1 //===-- NSArray.cpp ---------------------------------------------*- C++ -*-===//
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 "clang/AST/ASTContext.h"
10 
11 #include "Cocoa.h"
12 
13 #include "Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.h"
14 
15 #include "lldb/Core/ValueObject.h"
16 #include "lldb/Core/ValueObjectConstResult.h"
17 #include "lldb/DataFormatters/FormattersHelpers.h"
18 #include "lldb/Expression/FunctionCaller.h"
19 #include "lldb/Symbol/ClangASTContext.h"
20 #include "lldb/Target/Language.h"
21 #include "lldb/Target/Target.h"
22 #include "lldb/Utility/DataBufferHeap.h"
23 #include "lldb/Utility/Endian.h"
24 #include "lldb/Utility/Status.h"
25 #include "lldb/Utility/Stream.h"
26 
27 using namespace lldb;
28 using namespace lldb_private;
29 using namespace lldb_private::formatters;
30 
31 namespace lldb_private {
32 namespace formatters {
33 std::map<ConstString, CXXFunctionSummaryFormat::Callback> &
34 NSArray_Additionals::GetAdditionalSummaries() {
35   static std::map<ConstString, CXXFunctionSummaryFormat::Callback> g_map;
36   return g_map;
37 }
38 
39 std::map<ConstString, CXXSyntheticChildren::CreateFrontEndCallback> &
40 NSArray_Additionals::GetAdditionalSynthetics() {
41   static std::map<ConstString, CXXSyntheticChildren::CreateFrontEndCallback>
42       g_map;
43   return g_map;
44 }
45 
46 class NSArrayMSyntheticFrontEndBase : public SyntheticChildrenFrontEnd {
47 public:
48   NSArrayMSyntheticFrontEndBase(lldb::ValueObjectSP valobj_sp);
49 
50   ~NSArrayMSyntheticFrontEndBase() override = default;
51 
52   size_t CalculateNumChildren() override;
53 
54   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
55 
56   bool Update() override = 0;
57 
58   bool MightHaveChildren() override;
59 
60   size_t GetIndexOfChildWithName(ConstString name) override;
61 
62 protected:
63   virtual lldb::addr_t GetDataAddress() = 0;
64 
65   virtual uint64_t GetUsedCount() = 0;
66 
67   virtual uint64_t GetOffset() = 0;
68 
69   virtual uint64_t GetSize() = 0;
70 
71   ExecutionContextRef m_exe_ctx_ref;
72   uint8_t m_ptr_size;
73   CompilerType m_id_type;
74 };
75 
76 template <typename D32, typename D64>
77 class GenericNSArrayMSyntheticFrontEnd : public NSArrayMSyntheticFrontEndBase {
78 public:
79   GenericNSArrayMSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);
80 
81   ~GenericNSArrayMSyntheticFrontEnd() override;
82 
83   bool Update() override;
84 
85 protected:
86   lldb::addr_t GetDataAddress() override;
87 
88   uint64_t GetUsedCount() override;
89 
90   uint64_t GetOffset() override;
91 
92   uint64_t GetSize() override;
93 
94 private:
95   D32 *m_data_32;
96   D64 *m_data_64;
97 };
98 
99 namespace Foundation109 {
100   struct DataDescriptor_32 {
101     uint32_t _used;
102     uint32_t _priv1 : 2;
103     uint32_t _size : 30;
104     uint32_t _priv2 : 2;
105     uint32_t _offset : 30;
106     uint32_t _priv3;
107     uint32_t _data;
108   };
109 
110   struct DataDescriptor_64 {
111     uint64_t _used;
112     uint64_t _priv1 : 2;
113     uint64_t _size : 62;
114     uint64_t _priv2 : 2;
115     uint64_t _offset : 62;
116     uint32_t _priv3;
117     uint64_t _data;
118   };
119 
120   using NSArrayMSyntheticFrontEnd =
121       GenericNSArrayMSyntheticFrontEnd<DataDescriptor_32, DataDescriptor_64>;
122 }
123 
124 namespace Foundation1010 {
125   struct DataDescriptor_32 {
126     uint32_t _used;
127     uint32_t _offset;
128     uint32_t _size : 28;
129     uint64_t _priv1 : 4;
130     uint32_t _priv2;
131     uint32_t _data;
132   };
133 
134   struct DataDescriptor_64 {
135     uint64_t _used;
136     uint64_t _offset;
137     uint64_t _size : 60;
138     uint64_t _priv1 : 4;
139     uint32_t _priv2;
140     uint64_t _data;
141   };
142 
143   using NSArrayMSyntheticFrontEnd =
144       GenericNSArrayMSyntheticFrontEnd<DataDescriptor_32, DataDescriptor_64>;
145 }
146 
147 namespace Foundation1428 {
148   struct DataDescriptor_32 {
149     uint32_t _used;
150     uint32_t _offset;
151     uint32_t _size;
152     uint32_t _data;
153   };
154 
155   struct DataDescriptor_64 {
156     uint64_t _used;
157     uint64_t _offset;
158     uint64_t _size;
159     uint64_t _data;
160   };
161 
162   using NSArrayMSyntheticFrontEnd =
163       GenericNSArrayMSyntheticFrontEnd<DataDescriptor_32, DataDescriptor_64>;
164 }
165 
166 namespace Foundation1437 {
167   template <typename PtrType>
168   struct DataDescriptor {
169     PtrType _cow;
170     // __deque
171     PtrType _data;
172     uint32_t _offset;
173     uint32_t _size;
174     uint32_t _muts;
175     uint32_t _used;
176   };
177 
178   using NSArrayMSyntheticFrontEnd =
179      GenericNSArrayMSyntheticFrontEnd<
180         DataDescriptor<uint32_t>, DataDescriptor<uint64_t>>;
181 
182   template <typename DD>
183   uint64_t
184   __NSArrayMSize_Impl(lldb_private::Process &process,
185                       lldb::addr_t valobj_addr, Status &error) {
186     const lldb::addr_t start_of_descriptor =
187     valobj_addr + process.GetAddressByteSize();
188     DD descriptor = DD();
189     process.ReadMemory(start_of_descriptor, &descriptor,
190                        sizeof(descriptor), error);
191     if (error.Fail()) {
192       return 0;
193     }
194     return descriptor._used;
195   }
196 
197   uint64_t
198   __NSArrayMSize(lldb_private::Process &process, lldb::addr_t valobj_addr,
199                  Status &error) {
200     if (process.GetAddressByteSize() == 4) {
201       return __NSArrayMSize_Impl<DataDescriptor<uint32_t>>(process, valobj_addr,
202                                                            error);
203     } else {
204       return __NSArrayMSize_Impl<DataDescriptor<uint64_t>>(process, valobj_addr,
205                                                            error);
206     }
207   }
208 
209 }
210 
211 namespace CallStackArray {
212 struct DataDescriptor_32 {
213   uint32_t _data;
214   uint32_t _used;
215   uint32_t _offset;
216   const uint32_t _size = 0;
217 };
218 
219 struct DataDescriptor_64 {
220   uint64_t _data;
221   uint64_t _used;
222   uint64_t _offset;
223   const uint64_t _size = 0;
224 };
225 
226 using NSCallStackArraySyntheticFrontEnd =
227     GenericNSArrayMSyntheticFrontEnd<DataDescriptor_32, DataDescriptor_64>;
228 } // namespace CallStackArray
229 
230 template <typename D32, typename D64, bool Inline>
231 class GenericNSArrayISyntheticFrontEnd : public SyntheticChildrenFrontEnd {
232 public:
233   GenericNSArrayISyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);
234 
235   ~GenericNSArrayISyntheticFrontEnd() override;
236 
237   size_t CalculateNumChildren() override;
238 
239   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
240 
241   bool Update() override;
242 
243   bool MightHaveChildren() override;
244 
245   size_t GetIndexOfChildWithName(ConstString name) override;
246 
247 private:
248   ExecutionContextRef m_exe_ctx_ref;
249   uint8_t m_ptr_size;
250 
251   D32 *m_data_32;
252   D64 *m_data_64;
253   CompilerType m_id_type;
254 };
255 
256 namespace Foundation1300 {
257     struct IDD32 {
258         uint32_t used;
259         uint32_t list;
260     };
261 
262     struct IDD64 {
263         uint64_t used;
264         uint64_t list;
265     };
266 
267     using NSArrayISyntheticFrontEnd =
268         GenericNSArrayISyntheticFrontEnd<IDD32, IDD64, true>;
269 }
270 
271 namespace Foundation1430 {
272     using NSArrayISyntheticFrontEnd =
273         Foundation1428::NSArrayMSyntheticFrontEnd;
274 }
275 
276 namespace Foundation1436 {
277     struct IDD32 {
278         uint32_t used;
279         uint32_t list; // in Inline cases, this is the first element
280     };
281 
282     struct IDD64 {
283         uint64_t used;
284         uint64_t list; // in Inline cases, this is the first element
285     };
286 
287     using NSArrayI_TransferSyntheticFrontEnd =
288         GenericNSArrayISyntheticFrontEnd<IDD32, IDD64, false>;
289 
290     using NSArrayISyntheticFrontEnd =
291         GenericNSArrayISyntheticFrontEnd<IDD32, IDD64, true>;
292 
293     using NSFrozenArrayMSyntheticFrontEnd =
294         Foundation1437::NSArrayMSyntheticFrontEnd;
295 
296     uint64_t
297     __NSFrozenArrayMSize(lldb_private::Process &process, lldb::addr_t valobj_addr,
298                          Status &error) {
299       return Foundation1437::__NSArrayMSize(process, valobj_addr, error);
300     }
301 }
302 
303 class NSArray0SyntheticFrontEnd : public SyntheticChildrenFrontEnd {
304 public:
305   NSArray0SyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);
306 
307   ~NSArray0SyntheticFrontEnd() override = default;
308 
309   size_t CalculateNumChildren() override;
310 
311   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
312 
313   bool Update() override;
314 
315   bool MightHaveChildren() override;
316 
317   size_t GetIndexOfChildWithName(ConstString name) override;
318 };
319 
320 class NSArray1SyntheticFrontEnd : public SyntheticChildrenFrontEnd {
321 public:
322   NSArray1SyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);
323 
324   ~NSArray1SyntheticFrontEnd() override = default;
325 
326   size_t CalculateNumChildren() override;
327 
328   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
329 
330   bool Update() override;
331 
332   bool MightHaveChildren() override;
333 
334   size_t GetIndexOfChildWithName(ConstString name) override;
335 };
336 } // namespace formatters
337 } // namespace lldb_private
338 
339 bool lldb_private::formatters::NSArraySummaryProvider(
340     ValueObject &valobj, Stream &stream, const TypeSummaryOptions &options) {
341   static ConstString g_TypeHint("NSArray");
342 
343   ProcessSP process_sp = valobj.GetProcessSP();
344   if (!process_sp)
345     return false;
346 
347   ObjCLanguageRuntime *runtime = ObjCLanguageRuntime::Get(*process_sp);
348 
349   if (!runtime)
350     return false;
351 
352   ObjCLanguageRuntime::ClassDescriptorSP descriptor(
353       runtime->GetClassDescriptor(valobj));
354 
355   if (!descriptor || !descriptor->IsValid())
356     return false;
357 
358   uint32_t ptr_size = process_sp->GetAddressByteSize();
359 
360   lldb::addr_t valobj_addr = valobj.GetValueAsUnsigned(0);
361 
362   if (!valobj_addr)
363     return false;
364 
365   uint64_t value = 0;
366 
367   ConstString class_name(descriptor->GetClassName());
368 
369   static const ConstString g_NSArrayI("__NSArrayI");
370   static const ConstString g_NSArrayM("__NSArrayM");
371   static const ConstString g_NSArrayI_Transfer("__NSArrayI_Transfer");
372   static const ConstString g_NSFrozenArrayM("__NSFrozenArrayM");
373   static const ConstString g_NSArray0("__NSArray0");
374   static const ConstString g_NSArray1("__NSSingleObjectArrayI");
375   static const ConstString g_NSArrayCF("__NSCFArray");
376   static const ConstString g_NSArrayMLegacy("__NSArrayM_Legacy");
377   static const ConstString g_NSArrayMImmutable("__NSArrayM_Immutable");
378   static const ConstString g_NSCallStackArray("_NSCallStackArray");
379 
380   if (class_name.IsEmpty())
381     return false;
382 
383   if (class_name == g_NSArrayI) {
384     Status error;
385     value = process_sp->ReadUnsignedIntegerFromMemory(valobj_addr + ptr_size,
386                                                       ptr_size, 0, error);
387     if (error.Fail())
388       return false;
389   } else if (class_name == g_NSArrayM) {
390     AppleObjCRuntime *apple_runtime =
391     llvm::dyn_cast_or_null<AppleObjCRuntime>(runtime);
392     Status error;
393     if (apple_runtime && apple_runtime->GetFoundationVersion() >= 1437) {
394       value = Foundation1437::__NSArrayMSize(*process_sp, valobj_addr, error);
395     } else {
396       value = process_sp->ReadUnsignedIntegerFromMemory(valobj_addr + ptr_size,
397                                                         ptr_size, 0, error);
398     }
399     if (error.Fail())
400       return false;
401   } else if (class_name == g_NSArrayI_Transfer) {
402     Status error;
403     value = process_sp->ReadUnsignedIntegerFromMemory(valobj_addr + ptr_size,
404                                                       ptr_size, 0, error);
405     if (error.Fail())
406       return false;
407   } else if (class_name == g_NSFrozenArrayM) {
408     Status error;
409     value = Foundation1436::__NSFrozenArrayMSize(*process_sp, valobj_addr, error);
410     if (error.Fail())
411       return false;
412   } else if (class_name == g_NSArrayMLegacy) {
413     Status error;
414     value = process_sp->ReadUnsignedIntegerFromMemory(valobj_addr + ptr_size,
415                                                       ptr_size, 0, error);
416     if (error.Fail())
417       return false;
418   } else if (class_name == g_NSArrayMImmutable) {
419     Status error;
420     value = process_sp->ReadUnsignedIntegerFromMemory(valobj_addr + ptr_size,
421                                                       ptr_size, 0, error);
422     if (error.Fail())
423       return false;
424   } else if (class_name == g_NSArray0) {
425     value = 0;
426   } else if (class_name == g_NSArray1) {
427     value = 1;
428   } else if (class_name == g_NSArrayCF || class_name == g_NSCallStackArray) {
429     // __NSCFArray and _NSCallStackArray store the number of elements as a
430     // pointer-sized value at offset `2 * ptr_size`.
431     Status error;
432     value = process_sp->ReadUnsignedIntegerFromMemory(
433         valobj_addr + 2 * ptr_size, ptr_size, 0, error);
434     if (error.Fail())
435       return false;
436   } else {
437     auto &map(NSArray_Additionals::GetAdditionalSummaries());
438     auto iter = map.find(class_name), end = map.end();
439     if (iter != end)
440       return iter->second(valobj, stream, options);
441     else
442       return false;
443   }
444 
445   std::string prefix, suffix;
446   if (Language *language = Language::FindPlugin(options.GetLanguage())) {
447     if (!language->GetFormatterPrefixSuffix(valobj, g_TypeHint, prefix,
448                                             suffix)) {
449       prefix.clear();
450       suffix.clear();
451     }
452   }
453 
454   stream.Printf("%s%" PRIu64 " %s%s%s", prefix.c_str(), value, "element",
455                 value == 1 ? "" : "s", suffix.c_str());
456   return true;
457 }
458 
459 lldb_private::formatters::NSArrayMSyntheticFrontEndBase::NSArrayMSyntheticFrontEndBase(
460     lldb::ValueObjectSP valobj_sp)
461     : SyntheticChildrenFrontEnd(*valobj_sp), m_exe_ctx_ref(), m_ptr_size(8),
462       m_id_type() {
463   if (valobj_sp) {
464     auto *clang_ast_context = ClangASTContext::GetScratch(
465         *valobj_sp->GetExecutionContextRef().GetTargetSP());
466     if (clang_ast_context)
467       m_id_type = CompilerType(
468           clang_ast_context,
469           clang_ast_context->getASTContext().ObjCBuiltinIdTy.getAsOpaquePtr());
470     if (valobj_sp->GetProcessSP())
471       m_ptr_size = valobj_sp->GetProcessSP()->GetAddressByteSize();
472   }
473 }
474 
475 template <typename D32, typename D64>
476 lldb_private::formatters::
477   GenericNSArrayMSyntheticFrontEnd<D32, D64>::
478     GenericNSArrayMSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
479     : NSArrayMSyntheticFrontEndBase(valobj_sp), m_data_32(nullptr),
480       m_data_64(nullptr) {}
481 
482 size_t
483 lldb_private::formatters::NSArrayMSyntheticFrontEndBase::CalculateNumChildren() {
484   return GetUsedCount();
485 }
486 
487 lldb::ValueObjectSP
488 lldb_private::formatters::NSArrayMSyntheticFrontEndBase::GetChildAtIndex(
489     size_t idx) {
490   if (idx >= CalculateNumChildren())
491     return lldb::ValueObjectSP();
492   lldb::addr_t object_at_idx = GetDataAddress();
493   size_t pyhs_idx = idx;
494   pyhs_idx += GetOffset();
495   if (GetSize() <= pyhs_idx)
496     pyhs_idx -= GetSize();
497   object_at_idx += (pyhs_idx * m_ptr_size);
498   StreamString idx_name;
499   idx_name.Printf("[%" PRIu64 "]", (uint64_t)idx);
500   return CreateValueObjectFromAddress(idx_name.GetString(), object_at_idx,
501                                       m_exe_ctx_ref, m_id_type);
502 }
503 
504 template <typename D32, typename D64>
505 bool
506 lldb_private::formatters::
507   GenericNSArrayMSyntheticFrontEnd<D32, D64>::Update() {
508   ValueObjectSP valobj_sp = m_backend.GetSP();
509   m_ptr_size = 0;
510   delete m_data_32;
511   m_data_32 = nullptr;
512   delete m_data_64;
513   m_data_64 = nullptr;
514   if (!valobj_sp)
515     return false;
516   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
517   Status error;
518   error.Clear();
519   lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
520   if (!process_sp)
521     return false;
522   m_ptr_size = process_sp->GetAddressByteSize();
523   uint64_t data_location = valobj_sp->GetValueAsUnsigned(0) + m_ptr_size;
524   if (m_ptr_size == 4) {
525     m_data_32 = new D32();
526     process_sp->ReadMemory(data_location, m_data_32, sizeof(D32),
527                            error);
528   } else {
529     m_data_64 = new D64();
530     process_sp->ReadMemory(data_location, m_data_64, sizeof(D64),
531                            error);
532   }
533   if (error.Fail())
534     return false;
535   return false;
536 }
537 
538 bool
539 lldb_private::formatters::NSArrayMSyntheticFrontEndBase::MightHaveChildren() {
540   return true;
541 }
542 
543 size_t
544 lldb_private::formatters::NSArrayMSyntheticFrontEndBase::GetIndexOfChildWithName(
545     ConstString name) {
546   const char *item_name = name.GetCString();
547   uint32_t idx = ExtractIndexFromString(item_name);
548   if (idx < UINT32_MAX && idx >= CalculateNumChildren())
549     return UINT32_MAX;
550   return idx;
551 }
552 
553 template <typename D32, typename D64>
554 lldb_private::formatters::
555   GenericNSArrayMSyntheticFrontEnd<D32, D64>::
556     ~GenericNSArrayMSyntheticFrontEnd() {
557   delete m_data_32;
558   m_data_32 = nullptr;
559   delete m_data_64;
560   m_data_64 = nullptr;
561 }
562 
563 template <typename D32, typename D64>
564 lldb::addr_t
565 lldb_private::formatters::
566   GenericNSArrayMSyntheticFrontEnd<D32, D64>::
567     GenericNSArrayMSyntheticFrontEnd::GetDataAddress() {
568   if (!m_data_32 && !m_data_64)
569     return LLDB_INVALID_ADDRESS;
570   return m_data_32 ? m_data_32->_data : m_data_64->_data;
571 }
572 
573 template <typename D32, typename D64>
574 uint64_t
575 lldb_private::formatters::
576   GenericNSArrayMSyntheticFrontEnd<D32, D64>::
577     GenericNSArrayMSyntheticFrontEnd::GetUsedCount() {
578   if (!m_data_32 && !m_data_64)
579     return 0;
580   return m_data_32 ? m_data_32->_used : m_data_64->_used;
581 }
582 
583 template <typename D32, typename D64>
584 uint64_t
585 lldb_private::formatters::
586   GenericNSArrayMSyntheticFrontEnd<D32, D64>::
587     GenericNSArrayMSyntheticFrontEnd::GetOffset() {
588   if (!m_data_32 && !m_data_64)
589     return 0;
590   return m_data_32 ? m_data_32->_offset : m_data_64->_offset;
591 }
592 
593 template <typename D32, typename D64>
594 uint64_t
595 lldb_private::formatters::
596   GenericNSArrayMSyntheticFrontEnd<D32, D64>::
597     GenericNSArrayMSyntheticFrontEnd::GetSize() {
598   if (!m_data_32 && !m_data_64)
599     return 0;
600   return m_data_32 ? m_data_32->_size : m_data_64->_size;
601 }
602 
603 template <typename D32, typename D64, bool Inline>
604 lldb_private::formatters::GenericNSArrayISyntheticFrontEnd<D32, D64, Inline>::
605   GenericNSArrayISyntheticFrontEnd(
606     lldb::ValueObjectSP valobj_sp)
607     : SyntheticChildrenFrontEnd(*valobj_sp), m_exe_ctx_ref(), m_ptr_size(8),
608       m_data_32(nullptr), m_data_64(nullptr) {
609   if (valobj_sp) {
610     CompilerType type = valobj_sp->GetCompilerType();
611     if (type) {
612       auto *clang_ast_context = ClangASTContext::GetScratch(
613           *valobj_sp->GetExecutionContextRef().GetTargetSP());
614       if (clang_ast_context)
615         m_id_type = clang_ast_context->GetType(
616             clang_ast_context->getASTContext().ObjCBuiltinIdTy);
617     }
618   }
619 }
620 
621 template <typename D32, typename D64, bool Inline>
622 lldb_private::formatters::GenericNSArrayISyntheticFrontEnd<D32, D64, Inline>::
623   ~GenericNSArrayISyntheticFrontEnd() {
624   delete m_data_32;
625   m_data_32 = nullptr;
626   delete m_data_64;
627   m_data_64 = nullptr;
628 }
629 
630 template <typename D32, typename D64, bool Inline>
631 size_t
632 lldb_private::formatters::GenericNSArrayISyntheticFrontEnd<D32, D64, Inline>::
633   GetIndexOfChildWithName(ConstString name) {
634   const char *item_name = name.GetCString();
635   uint32_t idx = ExtractIndexFromString(item_name);
636   if (idx < UINT32_MAX && idx >= CalculateNumChildren())
637     return UINT32_MAX;
638   return idx;
639 }
640 
641 template <typename D32, typename D64, bool Inline>
642 size_t
643 lldb_private::formatters::GenericNSArrayISyntheticFrontEnd<D32, D64, Inline>::
644   CalculateNumChildren() {
645   return m_data_32 ? m_data_32->used : m_data_64->used;
646 }
647 
648 template <typename D32, typename D64, bool Inline>
649 bool
650 lldb_private::formatters::GenericNSArrayISyntheticFrontEnd<D32, D64, Inline>::
651   Update() {
652   ValueObjectSP valobj_sp = m_backend.GetSP();
653   m_ptr_size = 0;
654   delete m_data_32;
655   m_data_32 = nullptr;
656   delete m_data_64;
657   m_data_64 = nullptr;
658   if (!valobj_sp)
659     return false;
660   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
661   Status error;
662   error.Clear();
663   lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
664   if (!process_sp)
665     return false;
666   m_ptr_size = process_sp->GetAddressByteSize();
667   uint64_t data_location = valobj_sp->GetValueAsUnsigned(0) + m_ptr_size;
668   if (m_ptr_size == 4) {
669     m_data_32 = new D32();
670     process_sp->ReadMemory(data_location, m_data_32, sizeof(D32),
671                            error);
672   } else {
673     m_data_64 = new D64();
674     process_sp->ReadMemory(data_location, m_data_64, sizeof(D64),
675                            error);
676   }
677   if (error.Fail())
678     return false;
679   return false;
680 }
681 
682 template <typename D32, typename D64, bool Inline>
683 bool
684 lldb_private::formatters::GenericNSArrayISyntheticFrontEnd<D32, D64, Inline>::
685   MightHaveChildren() {
686   return true;
687 }
688 
689 template <typename D32, typename D64, bool Inline>
690 lldb::ValueObjectSP
691 lldb_private::formatters::GenericNSArrayISyntheticFrontEnd<D32, D64, Inline>::
692   GetChildAtIndex(size_t idx) {
693   if (idx >= CalculateNumChildren())
694     return lldb::ValueObjectSP();
695   lldb::addr_t object_at_idx;
696   if (Inline) {
697     object_at_idx = m_backend.GetSP()->GetValueAsUnsigned(0) + m_ptr_size;
698     object_at_idx += m_ptr_size == 4 ? sizeof(D32) : sizeof(D64); // skip the data header
699     object_at_idx -= m_ptr_size; // we treat the last entry in the data header as the first pointer
700   } else {
701     object_at_idx = m_data_32 ? m_data_32->list : m_data_64->list;
702   }
703   object_at_idx += (idx * m_ptr_size);
704 
705   ProcessSP process_sp = m_exe_ctx_ref.GetProcessSP();
706   if (!process_sp)
707     return lldb::ValueObjectSP();
708   Status error;
709   if (error.Fail())
710     return lldb::ValueObjectSP();
711   StreamString idx_name;
712   idx_name.Printf("[%" PRIu64 "]", (uint64_t)idx);
713   return CreateValueObjectFromAddress(idx_name.GetString(), object_at_idx,
714                                       m_exe_ctx_ref, m_id_type);
715 }
716 
717 lldb_private::formatters::NSArray0SyntheticFrontEnd::NSArray0SyntheticFrontEnd(
718     lldb::ValueObjectSP valobj_sp)
719     : SyntheticChildrenFrontEnd(*valobj_sp) {}
720 
721 size_t
722 lldb_private::formatters::NSArray0SyntheticFrontEnd::GetIndexOfChildWithName(
723     ConstString name) {
724   return UINT32_MAX;
725 }
726 
727 size_t
728 lldb_private::formatters::NSArray0SyntheticFrontEnd::CalculateNumChildren() {
729   return 0;
730 }
731 
732 bool lldb_private::formatters::NSArray0SyntheticFrontEnd::Update() {
733   return false;
734 }
735 
736 bool lldb_private::formatters::NSArray0SyntheticFrontEnd::MightHaveChildren() {
737   return false;
738 }
739 
740 lldb::ValueObjectSP
741 lldb_private::formatters::NSArray0SyntheticFrontEnd::GetChildAtIndex(
742     size_t idx) {
743   return lldb::ValueObjectSP();
744 }
745 
746 lldb_private::formatters::NSArray1SyntheticFrontEnd::NSArray1SyntheticFrontEnd(
747     lldb::ValueObjectSP valobj_sp)
748     : SyntheticChildrenFrontEnd(*valobj_sp.get()) {}
749 
750 size_t
751 lldb_private::formatters::NSArray1SyntheticFrontEnd::GetIndexOfChildWithName(
752     ConstString name) {
753   static const ConstString g_zero("[0]");
754 
755   if (name == g_zero)
756     return 0;
757 
758   return UINT32_MAX;
759 }
760 
761 size_t
762 lldb_private::formatters::NSArray1SyntheticFrontEnd::CalculateNumChildren() {
763   return 1;
764 }
765 
766 bool lldb_private::formatters::NSArray1SyntheticFrontEnd::Update() {
767   return false;
768 }
769 
770 bool lldb_private::formatters::NSArray1SyntheticFrontEnd::MightHaveChildren() {
771   return true;
772 }
773 
774 lldb::ValueObjectSP
775 lldb_private::formatters::NSArray1SyntheticFrontEnd::GetChildAtIndex(
776     size_t idx) {
777   static const ConstString g_zero("[0]");
778 
779   if (idx == 0) {
780     auto *clang_ast_context =
781         ClangASTContext::GetScratch(*m_backend.GetTargetSP());
782     if (clang_ast_context) {
783       CompilerType id_type(
784           clang_ast_context->GetBasicType(lldb::eBasicTypeObjCID));
785       return m_backend.GetSyntheticChildAtOffset(
786           m_backend.GetProcessSP()->GetAddressByteSize(), id_type, true,
787           g_zero);
788     }
789   }
790   return lldb::ValueObjectSP();
791 }
792 
793 SyntheticChildrenFrontEnd *
794 lldb_private::formatters::NSArraySyntheticFrontEndCreator(
795     CXXSyntheticChildren *synth, lldb::ValueObjectSP valobj_sp) {
796   if (!valobj_sp)
797     return nullptr;
798 
799   lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
800   if (!process_sp)
801     return nullptr;
802   AppleObjCRuntime *runtime = llvm::dyn_cast_or_null<AppleObjCRuntime>(
803       ObjCLanguageRuntime::Get(*process_sp));
804   if (!runtime)
805     return nullptr;
806 
807   CompilerType valobj_type(valobj_sp->GetCompilerType());
808   Flags flags(valobj_type.GetTypeInfo());
809 
810   if (flags.IsClear(eTypeIsPointer)) {
811     Status error;
812     valobj_sp = valobj_sp->AddressOf(error);
813     if (error.Fail() || !valobj_sp)
814       return nullptr;
815   }
816 
817   ObjCLanguageRuntime::ClassDescriptorSP descriptor(
818       runtime->GetClassDescriptor(*valobj_sp));
819 
820   if (!descriptor || !descriptor->IsValid())
821     return nullptr;
822 
823   ConstString class_name(descriptor->GetClassName());
824 
825   static const ConstString g_NSArrayI("__NSArrayI");
826   static const ConstString g_NSArrayI_Transfer("__NSArrayI_Transfer");
827   static const ConstString g_NSFrozenArrayM("__NSFrozenArrayM");
828   static const ConstString g_NSArrayM("__NSArrayM");
829   static const ConstString g_NSArray0("__NSArray0");
830   static const ConstString g_NSArray1("__NSSingleObjectArrayI");
831   static const ConstString g_NSArrayMLegacy("__NSArrayM_Legacy");
832   static const ConstString g_NSArrayMImmutable("__NSArrayM_Immutable");
833   static const ConstString g_NSCallStackArray("_NSCallStackArray");
834 
835   if (class_name.IsEmpty())
836     return nullptr;
837 
838   if (class_name == g_NSArrayI) {
839     if (runtime->GetFoundationVersion() >= 1436)
840       return (new Foundation1436::NSArrayISyntheticFrontEnd(valobj_sp));
841     if (runtime->GetFoundationVersion() >= 1430)
842       return (new Foundation1430::NSArrayISyntheticFrontEnd(valobj_sp));
843     else
844       return (new Foundation1300::NSArrayISyntheticFrontEnd(valobj_sp));
845   } else if (class_name == g_NSArrayI_Transfer) {
846       return (new Foundation1436::NSArrayI_TransferSyntheticFrontEnd(valobj_sp));
847   } else if (class_name == g_NSArray0) {
848   } else if (class_name == g_NSFrozenArrayM) {
849     return (new Foundation1436::NSFrozenArrayMSyntheticFrontEnd(valobj_sp));
850   } else if (class_name == g_NSArray0) {
851     return (new NSArray0SyntheticFrontEnd(valobj_sp));
852   } else if (class_name == g_NSArray1) {
853     return (new NSArray1SyntheticFrontEnd(valobj_sp));
854   } else if (class_name == g_NSArrayM) {
855     if (runtime->GetFoundationVersion() >= 1437)
856       return (new Foundation1437::NSArrayMSyntheticFrontEnd(valobj_sp));
857     if (runtime->GetFoundationVersion() >= 1428)
858       return (new Foundation1428::NSArrayMSyntheticFrontEnd(valobj_sp));
859     if (runtime->GetFoundationVersion() >= 1100)
860       return (new Foundation1010::NSArrayMSyntheticFrontEnd(valobj_sp));
861     else
862       return (new Foundation109::NSArrayMSyntheticFrontEnd(valobj_sp));
863   } else if (class_name == g_NSCallStackArray) {
864     return (new CallStackArray::NSCallStackArraySyntheticFrontEnd(valobj_sp));
865   } else {
866     auto &map(NSArray_Additionals::GetAdditionalSynthetics());
867     auto iter = map.find(class_name), end = map.end();
868     if (iter != end)
869       return iter->second(synth, valobj_sp);
870   }
871 
872   return nullptr;
873 }
874