1 //===-- ValueObjectPrinter.cpp --------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "lldb/DataFormatters/ValueObjectPrinter.h"
10 
11 #include "lldb/Core/ValueObject.h"
12 #include "lldb/DataFormatters/DataVisualization.h"
13 #include "lldb/Interpreter/CommandInterpreter.h"
14 #include "lldb/Target/Language.h"
15 #include "lldb/Target/Target.h"
16 #include "lldb/Utility/Stream.h"
17 
18 using namespace lldb;
19 using namespace lldb_private;
20 
ValueObjectPrinter(ValueObject * valobj,Stream * s)21 ValueObjectPrinter::ValueObjectPrinter(ValueObject *valobj, Stream *s) {
22   if (valobj) {
23     DumpValueObjectOptions options(*valobj);
24     Init(valobj, s, options, m_options.m_max_ptr_depth, 0, nullptr);
25   } else {
26     DumpValueObjectOptions options;
27     Init(valobj, s, options, m_options.m_max_ptr_depth, 0, nullptr);
28   }
29 }
30 
ValueObjectPrinter(ValueObject * valobj,Stream * s,const DumpValueObjectOptions & options)31 ValueObjectPrinter::ValueObjectPrinter(ValueObject *valobj, Stream *s,
32                                        const DumpValueObjectOptions &options) {
33   Init(valobj, s, options, m_options.m_max_ptr_depth, 0, nullptr);
34 }
35 
ValueObjectPrinter(ValueObject * valobj,Stream * s,const DumpValueObjectOptions & options,const DumpValueObjectOptions::PointerDepth & ptr_depth,uint32_t curr_depth,InstancePointersSetSP printed_instance_pointers)36 ValueObjectPrinter::ValueObjectPrinter(
37     ValueObject *valobj, Stream *s, const DumpValueObjectOptions &options,
38     const DumpValueObjectOptions::PointerDepth &ptr_depth, uint32_t curr_depth,
39     InstancePointersSetSP printed_instance_pointers) {
40   Init(valobj, s, options, ptr_depth, curr_depth, printed_instance_pointers);
41 }
42 
Init(ValueObject * valobj,Stream * s,const DumpValueObjectOptions & options,const DumpValueObjectOptions::PointerDepth & ptr_depth,uint32_t curr_depth,InstancePointersSetSP printed_instance_pointers)43 void ValueObjectPrinter::Init(
44     ValueObject *valobj, Stream *s, const DumpValueObjectOptions &options,
45     const DumpValueObjectOptions::PointerDepth &ptr_depth, uint32_t curr_depth,
46     InstancePointersSetSP printed_instance_pointers) {
47   m_orig_valobj = valobj;
48   m_valobj = nullptr;
49   m_stream = s;
50   m_options = options;
51   m_ptr_depth = ptr_depth;
52   m_curr_depth = curr_depth;
53   assert(m_orig_valobj && "cannot print a NULL ValueObject");
54   assert(m_stream && "cannot print to a NULL Stream");
55   m_should_print = eLazyBoolCalculate;
56   m_is_nil = eLazyBoolCalculate;
57   m_is_uninit = eLazyBoolCalculate;
58   m_is_ptr = eLazyBoolCalculate;
59   m_is_ref = eLazyBoolCalculate;
60   m_is_aggregate = eLazyBoolCalculate;
61   m_is_instance_ptr = eLazyBoolCalculate;
62   m_summary_formatter = {nullptr, false};
63   m_value.assign("");
64   m_summary.assign("");
65   m_error.assign("");
66   m_val_summary_ok = false;
67   m_printed_instance_pointers =
68       printed_instance_pointers
69           ? printed_instance_pointers
70           : InstancePointersSetSP(new InstancePointersSet());
71 }
72 
PrintValueObject()73 bool ValueObjectPrinter::PrintValueObject() {
74   if (!GetMostSpecializedValue() || m_valobj == nullptr)
75     return false;
76 
77   if (ShouldPrintValueObject()) {
78     PrintLocationIfNeeded();
79     m_stream->Indent();
80 
81     PrintDecl();
82   }
83 
84   bool value_printed = false;
85   bool summary_printed = false;
86 
87   m_val_summary_ok =
88       PrintValueAndSummaryIfNeeded(value_printed, summary_printed);
89 
90   if (m_val_summary_ok)
91     PrintChildrenIfNeeded(value_printed, summary_printed);
92   else
93     m_stream->EOL();
94 
95   return true;
96 }
97 
GetMostSpecializedValue()98 bool ValueObjectPrinter::GetMostSpecializedValue() {
99   if (m_valobj)
100     return true;
101   bool update_success = m_orig_valobj->UpdateValueIfNeeded(true);
102   if (!update_success) {
103     m_valobj = m_orig_valobj;
104   } else {
105     if (m_orig_valobj->IsDynamic()) {
106       if (m_options.m_use_dynamic == eNoDynamicValues) {
107         ValueObject *static_value = m_orig_valobj->GetStaticValue().get();
108         if (static_value)
109           m_valobj = static_value;
110         else
111           m_valobj = m_orig_valobj;
112       } else
113         m_valobj = m_orig_valobj;
114     } else {
115       if (m_options.m_use_dynamic != eNoDynamicValues) {
116         ValueObject *dynamic_value =
117             m_orig_valobj->GetDynamicValue(m_options.m_use_dynamic).get();
118         if (dynamic_value)
119           m_valobj = dynamic_value;
120         else
121           m_valobj = m_orig_valobj;
122       } else
123         m_valobj = m_orig_valobj;
124     }
125 
126     if (m_valobj->IsSynthetic()) {
127       if (!m_options.m_use_synthetic) {
128         ValueObject *non_synthetic = m_valobj->GetNonSyntheticValue().get();
129         if (non_synthetic)
130           m_valobj = non_synthetic;
131       }
132     } else {
133       if (m_options.m_use_synthetic) {
134         ValueObject *synthetic = m_valobj->GetSyntheticValue().get();
135         if (synthetic)
136           m_valobj = synthetic;
137       }
138     }
139   }
140   m_compiler_type = m_valobj->GetCompilerType();
141   m_type_flags = m_compiler_type.GetTypeInfo();
142   return true;
143 }
144 
GetDescriptionForDisplay()145 const char *ValueObjectPrinter::GetDescriptionForDisplay() {
146   const char *str = m_valobj->GetObjectDescription();
147   if (!str)
148     str = m_valobj->GetSummaryAsCString();
149   if (!str)
150     str = m_valobj->GetValueAsCString();
151   return str;
152 }
153 
GetRootNameForDisplay()154 const char *ValueObjectPrinter::GetRootNameForDisplay() {
155   const char *root_valobj_name = m_options.m_root_valobj_name.empty()
156                                      ? m_valobj->GetName().AsCString()
157                                      : m_options.m_root_valobj_name.c_str();
158   return root_valobj_name ? root_valobj_name : "";
159 }
160 
ShouldPrintValueObject()161 bool ValueObjectPrinter::ShouldPrintValueObject() {
162   if (m_should_print == eLazyBoolCalculate)
163     m_should_print =
164         (!m_options.m_flat_output || m_type_flags.Test(eTypeHasValue))
165             ? eLazyBoolYes
166             : eLazyBoolNo;
167   return m_should_print == eLazyBoolYes;
168 }
169 
IsNil()170 bool ValueObjectPrinter::IsNil() {
171   if (m_is_nil == eLazyBoolCalculate)
172     m_is_nil = m_valobj->IsNilReference() ? eLazyBoolYes : eLazyBoolNo;
173   return m_is_nil == eLazyBoolYes;
174 }
175 
IsUninitialized()176 bool ValueObjectPrinter::IsUninitialized() {
177   if (m_is_uninit == eLazyBoolCalculate)
178     m_is_uninit =
179         m_valobj->IsUninitializedReference() ? eLazyBoolYes : eLazyBoolNo;
180   return m_is_uninit == eLazyBoolYes;
181 }
182 
IsPtr()183 bool ValueObjectPrinter::IsPtr() {
184   if (m_is_ptr == eLazyBoolCalculate)
185     m_is_ptr = m_type_flags.Test(eTypeIsPointer) ? eLazyBoolYes : eLazyBoolNo;
186   return m_is_ptr == eLazyBoolYes;
187 }
188 
IsRef()189 bool ValueObjectPrinter::IsRef() {
190   if (m_is_ref == eLazyBoolCalculate)
191     m_is_ref = m_type_flags.Test(eTypeIsReference) ? eLazyBoolYes : eLazyBoolNo;
192   return m_is_ref == eLazyBoolYes;
193 }
194 
IsAggregate()195 bool ValueObjectPrinter::IsAggregate() {
196   if (m_is_aggregate == eLazyBoolCalculate)
197     m_is_aggregate =
198         m_type_flags.Test(eTypeHasChildren) ? eLazyBoolYes : eLazyBoolNo;
199   return m_is_aggregate == eLazyBoolYes;
200 }
201 
IsInstancePointer()202 bool ValueObjectPrinter::IsInstancePointer() {
203   // you need to do this check on the value's clang type
204   if (m_is_instance_ptr == eLazyBoolCalculate)
205     m_is_instance_ptr = (m_valobj->GetValue().GetCompilerType().GetTypeInfo() &
206                          eTypeInstanceIsPointer) != 0
207                             ? eLazyBoolYes
208                             : eLazyBoolNo;
209   if ((eLazyBoolYes == m_is_instance_ptr) && m_valobj->IsBaseClass())
210     m_is_instance_ptr = eLazyBoolNo;
211   return m_is_instance_ptr == eLazyBoolYes;
212 }
213 
PrintLocationIfNeeded()214 bool ValueObjectPrinter::PrintLocationIfNeeded() {
215   if (m_options.m_show_location) {
216     m_stream->Printf("%s: ", m_valobj->GetLocationAsCString());
217     return true;
218   }
219   return false;
220 }
221 
PrintDecl()222 void ValueObjectPrinter::PrintDecl() {
223   bool show_type = true;
224   // if we are at the root-level and been asked to hide the root's type, then
225   // hide it
226   if (m_curr_depth == 0 && m_options.m_hide_root_type)
227     show_type = false;
228   else
229     // otherwise decide according to the usual rules (asked to show types -
230     // always at the root level)
231     show_type = m_options.m_show_types ||
232                 (m_curr_depth == 0 && !m_options.m_flat_output);
233 
234   StreamString typeName;
235 
236   // always show the type at the root level if it is invalid
237   if (show_type) {
238     // Some ValueObjects don't have types (like registers sets). Only print the
239     // type if there is one to print
240     ConstString type_name;
241     if (m_compiler_type.IsValid()) {
242       type_name = m_options.m_use_type_display_name
243                       ? m_valobj->GetDisplayTypeName()
244                       : m_valobj->GetQualifiedTypeName();
245     } else {
246       // only show an invalid type name if the user explicitly triggered
247       // show_type
248       if (m_options.m_show_types)
249         type_name = ConstString("<invalid type>");
250     }
251 
252     if (type_name) {
253       std::string type_name_str(type_name.GetCString());
254       if (m_options.m_hide_pointer_value) {
255         for (auto iter = type_name_str.find(" *"); iter != std::string::npos;
256              iter = type_name_str.find(" *")) {
257           type_name_str.erase(iter, 2);
258         }
259       }
260       typeName << type_name_str.c_str();
261     }
262   }
263 
264   StreamString varName;
265 
266   if (!m_options.m_hide_name) {
267     if (m_options.m_flat_output)
268       m_valobj->GetExpressionPath(varName);
269     else
270       varName << GetRootNameForDisplay();
271   }
272 
273   bool decl_printed = false;
274   if (!m_options.m_decl_printing_helper) {
275     // if the user didn't give us a custom helper, pick one based upon the
276     // language, either the one that this printer is bound to, or the preferred
277     // one for the ValueObject
278     lldb::LanguageType lang_type =
279         (m_options.m_varformat_language == lldb::eLanguageTypeUnknown)
280             ? m_valobj->GetPreferredDisplayLanguage()
281             : m_options.m_varformat_language;
282     if (Language *lang_plugin = Language::FindPlugin(lang_type)) {
283       m_options.m_decl_printing_helper = lang_plugin->GetDeclPrintingHelper();
284     }
285   }
286 
287   if (m_options.m_decl_printing_helper) {
288     ConstString type_name_cstr(typeName.GetString());
289     ConstString var_name_cstr(varName.GetString());
290 
291     StreamString dest_stream;
292     if (m_options.m_decl_printing_helper(type_name_cstr, var_name_cstr,
293                                          m_options, dest_stream)) {
294       decl_printed = true;
295       m_stream->PutCString(dest_stream.GetString());
296     }
297   }
298 
299   // if the helper failed, or there is none, do a default thing
300   if (!decl_printed) {
301     if (!typeName.Empty())
302       m_stream->Printf("(%s) ", typeName.GetData());
303     if (!varName.Empty())
304       m_stream->Printf("%s =", varName.GetData());
305     else if (!m_options.m_hide_name)
306       m_stream->Printf(" =");
307   }
308 }
309 
CheckScopeIfNeeded()310 bool ValueObjectPrinter::CheckScopeIfNeeded() {
311   if (m_options.m_scope_already_checked)
312     return true;
313   return m_valobj->IsInScope();
314 }
315 
GetSummaryFormatter(bool null_if_omitted)316 TypeSummaryImpl *ValueObjectPrinter::GetSummaryFormatter(bool null_if_omitted) {
317   if (!m_summary_formatter.second) {
318     TypeSummaryImpl *entry = m_options.m_summary_sp
319                                  ? m_options.m_summary_sp.get()
320                                  : m_valobj->GetSummaryFormat().get();
321 
322     if (m_options.m_omit_summary_depth > 0)
323       entry = nullptr;
324     m_summary_formatter.first = entry;
325     m_summary_formatter.second = true;
326   }
327   if (m_options.m_omit_summary_depth > 0 && null_if_omitted)
328     return nullptr;
329   return m_summary_formatter.first;
330 }
331 
IsPointerValue(const CompilerType & type)332 static bool IsPointerValue(const CompilerType &type) {
333   Flags type_flags(type.GetTypeInfo());
334   if (type_flags.AnySet(eTypeInstanceIsPointer | eTypeIsPointer))
335     return type_flags.AllClear(eTypeIsBuiltIn);
336   return false;
337 }
338 
GetValueSummaryError(std::string & value,std::string & summary,std::string & error)339 void ValueObjectPrinter::GetValueSummaryError(std::string &value,
340                                               std::string &summary,
341                                               std::string &error) {
342   lldb::Format format = m_options.m_format;
343   // if I am printing synthetized elements, apply the format to those elements
344   // only
345   if (m_options.m_pointer_as_array)
346     m_valobj->GetValueAsCString(lldb::eFormatDefault, value);
347   else if (format != eFormatDefault && format != m_valobj->GetFormat())
348     m_valobj->GetValueAsCString(format, value);
349   else {
350     const char *val_cstr = m_valobj->GetValueAsCString();
351     if (val_cstr)
352       value.assign(val_cstr);
353   }
354   const char *err_cstr = m_valobj->GetError().AsCString();
355   if (err_cstr)
356     error.assign(err_cstr);
357 
358   if (ShouldPrintValueObject()) {
359     if (IsNil())
360       summary.assign("nil");
361     else if (IsUninitialized())
362       summary.assign("<uninitialized>");
363     else if (m_options.m_omit_summary_depth == 0) {
364       TypeSummaryImpl *entry = GetSummaryFormatter();
365       if (entry)
366         m_valobj->GetSummaryAsCString(entry, summary,
367                                       m_options.m_varformat_language);
368       else {
369         const char *sum_cstr =
370             m_valobj->GetSummaryAsCString(m_options.m_varformat_language);
371         if (sum_cstr)
372           summary.assign(sum_cstr);
373       }
374     }
375   }
376 }
377 
PrintValueAndSummaryIfNeeded(bool & value_printed,bool & summary_printed)378 bool ValueObjectPrinter::PrintValueAndSummaryIfNeeded(bool &value_printed,
379                                                       bool &summary_printed) {
380   bool error_printed = false;
381   if (ShouldPrintValueObject()) {
382     if (!CheckScopeIfNeeded())
383       m_error.assign("out of scope");
384     if (m_error.empty()) {
385       GetValueSummaryError(m_value, m_summary, m_error);
386     }
387     if (m_error.size()) {
388       // we need to support scenarios in which it is actually fine for a value
389       // to have no type but - on the other hand - if we get an error *AND*
390       // have no type, we try to get out gracefully, since most often that
391       // combination means "could not resolve a type" and the default failure
392       // mode is quite ugly
393       if (!m_compiler_type.IsValid()) {
394         m_stream->Printf(" <could not resolve type>");
395         return false;
396       }
397 
398       error_printed = true;
399       m_stream->Printf(" <%s>\n", m_error.c_str());
400     } else {
401       // Make sure we have a value and make sure the summary didn't specify
402       // that the value should not be printed - and do not print the value if
403       // this thing is nil (but show the value if the user passes a format
404       // explicitly)
405       TypeSummaryImpl *entry = GetSummaryFormatter();
406       if (!IsNil() && !IsUninitialized() && !m_value.empty() &&
407           (entry == nullptr ||
408            (entry->DoesPrintValue(m_valobj) ||
409             m_options.m_format != eFormatDefault) ||
410            m_summary.empty()) &&
411           !m_options.m_hide_value) {
412         if (m_options.m_hide_pointer_value &&
413             IsPointerValue(m_valobj->GetCompilerType())) {
414         } else {
415           m_stream->Printf(" %s", m_value.c_str());
416           value_printed = true;
417         }
418       }
419 
420       if (m_summary.size()) {
421         m_stream->Printf(" %s", m_summary.c_str());
422         summary_printed = true;
423       }
424     }
425   }
426   return !error_printed;
427 }
428 
PrintObjectDescriptionIfNeeded(bool value_printed,bool summary_printed)429 bool ValueObjectPrinter::PrintObjectDescriptionIfNeeded(bool value_printed,
430                                                         bool summary_printed) {
431   if (ShouldPrintValueObject()) {
432     // let's avoid the overly verbose no description error for a nil thing
433     if (m_options.m_use_objc && !IsNil() && !IsUninitialized() &&
434         (!m_options.m_pointer_as_array)) {
435       if (!m_options.m_hide_value || !m_options.m_hide_name)
436         m_stream->Printf(" ");
437       const char *object_desc = nullptr;
438       if (value_printed || summary_printed)
439         object_desc = m_valobj->GetObjectDescription();
440       else
441         object_desc = GetDescriptionForDisplay();
442       if (object_desc && *object_desc) {
443         // If the description already ends with a \n don't add another one.
444         size_t object_end = strlen(object_desc) - 1;
445         if (object_desc[object_end] == '\n')
446           m_stream->Printf("%s", object_desc);
447         else
448           m_stream->Printf("%s\n", object_desc);
449         return true;
450       } else if (!value_printed && !summary_printed)
451         return true;
452       else
453         return false;
454     }
455   }
456   return true;
457 }
458 
CanAllowExpansion() const459 bool DumpValueObjectOptions::PointerDepth::CanAllowExpansion() const {
460   switch (m_mode) {
461   case Mode::Always:
462   case Mode::Default:
463     return m_count > 0;
464   case Mode::Never:
465     return false;
466   }
467   return false;
468 }
469 
ShouldPrintChildren(bool is_failed_description,DumpValueObjectOptions::PointerDepth & curr_ptr_depth)470 bool ValueObjectPrinter::ShouldPrintChildren(
471     bool is_failed_description,
472     DumpValueObjectOptions::PointerDepth &curr_ptr_depth) {
473   const bool is_ref = IsRef();
474   const bool is_ptr = IsPtr();
475   const bool is_uninit = IsUninitialized();
476 
477   if (is_uninit)
478     return false;
479 
480   // if the user has specified an element count, always print children as it is
481   // explicit user demand being honored
482   if (m_options.m_pointer_as_array)
483     return true;
484 
485   TypeSummaryImpl *entry = GetSummaryFormatter();
486 
487   if (m_options.m_use_objc)
488     return false;
489 
490   if (is_failed_description || m_curr_depth < m_options.m_max_depth) {
491     // We will show children for all concrete types. We won't show pointer
492     // contents unless a pointer depth has been specified. We won't reference
493     // contents unless the reference is the root object (depth of zero).
494 
495     // Use a new temporary pointer depth in case we override the current
496     // pointer depth below...
497 
498     if (is_ptr || is_ref) {
499       // We have a pointer or reference whose value is an address. Make sure
500       // that address is not NULL
501       AddressType ptr_address_type;
502       if (m_valobj->GetPointerValue(&ptr_address_type) == 0)
503         return false;
504 
505       const bool is_root_level = m_curr_depth == 0;
506 
507       if (is_ref && is_root_level) {
508         // If this is the root object (depth is zero) that we are showing and
509         // it is a reference, and no pointer depth has been supplied print out
510         // what it references. Don't do this at deeper depths otherwise we can
511         // end up with infinite recursion...
512         return true;
513       }
514 
515       return curr_ptr_depth.CanAllowExpansion();
516     }
517 
518     return (!entry || entry->DoesPrintChildren(m_valobj) || m_summary.empty());
519   }
520   return false;
521 }
522 
ShouldExpandEmptyAggregates()523 bool ValueObjectPrinter::ShouldExpandEmptyAggregates() {
524   TypeSummaryImpl *entry = GetSummaryFormatter();
525 
526   if (!entry)
527     return true;
528 
529   return entry->DoesPrintEmptyAggregates();
530 }
531 
GetValueObjectForChildrenGeneration()532 ValueObject *ValueObjectPrinter::GetValueObjectForChildrenGeneration() {
533   return m_valobj;
534 }
535 
PrintChildrenPreamble()536 void ValueObjectPrinter::PrintChildrenPreamble() {
537   if (m_options.m_flat_output) {
538     if (ShouldPrintValueObject())
539       m_stream->EOL();
540   } else {
541     if (ShouldPrintValueObject())
542       m_stream->PutCString(IsRef() ? ": {\n" : " {\n");
543     m_stream->IndentMore();
544   }
545 }
546 
PrintChild(ValueObjectSP child_sp,const DumpValueObjectOptions::PointerDepth & curr_ptr_depth)547 void ValueObjectPrinter::PrintChild(
548     ValueObjectSP child_sp,
549     const DumpValueObjectOptions::PointerDepth &curr_ptr_depth) {
550   const uint32_t consumed_depth = (!m_options.m_pointer_as_array) ? 1 : 0;
551   const bool does_consume_ptr_depth =
552       ((IsPtr() && !m_options.m_pointer_as_array) || IsRef());
553 
554   DumpValueObjectOptions child_options(m_options);
555   child_options.SetFormat(m_options.m_format)
556       .SetSummary()
557       .SetRootValueObjectName();
558   child_options.SetScopeChecked(true)
559       .SetHideName(m_options.m_hide_name)
560       .SetHideValue(m_options.m_hide_value)
561       .SetOmitSummaryDepth(child_options.m_omit_summary_depth > 1
562                                ? child_options.m_omit_summary_depth -
563                                      consumed_depth
564                                : 0)
565       .SetElementCount(0);
566 
567   if (child_sp.get()) {
568     ValueObjectPrinter child_printer(
569         child_sp.get(), m_stream, child_options,
570         does_consume_ptr_depth ? --curr_ptr_depth : curr_ptr_depth,
571         m_curr_depth + consumed_depth, m_printed_instance_pointers);
572     child_printer.PrintValueObject();
573   }
574 }
575 
GetMaxNumChildrenToPrint(bool & print_dotdotdot)576 uint32_t ValueObjectPrinter::GetMaxNumChildrenToPrint(bool &print_dotdotdot) {
577   ValueObject *synth_m_valobj = GetValueObjectForChildrenGeneration();
578 
579   if (m_options.m_pointer_as_array)
580     return m_options.m_pointer_as_array.m_element_count;
581 
582   size_t num_children = synth_m_valobj->GetNumChildren();
583   print_dotdotdot = false;
584   if (num_children) {
585     const size_t max_num_children =
586         m_valobj->GetTargetSP()->GetMaximumNumberOfChildrenToDisplay();
587 
588     if (num_children > max_num_children && !m_options.m_ignore_cap) {
589       print_dotdotdot = true;
590       return max_num_children;
591     }
592   }
593   return num_children;
594 }
595 
PrintChildrenPostamble(bool print_dotdotdot)596 void ValueObjectPrinter::PrintChildrenPostamble(bool print_dotdotdot) {
597   if (!m_options.m_flat_output) {
598     if (print_dotdotdot) {
599       m_valobj->GetTargetSP()
600           ->GetDebugger()
601           .GetCommandInterpreter()
602           .ChildrenTruncated();
603       m_stream->Indent("...\n");
604     }
605     m_stream->IndentLess();
606     m_stream->Indent("}\n");
607   }
608 }
609 
ShouldPrintEmptyBrackets(bool value_printed,bool summary_printed)610 bool ValueObjectPrinter::ShouldPrintEmptyBrackets(bool value_printed,
611                                                   bool summary_printed) {
612   ValueObject *synth_m_valobj = GetValueObjectForChildrenGeneration();
613 
614   if (!IsAggregate())
615     return false;
616 
617   if (!m_options.m_reveal_empty_aggregates) {
618     if (value_printed || summary_printed)
619       return false;
620   }
621 
622   if (synth_m_valobj->MightHaveChildren())
623     return true;
624 
625   if (m_val_summary_ok)
626     return false;
627 
628   return true;
629 }
630 
PhysicalIndexForLogicalIndex(size_t base,size_t stride,size_t logical)631 static constexpr size_t PhysicalIndexForLogicalIndex(size_t base, size_t stride,
632                                                      size_t logical) {
633   return base + logical * stride;
634 }
635 
GenerateChild(ValueObject * synth_valobj,size_t idx)636 ValueObjectSP ValueObjectPrinter::GenerateChild(ValueObject *synth_valobj,
637                                                 size_t idx) {
638   if (m_options.m_pointer_as_array) {
639     // if generating pointer-as-array children, use GetSyntheticArrayMember
640     return synth_valobj->GetSyntheticArrayMember(
641         PhysicalIndexForLogicalIndex(
642             m_options.m_pointer_as_array.m_base_element,
643             m_options.m_pointer_as_array.m_stride, idx),
644         true);
645   } else {
646     // otherwise, do the usual thing
647     return synth_valobj->GetChildAtIndex(idx, true);
648   }
649 }
650 
PrintChildren(bool value_printed,bool summary_printed,const DumpValueObjectOptions::PointerDepth & curr_ptr_depth)651 void ValueObjectPrinter::PrintChildren(
652     bool value_printed, bool summary_printed,
653     const DumpValueObjectOptions::PointerDepth &curr_ptr_depth) {
654   ValueObject *synth_m_valobj = GetValueObjectForChildrenGeneration();
655 
656   bool print_dotdotdot = false;
657   size_t num_children = GetMaxNumChildrenToPrint(print_dotdotdot);
658   if (num_children) {
659     bool any_children_printed = false;
660 
661     for (size_t idx = 0; idx < num_children; ++idx) {
662       if (ValueObjectSP child_sp = GenerateChild(synth_m_valobj, idx)) {
663         if (!any_children_printed) {
664           PrintChildrenPreamble();
665           any_children_printed = true;
666         }
667         PrintChild(child_sp, curr_ptr_depth);
668       }
669     }
670 
671     if (any_children_printed)
672       PrintChildrenPostamble(print_dotdotdot);
673     else {
674       if (ShouldPrintEmptyBrackets(value_printed, summary_printed)) {
675         if (ShouldPrintValueObject())
676           m_stream->PutCString(" {}\n");
677         else
678           m_stream->EOL();
679       } else
680         m_stream->EOL();
681     }
682   } else if (ShouldPrintEmptyBrackets(value_printed, summary_printed)) {
683     // Aggregate, no children...
684     if (ShouldPrintValueObject()) {
685       // if it has a synthetic value, then don't print {}, the synthetic
686       // children are probably only being used to vend a value
687       if (m_valobj->DoesProvideSyntheticValue() ||
688           !ShouldExpandEmptyAggregates())
689         m_stream->PutCString("\n");
690       else
691         m_stream->PutCString(" {}\n");
692     }
693   } else {
694     if (ShouldPrintValueObject())
695       m_stream->EOL();
696   }
697 }
698 
PrintChildrenOneLiner(bool hide_names)699 bool ValueObjectPrinter::PrintChildrenOneLiner(bool hide_names) {
700   if (!GetMostSpecializedValue() || m_valobj == nullptr)
701     return false;
702 
703   ValueObject *synth_m_valobj = GetValueObjectForChildrenGeneration();
704 
705   bool print_dotdotdot = false;
706   size_t num_children = GetMaxNumChildrenToPrint(print_dotdotdot);
707 
708   if (num_children) {
709     m_stream->PutChar('(');
710 
711     for (uint32_t idx = 0; idx < num_children; ++idx) {
712       lldb::ValueObjectSP child_sp(synth_m_valobj->GetChildAtIndex(idx, true));
713       if (child_sp)
714         child_sp = child_sp->GetQualifiedRepresentationIfAvailable(
715             m_options.m_use_dynamic, m_options.m_use_synthetic);
716       if (child_sp) {
717         if (idx)
718           m_stream->PutCString(", ");
719         if (!hide_names) {
720           const char *name = child_sp.get()->GetName().AsCString();
721           if (name && *name) {
722             m_stream->PutCString(name);
723             m_stream->PutCString(" = ");
724           }
725         }
726         child_sp->DumpPrintableRepresentation(
727             *m_stream, ValueObject::eValueObjectRepresentationStyleSummary,
728             m_options.m_format,
729             ValueObject::PrintableRepresentationSpecialCases::eDisable);
730       }
731     }
732 
733     if (print_dotdotdot)
734       m_stream->PutCString(", ...)");
735     else
736       m_stream->PutChar(')');
737   }
738   return true;
739 }
740 
PrintChildrenIfNeeded(bool value_printed,bool summary_printed)741 void ValueObjectPrinter::PrintChildrenIfNeeded(bool value_printed,
742                                                bool summary_printed) {
743   // This flag controls whether we tried to display a description for this
744   // object and failed if that happens, we want to display the children if any.
745   bool is_failed_description =
746       !PrintObjectDescriptionIfNeeded(value_printed, summary_printed);
747 
748   DumpValueObjectOptions::PointerDepth curr_ptr_depth = m_ptr_depth;
749   const bool print_children =
750       ShouldPrintChildren(is_failed_description, curr_ptr_depth);
751   const bool print_oneline =
752       (curr_ptr_depth.CanAllowExpansion() || m_options.m_show_types ||
753        !m_options.m_allow_oneliner_mode || m_options.m_flat_output ||
754        (m_options.m_pointer_as_array) || m_options.m_show_location)
755           ? false
756           : DataVisualization::ShouldPrintAsOneLiner(*m_valobj);
757   if (print_children && IsInstancePointer()) {
758     uint64_t instance_ptr_value = m_valobj->GetValueAsUnsigned(0);
759     if (m_printed_instance_pointers->count(instance_ptr_value)) {
760       // We already printed this instance-is-pointer thing, so don't expand it.
761       m_stream->PutCString(" {...}\n");
762       return;
763     } else {
764       // Remember this guy for future reference.
765       m_printed_instance_pointers->emplace(instance_ptr_value);
766     }
767   }
768 
769   if (print_children) {
770     if (print_oneline) {
771       m_stream->PutChar(' ');
772       PrintChildrenOneLiner(false);
773       m_stream->EOL();
774     } else
775       PrintChildren(value_printed, summary_printed, curr_ptr_depth);
776   } else if (m_curr_depth >= m_options.m_max_depth && IsAggregate() &&
777              ShouldPrintValueObject()) {
778     m_stream->PutCString("{...}\n");
779   } else
780     m_stream->EOL();
781 }
782