LLVM_FALLTHROUGH;
616           case '.': {
617             const bool expr_is_ptr = var_path[0] == '>';
618 
619             var_path.erase(0, 1); // Remove the '.' or '>'
620             separator_idx = var_path.find_first_of(".-[");
621             ConstString child_name;
622             if (separator_idx == std::string::npos)
623               child_name.SetCString(var_path.c_str());
624             else
625               child_name.SetCStringWithLength(var_path.c_str(), separator_idx);
626 
627             if (check_ptr_vs_member) {
628               // We either have a pointer type and need to verify
629               // valobj_sp is a pointer, or we have a member of a
630               // class/union/struct being accessed with the . syntax
631               // and need to verify we don't have a pointer.
632               const bool actual_is_ptr = valobj_sp->IsPointerType();
633 
634               if (actual_is_ptr != expr_is_ptr) {
635                 // Incorrect use of "." with a pointer, or "->" with
636                 // a class/union/struct instance or reference.
637                 valobj_sp->GetExpressionPath(var_expr_path_strm, false);
638                 if (actual_is_ptr)
639                   error.SetErrorStringWithFormat(
640                       "\"%s\" is a pointer and . was used to attempt to access "
641                       "\"%s\". Did you mean \"%s->%s\"?",
642                       var_expr_path_strm.GetData(), child_name.GetCString(),
643                       var_expr_path_strm.GetData(), var_path.c_str());
644                 else
645                   error.SetErrorStringWithFormat(
646                       "\"%s\" is not a pointer and -> was used to attempt to "
647                       "access \"%s\". Did you mean \"%s.%s\"?",
648                       var_expr_path_strm.GetData(), child_name.GetCString(),
649                       var_expr_path_strm.GetData(), var_path.c_str());
650                 return ValueObjectSP();
651               }
652             }
653             child_valobj_sp =
654                 valobj_sp->GetChildMemberWithName(child_name, true);
655             if (!child_valobj_sp) {
656               if (!no_synth_child) {
657                 child_valobj_sp = valobj_sp->GetSyntheticValue();
658                 if (child_valobj_sp)
659                   child_valobj_sp =
660                       child_valobj_sp->GetChildMemberWithName(child_name, true);
661               }
662 
663               if (no_synth_child || !child_valobj_sp) {
664                 // No child member with name "child_name"
665                 if (synthetically_added_instance_object) {
666                   // We added a "this->" or "self->" to the beginning of the
667                   // expression
668                   // and this is the first pointer ivar access, so just return
669                   // the normal
670                   // error
671                   error.SetErrorStringWithFormat(
672                       "no variable or instance variable named '%s' found in "
673                       "this frame",
674                       name_const_string.GetCString());
675                 } else {
676                   valobj_sp->GetExpressionPath(var_expr_path_strm, false);
677                   if (child_name) {
678                     error.SetErrorStringWithFormat(
679                         "\"%s\" is not a member of \"(%s) %s\"",
680                         child_name.GetCString(),
681                         valobj_sp->GetTypeName().AsCString("<invalid type>"),
682                         var_expr_path_strm.GetData());
683                   } else {
684                     error.SetErrorStringWithFormat(
685                         "incomplete expression path after \"%s\" in \"%s\"",
686                         var_expr_path_strm.GetData(), var_expr_cstr);
687                   }
688                 }
689                 return ValueObjectSP();
690               }
691             }
692             synthetically_added_instance_object = false;
693             // Remove the child name from the path
694             var_path.erase(0, child_name.GetLength());
695             if (use_dynamic != eNoDynamicValues) {
696               ValueObjectSP dynamic_value_sp(
697                   child_valobj_sp->GetDynamicValue(use_dynamic));
698               if (dynamic_value_sp)
699                 child_valobj_sp = dynamic_value_sp;
700             }
701           } break;
702 
703           case '[':
704             // Array member access, or treating pointer as an array
705             if (var_path.size() > 2) // Need at least two brackets and a number
706             {
707               char *end = nullptr;
708               long child_index = ::strtol(&var_path[1], &end, 0);
709               if (end && *end == ']' &&
710                   *(end - 1) != '[') // this code forces an error in the case of
711                                      // arr[]. as bitfield[] is not a good
712                                      // syntax we're good to go
713               {
714                 if (valobj_sp->GetCompilerType().IsPointerToScalarType() &&
715                     deref) {
716                   // what we have is *ptr[low]. the most similar C++ syntax is
717                   // to deref ptr
718                   // and extract bit low out of it. reading array item low
719                   // would be done by saying ptr[low], without a deref * sign
720                   Error error;
721                   ValueObjectSP temp(valobj_sp->Dereference(error));
722                   if (error.Fail()) {
723                     valobj_sp->GetExpressionPath(var_expr_path_strm, false);
724                     error.SetErrorStringWithFormat(
725                         "could not dereference \"(%s) %s\"",
726                         valobj_sp->GetTypeName().AsCString("<invalid type>"),
727                         var_expr_path_strm.GetData());
728                     return ValueObjectSP();
729                   }
730                   valobj_sp = temp;
731                   deref = false;
732                 } else if (valobj_sp->GetCompilerType().IsArrayOfScalarType() &&
733                            deref) {
734                   // what we have is *arr[low]. the most similar C++ syntax is
735                   // to get arr[0]
736                   // (an operation that is equivalent to deref-ing arr)
737                   // and extract bit low out of it. reading array item low
738                   // would be done by saying arr[low], without a deref * sign
739                   Error error;
740                   ValueObjectSP temp(valobj_sp->GetChildAtIndex(0, true));
741                   if (error.Fail()) {
742                     valobj_sp->GetExpressionPath(var_expr_path_strm, false);
743                     error.SetErrorStringWithFormat(
744                         "could not get item 0 for \"(%s) %s\"",
745                         valobj_sp->GetTypeName().AsCString("<invalid type>"),
746                         var_expr_path_strm.GetData());
747                     return ValueObjectSP();
748                   }
749                   valobj_sp = temp;
750                   deref = false;
751                 }
752 
753                 bool is_incomplete_array = false;
754                 if (valobj_sp->IsPointerType()) {
755                   bool is_objc_pointer = true;
756 
757                   if (valobj_sp->GetCompilerType().GetMinimumLanguage() !=
758                       eLanguageTypeObjC)
759                     is_objc_pointer = false;
760                   else if (!valobj_sp->GetCompilerType().IsPointerType())
761                     is_objc_pointer = false;
762 
763                   if (no_synth_child && is_objc_pointer) {
764                     error.SetErrorStringWithFormat(
765                         "\"(%s) %s\" is an Objective-C pointer, and cannot be "
766                         "subscripted",
767                         valobj_sp->GetTypeName().AsCString("<invalid type>"),
768                         var_expr_path_strm.GetData());
769 
770                     return ValueObjectSP();
771                   } else if (is_objc_pointer) {
772                     // dereferencing ObjC variables is not valid.. so let's try
773                     // and recur to synthetic children
774                     ValueObjectSP synthetic = valobj_sp->GetSyntheticValue();
775                     if (!synthetic                 /* no synthetic */
776                         || synthetic == valobj_sp) /* synthetic is the same as
777                                                       the original object */
778                     {
779                       valobj_sp->GetExpressionPath(var_expr_path_strm, false);
780                       error.SetErrorStringWithFormat(
781                           "\"(%s) %s\" is not an array type",
782                           valobj_sp->GetTypeName().AsCString("<invalid type>"),
783                           var_expr_path_strm.GetData());
784                     } else if (
785                         static_cast<uint32_t>(child_index) >=
786                         synthetic
787                             ->GetNumChildren() /* synthetic does not have that many values */) {
788                       valobj_sp->GetExpressionPath(var_expr_path_strm, false);
789                       error.SetErrorStringWithFormat(
790                           "array index %ld is not valid for \"(%s) %s\"",
791                           child_index,
792                           valobj_sp->GetTypeName().AsCString("<invalid type>"),
793                           var_expr_path_strm.GetData());
794                     } else {
795                       child_valobj_sp =
796                           synthetic->GetChildAtIndex(child_index, true);
797                       if (!child_valobj_sp) {
798                         valobj_sp->GetExpressionPath(var_expr_path_strm, false);
799                         error.SetErrorStringWithFormat(
800                             "array index %ld is not valid for \"(%s) %s\"",
801                             child_index, valobj_sp->GetTypeName().AsCString(
802                                              "<invalid type>"),
803                             var_expr_path_strm.GetData());
804                       }
805                     }
806                   } else {
807                     child_valobj_sp =
808                         valobj_sp->GetSyntheticArrayMember(child_index, true);
809                     if (!child_valobj_sp) {
810                       valobj_sp->GetExpressionPath(var_expr_path_strm, false);
811                       error.SetErrorStringWithFormat(
812                           "failed to use pointer as array for index %ld for "
813                           "\"(%s) %s\"",
814                           child_index,
815                           valobj_sp->GetTypeName().AsCString("<invalid type>"),
816                           var_expr_path_strm.GetData());
817                     }
818                   }
819                 } else if (valobj_sp->GetCompilerType().IsArrayType(
820                                nullptr, nullptr, &is_incomplete_array)) {
821                   // Pass false to dynamic_value here so we can tell the
822                   // difference between
823                   // no dynamic value and no member of this type...
824                   child_valobj_sp =
825                       valobj_sp->GetChildAtIndex(child_index, true);
826                   if (!child_valobj_sp &&
827                       (is_incomplete_array || !no_synth_child))
828                     child_valobj_sp =
829                         valobj_sp->GetSyntheticArrayMember(child_index, true);
830 
831                   if (!child_valobj_sp) {
832                     valobj_sp->GetExpressionPath(var_expr_path_strm, false);
833                     error.SetErrorStringWithFormat(
834                         "array index %ld is not valid for \"(%s) %s\"",
835                         child_index,
836                         valobj_sp->GetTypeName().AsCString("<invalid type>"),
837                         var_expr_path_strm.GetData());
838                   }
839                 } else if (valobj_sp->GetCompilerType().IsScalarType()) {
840                   // this is a bitfield asking to display just one bit
841                   child_valobj_sp = valobj_sp->GetSyntheticBitFieldChild(
842                       child_index, child_index, true);
843                   if (!child_valobj_sp) {
844                     valobj_sp->GetExpressionPath(var_expr_path_strm, false);
845                     error.SetErrorStringWithFormat(
846                         "bitfield range %ld-%ld is not valid for \"(%s) %s\"",
847                         child_index, child_index,
848                         valobj_sp->GetTypeName().AsCString("<invalid type>"),
849                         var_expr_path_strm.GetData());
850                   }
851                 } else {
852                   ValueObjectSP synthetic = valobj_sp->GetSyntheticValue();
853                   if (no_synth_child /* synthetic is forbidden */ ||
854                       !synthetic                 /* no synthetic */
855                       || synthetic == valobj_sp) /* synthetic is the same as the
856                                                     original object */
857                   {
858                     valobj_sp->GetExpressionPath(var_expr_path_strm, false);
859                     error.SetErrorStringWithFormat(
860                         "\"(%s) %s\" is not an array type",
861                         valobj_sp->GetTypeName().AsCString("<invalid type>"),
862                         var_expr_path_strm.GetData());
863                   } else if (
864                       static_cast<uint32_t>(child_index) >=
865                       synthetic
866                           ->GetNumChildren() /* synthetic does not have that many values */) {
867                     valobj_sp->GetExpressionPath(var_expr_path_strm, false);
868                     error.SetErrorStringWithFormat(
869                         "array index %ld is not valid for \"(%s) %s\"",
870                         child_index,
871                         valobj_sp->GetTypeName().AsCString("<invalid type>"),
872                         var_expr_path_strm.GetData());
873                   } else {
874                     child_valobj_sp =
875                         synthetic->GetChildAtIndex(child_index, true);
876                     if (!child_valobj_sp) {
877                       valobj_sp->GetExpressionPath(var_expr_path_strm, false);
878                       error.SetErrorStringWithFormat(
879                           "array index %ld is not valid for \"(%s) %s\"",
880                           child_index,
881                           valobj_sp->GetTypeName().AsCString("<invalid type>"),
882                           var_expr_path_strm.GetData());
883                     }
884                   }
885                 }
886 
887                 if (!child_valobj_sp) {
888                   // Invalid array index...
889                   return ValueObjectSP();
890                 }
891 
892                 // Erase the array member specification '[%i]' where
893                 // %i is the array index
894                 var_path.erase(0, (end - var_path.c_str()) + 1);
895                 separator_idx = var_path.find_first_of(".-[");
896                 if (use_dynamic != eNoDynamicValues) {
897                   ValueObjectSP dynamic_value_sp(
898                       child_valobj_sp->GetDynamicValue(use_dynamic));
899                   if (dynamic_value_sp)
900                     child_valobj_sp = dynamic_value_sp;
901                 }
902                 // Break out early from the switch since we were
903                 // able to find the child member
904                 break;
905               } else if (end && *end == '-') {
906                 // this is most probably a BitField, let's take a look
907                 char *real_end = nullptr;
908                 long final_index = ::strtol(end + 1, &real_end, 0);
909                 bool expand_bitfield = true;
910                 if (real_end && *real_end == ']') {
911                   // if the format given is [high-low], swap range
912                   if (child_index > final_index) {
913                     long temp = child_index;
914                     child_index = final_index;
915                     final_index = temp;
916                   }
917 
918                   if (valobj_sp->GetCompilerType().IsPointerToScalarType() &&
919                       deref) {
920                     // what we have is *ptr[low-high]. the most similar C++
921                     // syntax is to deref ptr
922                     // and extract bits low thru high out of it. reading array
923                     // items low thru high
924                     // would be done by saying ptr[low-high], without a deref *
925                     // sign
926                     Error error;
927                     ValueObjectSP temp(valobj_sp->Dereference(error));
928                     if (error.Fail()) {
929                       valobj_sp->GetExpressionPath(var_expr_path_strm, false);
930                       error.SetErrorStringWithFormat(
931                           "could not dereference \"(%s) %s\"",
932                           valobj_sp->GetTypeName().AsCString("<invalid type>"),
933                           var_expr_path_strm.GetData());
934                       return ValueObjectSP();
935                     }
936                     valobj_sp = temp;
937                     deref = false;
938                   } else if (valobj_sp->GetCompilerType()
939                                  .IsArrayOfScalarType() &&
940                              deref) {
941                     // what we have is *arr[low-high]. the most similar C++
942                     // syntax is to get arr[0]
943                     // (an operation that is equivalent to deref-ing arr)
944                     // and extract bits low thru high out of it. reading array
945                     // items low thru high
946                     // would be done by saying arr[low-high], without a deref *
947                     // sign
948                     Error error;
949                     ValueObjectSP temp(valobj_sp->GetChildAtIndex(0, true));
950                     if (error.Fail()) {
951                       valobj_sp->GetExpressionPath(var_expr_path_strm, false);
952                       error.SetErrorStringWithFormat(
953                           "could not get item 0 for \"(%s) %s\"",
954                           valobj_sp->GetTypeName().AsCString("<invalid type>"),
955                           var_expr_path_strm.GetData());
956                       return ValueObjectSP();
957                     }
958                     valobj_sp = temp;
959                     deref = false;
960                   }
961                   /*else if (valobj_sp->IsArrayType() ||
962                   valobj_sp->IsPointerType())
963                   {
964                       child_valobj_sp =
965                   valobj_sp->GetSyntheticArrayRangeChild(child_index,
966                   final_index, true);
967                       expand_bitfield = false;
968                       if (!child_valobj_sp)
969                       {
970                           valobj_sp->GetExpressionPath (var_expr_path_strm,
971                   false);
972                           error.SetErrorStringWithFormat ("array range %i-%i is
973                   not valid for \"(%s) %s\"",
974                                                           child_index,
975                   final_index,
976                                                           valobj_sp->GetTypeName().AsCString("<invalid
977                   type>"),
978                                                           var_expr_path_strm.c_str());
979                       }
980                   }*/
981 
982                   if (expand_bitfield) {
983                     child_valobj_sp = valobj_sp->GetSyntheticBitFieldChild(
984                         child_index, final_index, true);
985                     if (!child_valobj_sp) {
986                       valobj_sp->GetExpressionPath(var_expr_path_strm, false);
987                       error.SetErrorStringWithFormat(
988                           "bitfield range %ld-%ld is not valid for \"(%s) %s\"",
989                           child_index, final_index,
990                           valobj_sp->GetTypeName().AsCString("<invalid type>"),
991                           var_expr_path_strm.GetData());
992                     }
993                   }
994                 }
995 
996                 if (!child_valobj_sp) {
997                   // Invalid bitfield range...
998                   return ValueObjectSP();
999                 }
1000 
1001                 // Erase the bitfield member specification '[%i-%i]' where
1002                 // %i is the index
1003                 var_path.erase(0, (real_end - var_path.c_str()) + 1);
1004                 separator_idx = var_path.find_first_of(".-[");
1005                 if (use_dynamic != eNoDynamicValues) {
1006                   ValueObjectSP dynamic_value_sp(
1007                       child_valobj_sp->GetDynamicValue(use_dynamic));
1008                   if (dynamic_value_sp)
1009                     child_valobj_sp = dynamic_value_sp;
1010                 }
1011                 // Break out early from the switch since we were
1012                 // able to find the child member
1013                 break;
1014               }
1015             } else {
1016               error.SetErrorStringWithFormat(
1017                   "invalid square bracket encountered after \"%s\" in \"%s\"",
1018                   var_expr_path_strm.GetData(), var_path.c_str());
1019             }
1020             return ValueObjectSP();
1021 
1022           default:
1023             // Failure...
1024             {
1025               valobj_sp->GetExpressionPath(var_expr_path_strm, false);
1026               error.SetErrorStringWithFormat(
1027                   "unexpected char '%c' encountered after \"%s\" in \"%s\"",
1028                   separator_type, var_expr_path_strm.GetData(),
1029                   var_path.c_str());
1030 
1031               return ValueObjectSP();
1032             }
1033           }
1034 
1035           if (child_valobj_sp)
1036             valobj_sp = child_valobj_sp;
1037 
1038           if (var_path.empty())
1039             break;
1040         }
1041         if (valobj_sp) {
1042           if (deref) {
1043             ValueObjectSP deref_valobj_sp(valobj_sp->Dereference(error));
1044             valobj_sp = deref_valobj_sp;
1045           } else if (address_of) {
1046             ValueObjectSP address_of_valobj_sp(valobj_sp->AddressOf(error));
1047             valobj_sp = address_of_valobj_sp;
1048           }
1049         }
1050         return valobj_sp;
1051       } else {
1052         error.SetErrorStringWithFormat(
1053             "no variable named '%s' found in this frame",
1054             name_const_string.GetCString());
1055       }
1056     }
1057   } else {
1058     error.SetErrorStringWithFormat("invalid variable path '%s'", var_expr_cstr);
1059   }
1060   return ValueObjectSP();
1061 }
1062 
1063 bool StackFrame::GetFrameBaseValue(Scalar &frame_base, Error *error_ptr) {
1064   std::lock_guard<std::recursive_mutex> guard(m_mutex);
1065   if (!m_cfa_is_valid) {
1066     m_frame_base_error.SetErrorString(
1067         "No frame base available for this historical stack frame.");
1068     return false;
1069   }
1070 
1071   if (m_flags.IsClear(GOT_FRAME_BASE)) {
1072     if (m_sc.function) {
1073       m_frame_base.Clear();
1074       m_frame_base_error.Clear();
1075 
1076       m_flags.Set(GOT_FRAME_BASE);
1077       ExecutionContext exe_ctx(shared_from_this());
1078       Value expr_value;
1079       addr_t loclist_base_addr = LLDB_INVALID_ADDRESS;
1080       if (m_sc.function->GetFrameBaseExpression().IsLocationList())
1081         loclist_base_addr =
1082             m_sc.function->GetAddressRange().GetBaseAddress().GetLoadAddress(
1083                 exe_ctx.GetTargetPtr());
1084 
1085       if (m_sc.function->GetFrameBaseExpression().Evaluate(
1086               &exe_ctx, nullptr, nullptr, nullptr, loclist_base_addr, nullptr,
1087               nullptr, expr_value, &m_frame_base_error) == false) {
1088         // We should really have an error if evaluate returns, but in case
1089         // we don't, lets set the error to something at least.
1090         if (m_frame_base_error.Success())
1091           m_frame_base_error.SetErrorString(
1092               "Evaluation of the frame base expression failed.");
1093       } else {
1094         m_frame_base = expr_value.ResolveValue(&exe_ctx);
1095       }
1096     } else {
1097       m_frame_base_error.SetErrorString("No function in symbol context.");
1098     }
1099   }
1100 
1101   if (m_frame_base_error.Success())
1102     frame_base = m_frame_base;
1103 
1104   if (error_ptr)
1105     *error_ptr = m_frame_base_error;
1106   return m_frame_base_error.Success();
1107 }
1108 
1109 DWARFExpression *StackFrame::GetFrameBaseExpression(Error *error_ptr) {
1110   if (!m_sc.function) {
1111     if (error_ptr) {
1112       error_ptr->SetErrorString("No function in symbol context.");
1113     }
1114     return nullptr;
1115   }
1116 
1117   return &m_sc.function->GetFrameBaseExpression();
1118 }
1119 
1120 RegisterContextSP StackFrame::GetRegisterContext() {
1121   std::lock_guard<std::recursive_mutex> guard(m_mutex);
1122   if (!m_reg_context_sp) {
1123     ThreadSP thread_sp(GetThread());
1124     if (thread_sp)
1125       m_reg_context_sp = thread_sp->CreateRegisterContextForFrame(this);
1126   }
1127   return m_reg_context_sp;
1128 }
1129 
1130 bool StackFrame::HasDebugInformation() {
1131   GetSymbolContext(eSymbolContextLineEntry);
1132   return m_sc.line_entry.IsValid();
1133 }
1134 
1135 ValueObjectSP
1136 StackFrame::GetValueObjectForFrameVariable(const VariableSP &variable_sp,
1137                                            DynamicValueType use_dynamic) {
1138   std::lock_guard<std::recursive_mutex> guard(m_mutex);
1139   ValueObjectSP valobj_sp;
1140   if (m_is_history_frame) {
1141     return valobj_sp;
1142   }
1143   VariableList *var_list = GetVariableList(true);
1144   if (var_list) {
1145     // Make sure the variable is a frame variable
1146     const uint32_t var_idx = var_list->FindIndexForVariable(variable_sp.get());
1147     const uint32_t num_variables = var_list->GetSize();
1148     if (var_idx < num_variables) {
1149       valobj_sp = m_variable_list_value_objects.GetValueObjectAtIndex(var_idx);
1150       if (!valobj_sp) {
1151         if (m_variable_list_value_objects.GetSize() < num_variables)
1152           m_variable_list_value_objects.Resize(num_variables);
1153         valobj_sp = ValueObjectVariable::Create(this, variable_sp);
1154         m_variable_list_value_objects.SetValueObjectAtIndex(var_idx, valobj_sp);
1155       }
1156     }
1157   }
1158   if (use_dynamic != eNoDynamicValues && valobj_sp) {
1159     ValueObjectSP dynamic_sp = valobj_sp->GetDynamicValue(use_dynamic);
1160     if (dynamic_sp)
1161       return dynamic_sp;
1162   }
1163   return valobj_sp;
1164 }
1165 
1166 ValueObjectSP StackFrame::TrackGlobalVariable(const VariableSP &variable_sp,
1167                                               DynamicValueType use_dynamic) {
1168   std::lock_guard<std::recursive_mutex> guard(m_mutex);
1169   if (m_is_history_frame)
1170     return ValueObjectSP();
1171 
1172   // Check to make sure we aren't already tracking this variable?
1173   ValueObjectSP valobj_sp(
1174       GetValueObjectForFrameVariable(variable_sp, use_dynamic));
1175   if (!valobj_sp) {
1176     // We aren't already tracking this global
1177     VariableList *var_list = GetVariableList(true);
1178     // If this frame has no variables, create a new list
1179     if (var_list == nullptr)
1180       m_variable_list_sp.reset(new VariableList());
1181 
1182     // Add the global/static variable to this frame
1183     m_variable_list_sp->AddVariable(variable_sp);
1184 
1185     // Now make a value object for it so we can track its changes
1186     valobj_sp = GetValueObjectForFrameVariable(variable_sp, use_dynamic);
1187   }
1188   return valobj_sp;
1189 }
1190 
1191 bool StackFrame::IsInlined() {
1192   if (m_sc.block == nullptr)
1193     GetSymbolContext(eSymbolContextBlock);
1194   if (m_sc.block)
1195     return m_sc.block->GetContainingInlinedBlock() != nullptr;
1196   return false;
1197 }
1198 
1199 lldb::LanguageType StackFrame::GetLanguage() {
1200   CompileUnit *cu = GetSymbolContext(eSymbolContextCompUnit).comp_unit;
1201   if (cu)
1202     return cu->GetLanguage();
1203   return lldb::eLanguageTypeUnknown;
1204 }
1205 
1206 lldb::LanguageType StackFrame::GuessLanguage() {
1207   LanguageType lang_type = GetLanguage();
1208 
1209   if (lang_type == eLanguageTypeUnknown) {
1210     Function *f = GetSymbolContext(eSymbolContextFunction).function;
1211     if (f) {
1212       lang_type = f->GetMangled().GuessLanguage();
1213     }
1214   }
1215 
1216   return lang_type;
1217 }
1218 
1219 namespace {
1220 std::pair<const Instruction::Operand *, int64_t>
1221 GetBaseExplainingValue(const Instruction::Operand &operand,
1222                        RegisterContext &register_context, lldb::addr_t value) {
1223   switch (operand.m_type) {
1224   case Instruction::Operand::Type::Dereference:
1225   case Instruction::Operand::Type::Immediate:
1226   case Instruction::Operand::Type::Invalid:
1227   case Instruction::Operand::Type::Product:
1228     // These are not currently interesting
1229     return std::make_pair(nullptr, 0);
1230   case Instruction::Operand::Type::Sum: {
1231     const Instruction::Operand *immediate_child = nullptr;
1232     const Instruction::Operand *variable_child = nullptr;
1233     if (operand.m_children[0].m_type == Instruction::Operand::Type::Immediate) {
1234       immediate_child = &operand.m_children[0];
1235       variable_child = &operand.m_children[1];
1236     } else if (operand.m_children[1].m_type ==
1237                Instruction::Operand::Type::Immediate) {
1238       immediate_child = &operand.m_children[1];
1239       variable_child = &operand.m_children[0];
1240     }
1241     if (!immediate_child) {
1242       return std::make_pair(nullptr, 0);
1243     }
1244     lldb::addr_t adjusted_value = value;
1245     if (immediate_child->m_negative) {
1246       adjusted_value += immediate_child->m_immediate;
1247     } else {
1248       adjusted_value -= immediate_child->m_immediate;
1249     }
1250     std::pair<const Instruction::Operand *, int64_t> base_and_offset =
1251         GetBaseExplainingValue(*variable_child, register_context,
1252                                adjusted_value);
1253     if (!base_and_offset.first) {
1254       return std::make_pair(nullptr, 0);
1255     }
1256     if (immediate_child->m_negative) {
1257       base_and_offset.second -= immediate_child->m_immediate;
1258     } else {
1259       base_and_offset.second += immediate_child->m_immediate;
1260     }
1261     return base_and_offset;
1262   }
1263   case Instruction::Operand::Type::Register: {
1264     const RegisterInfo *info =
1265         register_context.GetRegisterInfoByName(operand.m_register.AsCString());
1266     if (!info) {
1267       return std::make_pair(nullptr, 0);
1268     }
1269     RegisterValue reg_value;
1270     if (!register_context.ReadRegister(info, reg_value)) {
1271       return std::make_pair(nullptr, 0);
1272     }
1273     if (reg_value.GetAsUInt64() == value) {
1274       return std::make_pair(&operand, 0);
1275     } else {
1276       return std::make_pair(nullptr, 0);
1277     }
1278   }
1279   }
1280   return std::make_pair(nullptr, 0);
1281 }
1282 
1283 std::pair<const Instruction::Operand *, int64_t>
1284 GetBaseExplainingDereference(const Instruction::Operand &operand,
1285                              RegisterContext &register_context,
1286                              lldb::addr_t addr) {
1287   if (operand.m_type == Instruction::Operand::Type::Dereference) {
1288     return GetBaseExplainingValue(operand.m_children[0], register_context,
1289                                   addr);
1290   }
1291   return std::make_pair(nullptr, 0);
1292 }
1293 }
1294 
1295 lldb::ValueObjectSP StackFrame::GuessValueForAddress(lldb::addr_t addr) {
1296   TargetSP target_sp = CalculateTarget();
1297 
1298   const ArchSpec &target_arch = target_sp->GetArchitecture();
1299 
1300   AddressRange pc_range;
1301   pc_range.GetBaseAddress() = GetFrameCodeAddress();
1302   pc_range.SetByteSize(target_arch.GetMaximumOpcodeByteSize());
1303 
1304   ExecutionContext exe_ctx(shared_from_this());
1305 
1306   const char *plugin_name = nullptr;
1307   const char *flavor = nullptr;
1308   const bool prefer_file_cache = false;
1309 
1310   DisassemblerSP disassembler_sp = Disassembler::DisassembleRange(
1311       target_arch, plugin_name, flavor, exe_ctx, pc_range, prefer_file_cache);
1312 
1313   if (!disassembler_sp->GetInstructionList().GetSize()) {
1314     return ValueObjectSP();
1315   }
1316 
1317   InstructionSP instruction_sp =
1318       disassembler_sp->GetInstructionList().GetInstructionAtIndex(0);
1319 
1320   llvm::SmallVector<Instruction::Operand, 3> operands;
1321 
1322   if (!instruction_sp->ParseOperands(operands)) {
1323     return ValueObjectSP();
1324   }
1325 
1326   RegisterContextSP register_context_sp = GetRegisterContext();
1327 
1328   if (!register_context_sp) {
1329     return ValueObjectSP();
1330   }
1331 
1332   for (const Instruction::Operand &operand : operands) {
1333     std::pair<const Instruction::Operand *, int64_t> base_and_offset =
1334         GetBaseExplainingDereference(operand, *register_context_sp, addr);
1335 
1336     if (!base_and_offset.first) {
1337       continue;
1338     }
1339 
1340     switch (base_and_offset.first->m_type) {
1341     case Instruction::Operand::Type::Immediate: {
1342       lldb_private::Address addr;
1343       if (target_sp->ResolveLoadAddress(base_and_offset.first->m_immediate +
1344                                             base_and_offset.second,
1345                                         addr)) {
1346         TypeSystem *c_type_system =
1347             target_sp->GetScratchTypeSystemForLanguage(nullptr, eLanguageTypeC);
1348         if (!c_type_system) {
1349           return ValueObjectSP();
1350         } else {
1351           CompilerType void_ptr_type =
1352               c_type_system
1353                   ->GetBasicTypeFromAST(lldb::BasicType::eBasicTypeChar)
1354                   .GetPointerType();
1355           return ValueObjectMemory::Create(this, "", addr, void_ptr_type);
1356         }
1357       } else {
1358         return ValueObjectSP();
1359       }
1360       break;
1361     }
1362     case Instruction::Operand::Type::Register: {
1363       return GuessValueForRegisterAndOffset(base_and_offset.first->m_register,
1364                                             base_and_offset.second);
1365     }
1366     default:
1367       return ValueObjectSP();
1368     }
1369   }
1370 
1371   return ValueObjectSP();
1372 }
1373 
1374 namespace {
1375 ValueObjectSP GetValueForOffset(StackFrame &frame, ValueObjectSP &parent,
1376                                 int64_t offset) {
1377   if (offset < 0 || uint64_t(offset) >= parent->GetByteSize()) {
1378     return ValueObjectSP();
1379   }
1380 
1381   if (parent->IsPointerOrReferenceType()) {
1382     return parent;
1383   }
1384 
1385   for (int ci = 0, ce = parent->GetNumChildren(); ci != ce; ++ci) {
1386     const bool can_create = true;
1387     ValueObjectSP child_sp = parent->GetChildAtIndex(ci, can_create);
1388 
1389     if (!child_sp) {
1390       return ValueObjectSP();
1391     }
1392 
1393     int64_t child_offset = child_sp->GetByteOffset();
1394     int64_t child_size = child_sp->GetByteSize();
1395 
1396     if (offset >= child_offset && offset < (child_offset + child_size)) {
1397       return GetValueForOffset(frame, child_sp, offset - child_offset);
1398     }
1399   }
1400 
1401   if (offset == 0) {
1402     return parent;
1403   } else {
1404     return ValueObjectSP();
1405   }
1406 }
1407 
1408 ValueObjectSP GetValueForDereferincingOffset(StackFrame &frame,
1409                                              ValueObjectSP &base,
1410                                              int64_t offset) {
1411   // base is a pointer to something
1412   // offset is the thing to add to the pointer
1413   // We return the most sensible ValueObject for the result of *(base+offset)
1414 
1415   if (!base->IsPointerOrReferenceType()) {
1416     return ValueObjectSP();
1417   }
1418 
1419   Error error;
1420   ValueObjectSP pointee = base->Dereference(error);
1421 
1422   if (!pointee) {
1423     return ValueObjectSP();
1424   }
1425 
1426   if (offset >= 0 && uint64_t(offset) >= pointee->GetByteSize()) {
1427     int64_t index = offset / pointee->GetByteSize();
1428     offset = offset % pointee->GetByteSize();
1429     const bool can_create = true;
1430     pointee = base->GetSyntheticArrayMember(index, can_create);
1431   }
1432 
1433   if (!pointee || error.Fail()) {
1434     return ValueObjectSP();
1435   }
1436 
1437   return GetValueForOffset(frame, pointee, offset);
1438 }
1439 
1440 //------------------------------------------------------------------
1441 /// Attempt to reconstruct the ValueObject for the address contained in a
1442 /// given register plus an offset.
1443 ///
1444 /// @params [in] frame
1445 ///   The current stack frame.
1446 ///
1447 /// @params [in] reg
1448 ///   The register.
1449 ///
1450 /// @params [in] offset
1451 ///   The offset from the register.
1452 ///
1453 /// @param [in] disassembler
1454 ///   A disassembler containing instructions valid up to the current PC.
1455 ///
1456 /// @param [in] variables
1457 ///   The variable list from the current frame,
1458 ///
1459 /// @param [in] pc
1460 ///   The program counter for the instruction considered the 'user'.
1461 ///
1462 /// @return
1463 ///   A string describing the base for the ExpressionPath.  This could be a
1464 ///     variable, a register value, an argument, or a function return value.
1465 ///   The ValueObject if found.  If valid, it has a valid ExpressionPath.
1466 //------------------------------------------------------------------
1467 lldb::ValueObjectSP DoGuessValueAt(StackFrame &frame, ConstString reg,
1468                                    int64_t offset, Disassembler &disassembler,
1469                                    VariableList &variables, const Address &pc) {
1470   // Example of operation for Intel:
1471   //
1472   // +14: movq   -0x8(%rbp), %rdi
1473   // +18: movq   0x8(%rdi), %rdi
1474   // +22: addl   0x4(%rdi), %eax
1475   //
1476   // f, a pointer to a struct, is known to be at -0x8(%rbp).
1477   //
1478   // DoGuessValueAt(frame, rdi, 4, dis, vars, 0x22) finds the instruction at +18
1479   // that assigns to rdi, and calls itself recursively for that dereference
1480   //   DoGuessValueAt(frame, rdi, 8, dis, vars, 0x18) finds the instruction at
1481   //   +14 that assigns to rdi, and calls itself recursively for that
1482   //   derefernece
1483   //     DoGuessValueAt(frame, rbp, -8, dis, vars, 0x14) finds "f" in the
1484   //     variable list.
1485   //     Returns a ValueObject for f.  (That's what was stored at rbp-8 at +14)
1486   //   Returns a ValueObject for *(f+8) or f->b (That's what was stored at rdi+8
1487   //   at +18)
1488   // Returns a ValueObject for *(f->b+4) or f->b->a (That's what was stored at
1489   // rdi+4 at +22)
1490 
1491   // First, check the variable list to see if anything is at the specified
1492   // location.
1493 
1494   using namespace OperandMatchers;
1495 
1496   const RegisterInfo *reg_info =
1497       frame.GetRegisterContext()->GetRegisterInfoByName(reg.AsCString());
1498   if (!reg_info) {
1499     return ValueObjectSP();
1500   }
1501 
1502   Instruction::Operand op =
1503       offset ? Instruction::Operand::BuildDereference(
1504                    Instruction::Operand::BuildSum(
1505                        Instruction::Operand::BuildRegister(reg),
1506                        Instruction::Operand::BuildImmediate(offset)))
1507              : Instruction::Operand::BuildDereference(
1508                    Instruction::Operand::BuildRegister(reg));
1509 
1510   for (size_t vi = 0, ve = variables.GetSize(); vi != ve; ++vi) {
1511     VariableSP var_sp = variables.GetVariableAtIndex(vi);
1512     if (var_sp->LocationExpression().MatchesOperand(frame, op)) {
1513       return frame.GetValueObjectForFrameVariable(var_sp, eNoDynamicValues);
1514     }
1515   }
1516 
1517   const uint32_t current_inst =
1518       disassembler.GetInstructionList().GetIndexOfInstructionAtAddress(pc);
1519   if (current_inst == UINT32_MAX) {
1520     return ValueObjectSP();
1521   }
1522 
1523   for (uint32_t ii = current_inst - 1; ii != (uint32_t)-1; --ii) {
1524     // This is not an exact algorithm, and it sacrifices accuracy for
1525     // generality.  Recognizing "mov" and "ld" instructions –– and which are
1526     // their source and destination operands -- is something the disassembler
1527     // should do for us.
1528     InstructionSP instruction_sp =
1529         disassembler.GetInstructionList().GetInstructionAtIndex(ii);
1530 
1531     if (instruction_sp->IsCall()) {
1532       ABISP abi_sp = frame.CalculateProcess()->GetABI();
1533       if (!abi_sp) {
1534         continue;
1535       }
1536 
1537       const char *return_register_name;
1538       if (!abi_sp->GetPointerReturnRegister(return_register_name)) {
1539         continue;
1540       }
1541 
1542       const RegisterInfo *return_register_info =
1543           frame.GetRegisterContext()->GetRegisterInfoByName(
1544               return_register_name);
1545       if (!return_register_info) {
1546         continue;
1547       }
1548 
1549       int64_t offset = 0;
1550 
1551       if (!MatchUnaryOp(MatchOpType(Instruction::Operand::Type::Dereference),
1552                         MatchRegOp(*return_register_info))(op) &&
1553           !MatchUnaryOp(
1554               MatchOpType(Instruction::Operand::Type::Dereference),
1555               MatchBinaryOp(MatchOpType(Instruction::Operand::Type::Sum),
1556                             MatchRegOp(*return_register_info),
1557                             FetchImmOp(offset)))(op)) {
1558         continue;
1559       }
1560 
1561       llvm::SmallVector<Instruction::Operand, 1> operands;
1562       if (!instruction_sp->ParseOperands(operands) || operands.size() != 1) {
1563         continue;
1564       }
1565 
1566       switch (operands[0].m_type) {
1567       default:
1568         break;
1569       case Instruction::Operand::Type::Immediate: {
1570         SymbolContext sc;
1571         Address load_address;
1572         if (!frame.CalculateTarget()->ResolveLoadAddress(
1573                 operands[0].m_immediate, load_address)) {
1574           break;
1575         }
1576         frame.CalculateTarget()->GetImages().ResolveSymbolContextForAddress(
1577             load_address, eSymbolContextFunction, sc);
1578         if (!sc.function) {
1579           break;
1580         }
1581         CompilerType function_type = sc.function->GetCompilerType();
1582         if (!function_type.IsFunctionType()) {
1583           break;
1584         }
1585         CompilerType return_type = function_type.GetFunctionReturnType();
1586         RegisterValue return_value;
1587         if (!frame.GetRegisterContext()->ReadRegister(return_register_info,
1588                                                       return_value)) {
1589           break;
1590         }
1591         std::string name_str(
1592             sc.function->GetName().AsCString("<unknown function>"));
1593         name_str.append("()");
1594         Address return_value_address(return_value.GetAsUInt64());
1595         ValueObjectSP return_value_sp = ValueObjectMemory::Create(
1596             &frame, name_str, return_value_address, return_type);
1597         return GetValueForDereferincingOffset(frame, return_value_sp, offset);
1598       }
1599       }
1600 
1601       continue;
1602     }
1603 
1604     llvm::SmallVector<Instruction::Operand, 2> operands;
1605     if (!instruction_sp->ParseOperands(operands) || operands.size() != 2) {
1606       continue;
1607     }
1608 
1609     Instruction::Operand *origin_operand = nullptr;
1610     auto clobbered_reg_matcher = [reg_info](const Instruction::Operand &op) {
1611       return MatchRegOp(*reg_info)(op) && op.m_clobbered;
1612     };
1613 
1614     if (clobbered_reg_matcher(operands[0])) {
1615       origin_operand = &operands[1];
1616     }
1617     else if (clobbered_reg_matcher(operands[1])) {
1618       origin_operand = &operands[0];
1619     }
1620     else {
1621       continue;
1622     }
1623 
1624     // We have an origin operand.  Can we track its value down?
1625     ValueObjectSP source_path;
1626     ConstString origin_register;
1627     int64_t origin_offset = 0;
1628 
1629     if (FetchRegOp(origin_register)(*origin_operand)) {
1630       source_path = DoGuessValueAt(frame, origin_register, 0, disassembler,
1631                                    variables, instruction_sp->GetAddress());
1632     } else if (MatchUnaryOp(
1633                    MatchOpType(Instruction::Operand::Type::Dereference),
1634                    FetchRegOp(origin_register))(*origin_operand) ||
1635                MatchUnaryOp(
1636                    MatchOpType(Instruction::Operand::Type::Dereference),
1637                    MatchBinaryOp(MatchOpType(Instruction::Operand::Type::Sum),
1638                                  FetchRegOp(origin_register),
1639                                  FetchImmOp(origin_offset)))(*origin_operand)) {
1640       source_path =
1641           DoGuessValueAt(frame, origin_register, origin_offset, disassembler,
1642                          variables, instruction_sp->GetAddress());
1643       if (!source_path) {
1644         continue;
1645       }
1646       source_path =
1647           GetValueForDereferincingOffset(frame, source_path, offset);
1648     }
1649 
1650     if (source_path) {
1651       return source_path;
1652     }
1653   }
1654 
1655   return ValueObjectSP();
1656 }
1657 }
1658 
1659 lldb::ValueObjectSP StackFrame::GuessValueForRegisterAndOffset(ConstString reg,
1660                                                                int64_t offset) {
1661   TargetSP target_sp = CalculateTarget();
1662 
1663   const ArchSpec &target_arch = target_sp->GetArchitecture();
1664 
1665   Block *frame_block = GetFrameBlock();
1666 
1667   if (!frame_block) {
1668     return ValueObjectSP();
1669   }
1670 
1671   Function *function = frame_block->CalculateSymbolContextFunction();
1672   if (!function) {
1673     return ValueObjectSP();
1674   }
1675 
1676   AddressRange pc_range = function->GetAddressRange();
1677 
1678   if (GetFrameCodeAddress().GetFileAddress() <
1679           pc_range.GetBaseAddress().GetFileAddress() ||
1680       GetFrameCodeAddress().GetFileAddress() -
1681               pc_range.GetBaseAddress().GetFileAddress() >=
1682           pc_range.GetByteSize()) {
1683     return ValueObjectSP();
1684   }
1685 
1686   ExecutionContext exe_ctx(shared_from_this());
1687 
1688   const char *plugin_name = nullptr;
1689   const char *flavor = nullptr;
1690   const bool prefer_file_cache = false;
1691   DisassemblerSP disassembler_sp = Disassembler::DisassembleRange(
1692       target_arch, plugin_name, flavor, exe_ctx, pc_range, prefer_file_cache);
1693 
1694   if (!disassembler_sp || !disassembler_sp->GetInstructionList().GetSize()) {
1695     return ValueObjectSP();
1696   }
1697 
1698   const bool get_file_globals = false;
1699   VariableList *variables = GetVariableList(get_file_globals);
1700 
1701   if (!variables) {
1702     return ValueObjectSP();
1703   }
1704 
1705   return DoGuessValueAt(*this, reg, offset, *disassembler_sp, *variables,
1706                         GetFrameCodeAddress());
1707 }
1708 
1709 TargetSP StackFrame::CalculateTarget() {
1710   TargetSP target_sp;
1711   ThreadSP thread_sp(GetThread());
1712   if (thread_sp) {
1713     ProcessSP process_sp(thread_sp->CalculateProcess());
1714     if (process_sp)
1715       target_sp = process_sp->CalculateTarget();
1716   }
1717   return target_sp;
1718 }
1719 
1720 ProcessSP StackFrame::CalculateProcess() {
1721   ProcessSP process_sp;
1722   ThreadSP thread_sp(GetThread());
1723   if (thread_sp)
1724     process_sp = thread_sp->CalculateProcess();
1725   return process_sp;
1726 }
1727 
1728 ThreadSP StackFrame::CalculateThread() { return GetThread(); }
1729 
1730 StackFrameSP StackFrame::CalculateStackFrame() { return shared_from_this(); }
1731 
1732 void StackFrame::CalculateExecutionContext(ExecutionContext &exe_ctx) {
1733   exe_ctx.SetContext(shared_from_this());
1734 }
1735 
1736 void StackFrame::DumpUsingSettingsFormat(Stream *strm,
1737                                          const char *frame_marker) {
1738   if (strm == nullptr)
1739     return;
1740 
1741   GetSymbolContext(eSymbolContextEverything);
1742   ExecutionContext exe_ctx(shared_from_this());
1743   StreamString s;
1744 
1745   if (frame_marker)
1746     s.PutCString(frame_marker);
1747 
1748   const FormatEntity::Entry *frame_format = nullptr;
1749   Target *target = exe_ctx.GetTargetPtr();
1750   if (target)
1751     frame_format = target->GetDebugger().GetFrameFormat();
1752   if (frame_format && FormatEntity::Format(*frame_format, s, &m_sc, &exe_ctx,
1753                                            nullptr, nullptr, false, false)) {
1754     strm->PutCString(s.GetString());
1755   } else {
1756     Dump(strm, true, false);
1757     strm->EOL();
1758   }
1759 }
1760 
1761 void StackFrame::Dump(Stream *strm, bool show_frame_index,
1762                       bool show_fullpaths) {
1763   if (strm == nullptr)
1764     return;
1765 
1766   if (show_frame_index)
1767     strm->Printf("frame #%u: ", m_frame_index);
1768   ExecutionContext exe_ctx(shared_from_this());
1769   Target *target = exe_ctx.GetTargetPtr();
1770   strm->Printf("0x%0*" PRIx64 " ",
1771                target ? (target->GetArchitecture().GetAddressByteSize() * 2)
1772                       : 16,
1773                GetFrameCodeAddress().GetLoadAddress(target));
1774   GetSymbolContext(eSymbolContextEverything);
1775   const bool show_module = true;
1776   const bool show_inline = true;
1777   const bool show_function_arguments = true;
1778   const bool show_function_name = true;
1779   m_sc.DumpStopContext(strm, exe_ctx.GetBestExecutionContextScope(),
1780                        GetFrameCodeAddress(), show_fullpaths, show_module,
1781                        show_inline, show_function_arguments,
1782                        show_function_name);
1783 }
1784 
1785 void StackFrame::UpdateCurrentFrameFromPreviousFrame(StackFrame &prev_frame) {
1786   std::lock_guard<std::recursive_mutex> guard(m_mutex);
1787   assert(GetStackID() ==
1788          prev_frame.GetStackID()); // TODO: remove this after some testing
1789   m_variable_list_sp = prev_frame.m_variable_list_sp;
1790   m_variable_list_value_objects.Swap(prev_frame.m_variable_list_value_objects);
1791   if (!m_disassembly.GetString().empty()) {
1792     m_disassembly.Clear();
1793     m_disassembly.PutCString(prev_frame.m_disassembly.GetString());
1794   }
1795 }
1796 
1797 void StackFrame::UpdatePreviousFrameFromCurrentFrame(StackFrame &curr_frame) {
1798   std::lock_guard<std::recursive_mutex> guard(m_mutex);
1799   assert(GetStackID() ==
1800          curr_frame.GetStackID());     // TODO: remove this after some testing
1801   m_id.SetPC(curr_frame.m_id.GetPC()); // Update the Stack ID PC value
1802   assert(GetThread() == curr_frame.GetThread());
1803   m_frame_index = curr_frame.m_frame_index;
1804   m_concrete_frame_index = curr_frame.m_concrete_frame_index;
1805   m_reg_context_sp = curr_frame.m_reg_context_sp;
1806   m_frame_code_addr = curr_frame.m_frame_code_addr;
1807   assert(!m_sc.target_sp || !curr_frame.m_sc.target_sp ||
1808          m_sc.target_sp.get() == curr_frame.m_sc.target_sp.get());
1809   assert(!m_sc.module_sp || !curr_frame.m_sc.module_sp ||
1810          m_sc.module_sp.get() == curr_frame.m_sc.module_sp.get());
1811   assert(m_sc.comp_unit == nullptr || curr_frame.m_sc.comp_unit == nullptr ||
1812          m_sc.comp_unit == curr_frame.m_sc.comp_unit);
1813   assert(m_sc.function == nullptr || curr_frame.m_sc.function == nullptr ||
1814          m_sc.function == curr_frame.m_sc.function);
1815   m_sc = curr_frame.m_sc;
1816   m_flags.Clear(GOT_FRAME_BASE | eSymbolContextEverything);
1817   m_flags.Set(m_sc.GetResolvedMask());
1818   m_frame_base.Clear();
1819   m_frame_base_error.Clear();
1820 }
1821 
1822 bool StackFrame::HasCachedData() const {
1823   if (m_variable_list_sp)
1824     return true;
1825   if (m_variable_list_value_objects.GetSize() > 0)
1826     return true;
1827   if (!m_disassembly.GetString().empty())
1828     return true;
1829   return false;
1830 }
1831 
1832 bool StackFrame::GetStatus(Stream &strm, bool show_frame_info, bool show_source,
1833                            const char *frame_marker) {
1834 
1835   if (show_frame_info) {
1836     strm.Indent();
1837     DumpUsingSettingsFormat(&strm, frame_marker);
1838   }
1839 
1840   if (show_source) {
1841     ExecutionContext exe_ctx(shared_from_this());
1842     bool have_source = false, have_debuginfo = false;
1843     Debugger::StopDisassemblyType disasm_display =
1844         Debugger::eStopDisassemblyTypeNever;
1845     Target *target = exe_ctx.GetTargetPtr();
1846     if (target) {
1847       Debugger &debugger = target->GetDebugger();
1848       const uint32_t source_lines_before =
1849           debugger.GetStopSourceLineCount(true);
1850       const uint32_t source_lines_after =
1851           debugger.GetStopSourceLineCount(false);
1852       disasm_display = debugger.GetStopDisassemblyDisplay();
1853 
1854       GetSymbolContext(eSymbolContextCompUnit | eSymbolContextLineEntry);
1855       if (m_sc.comp_unit && m_sc.line_entry.IsValid()) {
1856         have_debuginfo = true;
1857         if (source_lines_before > 0 || source_lines_after > 0) {
1858           size_t num_lines =
1859               target->GetSourceManager().DisplaySourceLinesWithLineNumbers(
1860                   m_sc.line_entry.file, m_sc.line_entry.line,
1861                   m_sc.line_entry.column, source_lines_before,
1862                   source_lines_after, "->", &strm);
1863           if (num_lines != 0)
1864             have_source = true;
1865           // TODO: Give here a one time warning if source file is missing.
1866         }
1867       }
1868       switch (disasm_display) {
1869       case Debugger::eStopDisassemblyTypeNever:
1870         break;
1871 
1872       case Debugger::eStopDisassemblyTypeNoDebugInfo:
1873         if (have_debuginfo)
1874           break;
1875         LLVM_FALLTHROUGH;
1876 
1877       case Debugger::eStopDisassemblyTypeNoSource:
1878         if (have_source)
1879           break;
1880         LLVM_FALLTHROUGH;
1881 
1882       case Debugger::eStopDisassemblyTypeAlways:
1883         if (target) {
1884           const uint32_t disasm_lines = debugger.GetDisassemblyLineCount();
1885           if (disasm_lines > 0) {
1886             const ArchSpec &target_arch = target->GetArchitecture();
1887             AddressRange pc_range;
1888             pc_range.GetBaseAddress() = GetFrameCodeAddress();
1889             pc_range.SetByteSize(disasm_lines *
1890                                  target_arch.GetMaximumOpcodeByteSize());
1891             const char *plugin_name = nullptr;
1892             const char *flavor = nullptr;
1893             const bool mixed_source_and_assembly = false;
1894             Disassembler::Disassemble(
1895                 target->GetDebugger(), target_arch, plugin_name, flavor,
1896                 exe_ctx, pc_range, disasm_lines, mixed_source_and_assembly, 0,
1897                 Disassembler::eOptionMarkPCAddress, strm);
1898           }
1899         }
1900         break;
1901       }
1902     }
1903   }
1904   return true;
1905 }
1906