source/Plugins/Language/ObjC/ObjCLanguage.cpp

   1 //===-- ObjCLanguage.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 #include <mutex>
  13
  14 // Other libraries and framework includes
  15 // Project includes
  16 #include "ObjCLanguage.h"
  17
  18 #include "lldb/Core/ConstString.h"
  19 #include "lldb/Core/PluginManager.h"
  20 #include "lldb/Core/StreamString.h"
  21 #include "lldb/Core/ValueObject.h"
  22 #include "lldb/DataFormatters/DataVisualization.h"
  23 #include "lldb/DataFormatters/FormattersHelpers.h"
  24 #include "lldb/Symbol/CompilerType.h"
  25 #include "lldb/Target/Target.h"
  26 #include "lldb/Target/ObjCLanguageRuntime.h"
  27 #include "lldb/Symbol/ClangASTContext.h"
  28
  29 #include "CF.h"
  30 #include "Cocoa.h"
  31 #include "CoreMedia.h"
  32 #include "NSDictionary.h"
  33 #include "NSSet.h"
  34 #include "NSString.h"
  35
  36 using namespace lldb;
  37 using namespace lldb_private;
  38 using namespace lldb_private::formatters;
  39
  40 void
  41 ObjCLanguage::Initialize()
  42 {
  43     PluginManager::RegisterPlugin (GetPluginNameStatic(),
  44                                    "Objective-C Language",
  45                                    CreateInstance);
  46 }
  47
  48 void
  49 ObjCLanguage::Terminate()
  50 {
  51     PluginManager::UnregisterPlugin (CreateInstance);
  52 }
  53
  54 lldb_private::ConstString
  55 ObjCLanguage::GetPluginNameStatic()
  56 {
  57     static ConstString g_name("objc");
  58     return g_name;
  59 }
  60
  61 //------------------------------------------------------------------
  62 // PluginInterface protocol
  63 //------------------------------------------------------------------
  64
  65 lldb_private::ConstString
  66 ObjCLanguage::GetPluginName()
  67 {
  68     return GetPluginNameStatic();
  69 }
  70
  71 uint32_t
  72 ObjCLanguage::GetPluginVersion()
  73 {
  74     return 1;
  75 }
  76
  77 //------------------------------------------------------------------
  78 // Static Functions
  79 //------------------------------------------------------------------
  80
  81 Language *
  82 ObjCLanguage::CreateInstance (lldb::LanguageType language)
  83 {
  84     switch (language)
  85     {
  86         case lldb::eLanguageTypeObjC:
  87             return new ObjCLanguage();
  88         default:
  89             return nullptr;
  90     }
  91 }
  92
  93 void
  94 ObjCLanguage::MethodName::Clear()
  95 {
  96     m_full.Clear();
  97     m_class.Clear();
  98     m_category.Clear();
  99     m_selector.Clear();
 100     m_type = eTypeUnspecified;
 101     m_category_is_valid = false;
 102 }
 103
 104 bool
 105 ObjCLanguage::MethodName::SetName (const char *name, bool strict)
 106 {
 107     Clear();
 108     if (name && name[0])
 109     {
 110         // If "strict" is true. then the method must be specified with a
 111         // '+' or '-' at the beginning. If "strict" is false, then the '+'
 112         // or '-' can be omitted
 113         bool valid_prefix = false;
 114
 115         if (name[0] == '+' || name[0] == '-')
 116         {
 117             valid_prefix = name[1] == '[';
 118             if (name[0] == '+')
 119                 m_type = eTypeClassMethod;
 120             else
 121                 m_type = eTypeInstanceMethod;
 122         }
 123         else if (!strict)
 124         {
 125             // "strict" is false, the name just needs to start with '['
 126             valid_prefix = name[0] == '[';
 127         }
 128
 129         if (valid_prefix)
 130         {
 131             int name_len = strlen (name);
 132             // Objective C methods must have at least:
 133             //      "-[" or "+[" prefix
 134             //      One character for a class name
 135             //      One character for the space between the class name
 136             //      One character for the method name
 137             //      "]" suffix
 138             if (name_len >= (5 + (strict ? 1 : 0)) && name[name_len - 1] == ']')
 139             {
 140                 m_full.SetCStringWithLength(name, name_len);
 141             }
 142         }
 143     }
 144     return IsValid(strict);
 145 }
 146
 147 const ConstString &
 148 ObjCLanguage::MethodName::GetClassName ()
 149 {
 150     if (!m_class)
 151     {
 152         if (IsValid(false))
 153         {
 154             const char *full = m_full.GetCString();
 155             const char *class_start = (full[0] == '[' ? full + 1 : full + 2);
 156             const char *paren_pos = strchr (class_start, '(');
 157             if (paren_pos)
 158             {
 159                 m_class.SetCStringWithLength (class_start, paren_pos - class_start);
 160             }
 161             else
 162             {
 163                 // No '(' was found in the full name, we can definitively say
 164                 // that our category was valid (and empty).
 165                 m_category_is_valid = true;
 166                 const char *space_pos = strchr (full, ' ');
 167                 if (space_pos)
 168                 {
 169                     m_class.SetCStringWithLength (class_start, space_pos - class_start);
 170                     if (!m_class_category)
 171                     {
 172                         // No category in name, so we can also fill in the m_class_category
 173                         m_class_category = m_class;
 174                     }
 175                 }
 176             }
 177         }
 178     }
 179     return m_class;
 180 }
 181
 182 const ConstString &
 183 ObjCLanguage::MethodName::GetClassNameWithCategory ()
 184 {
 185     if (!m_class_category)
 186     {
 187         if (IsValid(false))
 188         {
 189             const char *full = m_full.GetCString();
 190             const char *class_start = (full[0] == '[' ? full + 1 : full + 2);
 191             const char *space_pos = strchr (full, ' ');
 192             if (space_pos)
 193             {
 194                 m_class_category.SetCStringWithLength (class_start, space_pos - class_start);
 195                 // If m_class hasn't been filled in and the class with category doesn't
 196                 // contain a '(', then we can also fill in the m_class
 197                 if (!m_class && strchr(m_class_category.GetCString(), '(') == nullptr)
 198                 {
 199                     m_class = m_class_category;
 200                     // No '(' was found in the full name, we can definitively say
 201                     // that our category was valid (and empty).
 202                     m_category_is_valid = true;
 203
 204                 }
 205             }
 206         }
 207     }
 208     return m_class_category;
 209 }
 210
 211 const ConstString &
 212 ObjCLanguage::MethodName::GetSelector ()
 213 {
 214     if (!m_selector)
 215     {
 216         if (IsValid(false))
 217         {
 218             const char *full = m_full.GetCString();
 219             const char *space_pos = strchr (full, ' ');
 220             if (space_pos)
 221             {
 222                 ++space_pos; // skip the space
 223                 m_selector.SetCStringWithLength (space_pos, m_full.GetLength() - (space_pos - full) - 1);
 224             }
 225         }
 226     }
 227     return m_selector;
 228 }
 229
 230 const ConstString &
 231 ObjCLanguage::MethodName::GetCategory ()
 232 {
 233     if (!m_category_is_valid && !m_category)
 234     {
 235         if (IsValid(false))
 236         {
 237             m_category_is_valid = true;
 238             const char *full = m_full.GetCString();
 239             const char *class_start = (full[0] == '[' ? full + 1 : full + 2);
 240             const char *open_paren_pos = strchr (class_start, '(');
 241             if (open_paren_pos)
 242             {
 243                 ++open_paren_pos; // Skip the open paren
 244                 const char *close_paren_pos = strchr (open_paren_pos, ')');
 245                 if (close_paren_pos)
 246                     m_category.SetCStringWithLength (open_paren_pos, close_paren_pos - open_paren_pos);
 247             }
 248         }
 249     }
 250     return m_category;
 251 }
 252
 253 ConstString
 254 ObjCLanguage::MethodName::GetFullNameWithoutCategory (bool empty_if_no_category)
 255 {
 256     if (IsValid(false))
 257     {
 258         if (HasCategory())
 259         {
 260             StreamString strm;
 261             if (m_type == eTypeClassMethod)
 262                 strm.PutChar('+');
 263             else if (m_type == eTypeInstanceMethod)
 264                 strm.PutChar('-');
 265             strm.Printf("[%s %s]", GetClassName().GetCString(), GetSelector().GetCString());
 266             return ConstString(strm.GetString().c_str());
 267         }
 268
 269         if (!empty_if_no_category)
 270         {
 271             // Just return the full name since it doesn't have a category
 272             return GetFullName();
 273         }
 274     }
 275     return ConstString();
 276 }
 277
 278 size_t
 279 ObjCLanguage::MethodName::GetFullNames (std::vector<ConstString> &names, bool append)
 280 {
 281     if (!append)
 282         names.clear();
 283     if (IsValid(false))
 284     {
 285         StreamString strm;
 286         const bool is_class_method = m_type == eTypeClassMethod;
 287         const bool is_instance_method = m_type == eTypeInstanceMethod;
 288         const ConstString &category = GetCategory();
 289         if (is_class_method || is_instance_method)
 290         {
 291             names.push_back (m_full);
 292             if (category)
 293             {
 294                 strm.Printf("%c[%s %s]",
 295                             is_class_method ? '+' : '-',
 296                             GetClassName().GetCString(),
 297                             GetSelector().GetCString());
 298                 names.push_back(ConstString(strm.GetString().c_str()));
 299             }
 300         }
 301         else
 302         {
 303             const ConstString &class_name = GetClassName();
 304             const ConstString &selector = GetSelector();
 305             strm.Printf("+[%s %s]", class_name.GetCString(), selector.GetCString());
 306             names.push_back(ConstString(strm.GetString().c_str()));
 307             strm.Clear();
 308             strm.Printf("-[%s %s]", class_name.GetCString(), selector.GetCString());
 309             names.push_back(ConstString(strm.GetString().c_str()));
 310             strm.Clear();
 311             if (category)
 312             {
 313                 strm.Printf("+[%s(%s) %s]", class_name.GetCString(), category.GetCString(), selector.GetCString());
 314                 names.push_back(ConstString(strm.GetString().c_str()));
 315                 strm.Clear();
 316                 strm.Printf("-[%s(%s) %s]", class_name.GetCString(), category.GetCString(), selector.GetCString());
 317                 names.push_back(ConstString(strm.GetString().c_str()));
 318             }
 319         }
 320     }
 321     return names.size();
 322 }
 323
 324 static void
 325 LoadObjCFormatters(TypeCategoryImplSP objc_category_sp)
 326 {
 327     if (!objc_category_sp)
 328         return;
 329
 330     TypeSummaryImpl::Flags objc_flags;
 331     objc_flags.SetCascades(false)
 332     .SetSkipPointers(true)
 333     .SetSkipReferences(true)
 334     .SetDontShowChildren(true)
 335     .SetDontShowValue(true)
 336     .SetShowMembersOneLiner(false)
 337     .SetHideItemNames(false);
 338
 339     lldb::TypeSummaryImplSP ObjC_BOOL_summary(new CXXFunctionSummaryFormat(objc_flags, lldb_private::formatters::ObjCBOOLSummaryProvider,""));
 340     objc_category_sp->GetTypeSummariesContainer()->Add(ConstString("BOOL"),
 341                                                        ObjC_BOOL_summary);
 342     objc_category_sp->GetTypeSummariesContainer()->Add(ConstString("BOOL &"),
 343                                                        ObjC_BOOL_summary);
 344     objc_category_sp->GetTypeSummariesContainer()->Add(ConstString("BOOL *"),
 345                                                        ObjC_BOOL_summary);
 346
 347 #ifndef LLDB_DISABLE_PYTHON
 348     // we need to skip pointers here since we are special casing a SEL* when retrieving its value
 349     objc_flags.SetSkipPointers(true);
 350     AddCXXSummary(objc_category_sp, lldb_private::formatters::ObjCSELSummaryProvider<false>, "SEL summary provider", ConstString("SEL"), objc_flags);
 351     AddCXXSummary(objc_category_sp, lldb_private::formatters::ObjCSELSummaryProvider<false>, "SEL summary provider", ConstString("struct objc_selector"), objc_flags);
 352     AddCXXSummary(objc_category_sp, lldb_private::formatters::ObjCSELSummaryProvider<false>, "SEL summary provider", ConstString("objc_selector"), objc_flags);
 353     AddCXXSummary(objc_category_sp, lldb_private::formatters::ObjCSELSummaryProvider<true>, "SEL summary provider", ConstString("objc_selector *"), objc_flags);
 354     AddCXXSummary(objc_category_sp, lldb_private::formatters::ObjCSELSummaryProvider<true>, "SEL summary provider", ConstString("SEL *"), objc_flags);
 355
 356     AddCXXSummary(objc_category_sp, lldb_private::formatters::ObjCClassSummaryProvider, "Class summary provider", ConstString("Class"), objc_flags);
 357
 358     SyntheticChildren::Flags class_synth_flags;
 359     class_synth_flags.SetCascades(true).SetSkipPointers(false).SetSkipReferences(false);
 360
 361     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::ObjCClassSyntheticFrontEndCreator, "Class synthetic children", ConstString("Class"), class_synth_flags);
 362 #endif // LLDB_DISABLE_PYTHON
 363
 364     objc_flags.SetSkipPointers(false);
 365     objc_flags.SetCascades(true);
 366     objc_flags.SetSkipReferences(false);
 367
 368     AddStringSummary (objc_category_sp,
 369                       "${var.__FuncPtr%A}",
 370                       ConstString("__block_literal_generic"),
 371                       objc_flags);
 372
 373     AddStringSummary(objc_category_sp,
 374                      "${var.years} years, ${var.months} months, ${var.days} days, ${var.hours} hours, ${var.minutes} minutes ${var.seconds} seconds",
 375                      ConstString("CFGregorianUnits"),
 376                      objc_flags);
 377     AddStringSummary(objc_category_sp,
 378                      "location=${var.location} length=${var.length}",
 379                      ConstString("CFRange"),
 380                      objc_flags);
 381
 382     AddStringSummary(objc_category_sp,
 383                      "location=${var.location}, length=${var.length}",
 384                      ConstString("NSRange"),
 385                      objc_flags);
 386     AddStringSummary(objc_category_sp,
 387                      "(${var.origin}, ${var.size}), ...",
 388                      ConstString("NSRectArray"),
 389                      objc_flags);
 390
 391     AddOneLineSummary (objc_category_sp,
 392                        ConstString("NSPoint"),
 393                        objc_flags);
 394     AddOneLineSummary (objc_category_sp,
 395                        ConstString("NSSize"),
 396                        objc_flags);
 397     AddOneLineSummary (objc_category_sp,
 398                        ConstString("NSRect"),
 399                        objc_flags);
 400
 401     AddOneLineSummary (objc_category_sp,
 402                        ConstString("CGSize"),
 403                        objc_flags);
 404     AddOneLineSummary (objc_category_sp,
 405                        ConstString("CGPoint"),
 406                        objc_flags);
 407     AddOneLineSummary (objc_category_sp,
 408                        ConstString("CGRect"),
 409                        objc_flags);
 410
 411     AddStringSummary(objc_category_sp,
 412                      "red=${var.red} green=${var.green} blue=${var.blue}",
 413                      ConstString("RGBColor"),
 414                      objc_flags);
 415     AddStringSummary(objc_category_sp,
 416                      "(t=${var.top}, l=${var.left}, b=${var.bottom}, r=${var.right})",
 417                      ConstString("Rect"),
 418                      objc_flags);
 419     AddStringSummary(objc_category_sp,
 420                      "{(v=${var.v}, h=${var.h})}",
 421                      ConstString("Point"),
 422                      objc_flags);
 423     AddStringSummary(objc_category_sp,
 424                      "${var.month}/${var.day}/${var.year}  ${var.hour} :${var.minute} :${var.second} dayOfWeek:${var.dayOfWeek}",
 425                      ConstString("DateTimeRect *"),
 426                      objc_flags);
 427     AddStringSummary(objc_category_sp,
 428                      "${var.ld.month}/${var.ld.day}/${var.ld.year} ${var.ld.hour} :${var.ld.minute} :${var.ld.second} dayOfWeek:${var.ld.dayOfWeek}",
 429                      ConstString("LongDateRect"),
 430                      objc_flags);
 431     AddStringSummary(objc_category_sp,
 432                      "(x=${var.x}, y=${var.y})",
 433                      ConstString("HIPoint"),
 434                      objc_flags);
 435     AddStringSummary(objc_category_sp,
 436                      "origin=${var.origin} size=${var.size}",
 437                      ConstString("HIRect"),
 438                      objc_flags);
 439
 440     TypeSummaryImpl::Flags appkit_flags;
 441     appkit_flags.SetCascades(true)
 442     .SetSkipPointers(false)
 443     .SetSkipReferences(false)
 444     .SetDontShowChildren(true)
 445     .SetDontShowValue(false)
 446     .SetShowMembersOneLiner(false)
 447     .SetHideItemNames(false);
 448
 449     appkit_flags.SetDontShowChildren(false);
 450
 451 #ifndef LLDB_DISABLE_PYTHON
 452     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSArraySummaryProvider, "NSArray summary provider", ConstString("NSArray"), appkit_flags);
 453     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSArraySummaryProvider, "NSArray summary provider", ConstString("NSMutableArray"), appkit_flags);
 454     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSArraySummaryProvider, "NSArray summary provider", ConstString("__NSArrayI"), appkit_flags);
 455     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSArraySummaryProvider, "NSArray summary provider", ConstString("__NSArray0"), appkit_flags);
 456     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSArraySummaryProvider, "NSArray summary provider", ConstString("__NSSingleObjectArrayI"), appkit_flags);
 457     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSArraySummaryProvider, "NSArray summary provider", ConstString("__NSArrayM"), appkit_flags);
 458     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSArraySummaryProvider, "NSArray summary provider", ConstString("__NSCFArray"), appkit_flags);
 459     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSArraySummaryProvider, "NSArray summary provider", ConstString("CFArrayRef"), appkit_flags);
 460     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSArraySummaryProvider, "NSArray summary provider", ConstString("CFMutableArrayRef"), appkit_flags);
 461
 462     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDictionarySummaryProvider<false>, "NSDictionary summary provider", ConstString("NSDictionary"), appkit_flags);
 463     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDictionarySummaryProvider<false>, "NSDictionary summary provider", ConstString("NSMutableDictionary"), appkit_flags);
 464     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDictionarySummaryProvider<false>, "NSDictionary summary provider", ConstString("__NSCFDictionary"), appkit_flags);
 465     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDictionarySummaryProvider<false>, "NSDictionary summary provider", ConstString("__NSDictionaryI"), appkit_flags);
 466     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDictionarySummaryProvider<false>, "NSDictionary summary provider", ConstString("__NSSingleEntryDictionaryI"), appkit_flags);
 467     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDictionarySummaryProvider<false>, "NSDictionary summary provider", ConstString("__NSDictionaryM"), appkit_flags);
 468     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDictionarySummaryProvider<true>, "NSDictionary summary provider", ConstString("CFDictionaryRef"), appkit_flags);
 469     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDictionarySummaryProvider<true>, "NSDictionary summary provider", ConstString("CFMutableDictionaryRef"), appkit_flags);
 470
 471     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSSetSummaryProvider<false>, "NSSet summary", ConstString("NSSet"), appkit_flags);
 472     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSSetSummaryProvider<false>, "NSMutableSet summary", ConstString("NSMutableSet"), appkit_flags);
 473     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSSetSummaryProvider<true>, "CFSetRef summary", ConstString("CFSetRef"), appkit_flags);
 474     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSSetSummaryProvider<true>, "CFMutableSetRef summary", ConstString("CFMutableSetRef"), appkit_flags);
 475     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSSetSummaryProvider<false>, "__NSCFSet summary", ConstString("__NSCFSet"), appkit_flags);
 476     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSSetSummaryProvider<false>, "__NSSetI summary", ConstString("__NSSetI"), appkit_flags);
 477     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSSetSummaryProvider<false>, "__NSSetM summary", ConstString("__NSSetM"), appkit_flags);
 478     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSSetSummaryProvider<false>, "NSCountedSet summary", ConstString("NSCountedSet"), appkit_flags);
 479     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSSetSummaryProvider<false>, "NSMutableSet summary", ConstString("NSMutableSet"), appkit_flags);
 480     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSSetSummaryProvider<false>, "NSOrderedSet summary", ConstString("NSOrderedSet"), appkit_flags);
 481     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSSetSummaryProvider<false>, "__NSOrderedSetI summary", ConstString("__NSOrderedSetI"), appkit_flags);
 482     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSSetSummaryProvider<false>, "__NSOrderedSetM summary", ConstString("__NSOrderedSetM"), appkit_flags);
 483
 484     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSError_SummaryProvider, "NSError summary provider", ConstString("NSError"), appkit_flags);
 485     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSException_SummaryProvider, "NSException summary provider", ConstString("NSException"), appkit_flags);
 486
 487     // AddSummary(appkit_category_sp, "${var.key%@} -> ${var.value%@}", ConstString("$_lldb_typegen_nspair"), appkit_flags);
 488
 489     appkit_flags.SetDontShowChildren(true);
 490
 491     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSArraySyntheticFrontEndCreator, "NSArray synthetic children", ConstString("__NSArrayM"), ScriptedSyntheticChildren::Flags());
 492     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSArraySyntheticFrontEndCreator, "NSArray synthetic children", ConstString("__NSArrayI"), ScriptedSyntheticChildren::Flags());
 493     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSArraySyntheticFrontEndCreator, "NSArray synthetic children", ConstString("__NSArray0"), ScriptedSyntheticChildren::Flags());
 494     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSArraySyntheticFrontEndCreator, "NSArray synthetic children", ConstString("__NSSingleObjectArrayI"), ScriptedSyntheticChildren::Flags());
 495     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSArraySyntheticFrontEndCreator, "NSArray synthetic children", ConstString("NSArray"), ScriptedSyntheticChildren::Flags());
 496     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSArraySyntheticFrontEndCreator, "NSArray synthetic children", ConstString("NSMutableArray"), ScriptedSyntheticChildren::Flags());
 497     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSArraySyntheticFrontEndCreator, "NSArray synthetic children", ConstString("__NSCFArray"), ScriptedSyntheticChildren::Flags());
 498     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSArraySyntheticFrontEndCreator, "NSArray synthetic children", ConstString("CFMutableArrayRef"), ScriptedSyntheticChildren::Flags());
 499     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSArraySyntheticFrontEndCreator, "NSArray synthetic children", ConstString("CFArrayRef"), ScriptedSyntheticChildren::Flags());
 500
 501     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSDictionarySyntheticFrontEndCreator, "NSDictionary synthetic children", ConstString("__NSDictionaryM"), ScriptedSyntheticChildren::Flags());
 502     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSDictionarySyntheticFrontEndCreator, "NSDictionary synthetic children", ConstString("__NSDictionaryI"), ScriptedSyntheticChildren::Flags());
 503     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSDictionarySyntheticFrontEndCreator, "NSDictionary synthetic children", ConstString("__NSSingleEntryDictionaryI"), ScriptedSyntheticChildren::Flags());
 504     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSDictionarySyntheticFrontEndCreator, "NSDictionary synthetic children", ConstString("__NSCFDictionary"), ScriptedSyntheticChildren::Flags());
 505     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSDictionarySyntheticFrontEndCreator, "NSDictionary synthetic children", ConstString("NSDictionary"), ScriptedSyntheticChildren::Flags());
 506     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSDictionarySyntheticFrontEndCreator, "NSDictionary synthetic children", ConstString("NSMutableDictionary"), ScriptedSyntheticChildren::Flags());
 507     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSDictionarySyntheticFrontEndCreator, "NSDictionary synthetic children", ConstString("CFDictionaryRef"), ScriptedSyntheticChildren::Flags());
 508     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSDictionarySyntheticFrontEndCreator, "NSDictionary synthetic children", ConstString("CFMutableDictionaryRef"), ScriptedSyntheticChildren::Flags());
 509
 510     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSErrorSyntheticFrontEndCreator, "NSError synthetic children", ConstString("NSError"), ScriptedSyntheticChildren::Flags());
 511     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSExceptionSyntheticFrontEndCreator, "NSException synthetic children", ConstString("NSException"), ScriptedSyntheticChildren::Flags());
 512
 513     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSSetSyntheticFrontEndCreator, "NSSet synthetic children", ConstString("NSSet"), ScriptedSyntheticChildren::Flags());
 514     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSSetSyntheticFrontEndCreator, "__NSSetI synthetic children", ConstString("__NSSetI"), ScriptedSyntheticChildren::Flags());
 515     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSSetSyntheticFrontEndCreator, "__NSSetM synthetic children", ConstString("__NSSetM"), ScriptedSyntheticChildren::Flags());
 516     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSSetSyntheticFrontEndCreator, "NSMutableSet synthetic children", ConstString("NSMutableSet"), ScriptedSyntheticChildren::Flags());
 517     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSSetSyntheticFrontEndCreator, "NSOrderedSet synthetic children", ConstString("NSOrderedSet"), ScriptedSyntheticChildren::Flags());
 518     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSSetSyntheticFrontEndCreator, "__NSOrderedSetI synthetic children", ConstString("__NSOrderedSetI"), ScriptedSyntheticChildren::Flags());
 519     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSSetSyntheticFrontEndCreator, "__NSOrderedSetM synthetic children", ConstString("__NSOrderedSetM"), ScriptedSyntheticChildren::Flags());
 520
 521     AddCXXSynthetic(objc_category_sp, lldb_private::formatters::NSIndexPathSyntheticFrontEndCreator, "NSIndexPath synthetic children", ConstString("NSIndexPath"), ScriptedSyntheticChildren::Flags());
 522
 523     AddCXXSummary(objc_category_sp,lldb_private::formatters::CFBagSummaryProvider, "CFBag summary provider", ConstString("CFBagRef"), appkit_flags);
 524     AddCXXSummary(objc_category_sp,lldb_private::formatters::CFBagSummaryProvider, "CFBag summary provider", ConstString("__CFBag"), appkit_flags);
 525     AddCXXSummary(objc_category_sp,lldb_private::formatters::CFBagSummaryProvider, "CFBag summary provider", ConstString("const struct __CFBag"), appkit_flags);
 526     AddCXXSummary(objc_category_sp,lldb_private::formatters::CFBagSummaryProvider, "CFBag summary provider", ConstString("CFMutableBagRef"), appkit_flags);
 527
 528     AddCXXSummary(objc_category_sp,lldb_private::formatters::CFBinaryHeapSummaryProvider, "CFBinaryHeap summary provider", ConstString("CFBinaryHeapRef"), appkit_flags);
 529     AddCXXSummary(objc_category_sp,lldb_private::formatters::CFBinaryHeapSummaryProvider, "CFBinaryHeap summary provider", ConstString("__CFBinaryHeap"), appkit_flags);
 530
 531     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSStringSummaryProvider, "NSString summary provider", ConstString("NSString"), appkit_flags);
 532     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSStringSummaryProvider, "NSString summary provider", ConstString("CFStringRef"), appkit_flags);
 533     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSStringSummaryProvider, "NSString summary provider", ConstString("__CFString"), appkit_flags);
 534     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSStringSummaryProvider, "NSString summary provider", ConstString("CFMutableStringRef"), appkit_flags);
 535     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSStringSummaryProvider, "NSString summary provider", ConstString("NSMutableString"), appkit_flags);
 536     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSStringSummaryProvider, "NSString summary provider", ConstString("__NSCFConstantString"), appkit_flags);
 537     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSStringSummaryProvider, "NSString summary provider", ConstString("__NSCFString"), appkit_flags);
 538     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSStringSummaryProvider, "NSString summary provider", ConstString("NSCFConstantString"), appkit_flags);
 539     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSStringSummaryProvider, "NSString summary provider", ConstString("NSCFString"), appkit_flags);
 540     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSStringSummaryProvider, "NSString summary provider", ConstString("NSPathStore2"), appkit_flags);
 541     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSStringSummaryProvider, "NSString summary provider", ConstString("NSTaggedPointerString"), appkit_flags);
 542
 543     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSAttributedStringSummaryProvider, "NSAttributedString summary provider", ConstString("NSAttributedString"), appkit_flags);
 544     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSMutableAttributedStringSummaryProvider, "NSMutableAttributedString summary provider", ConstString("NSMutableAttributedString"), appkit_flags);
 545     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSMutableAttributedStringSummaryProvider, "NSMutableAttributedString summary provider", ConstString("NSConcreteMutableAttributedString"), appkit_flags);
 546
 547     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSBundleSummaryProvider, "NSBundle summary provider", ConstString("NSBundle"), appkit_flags);
 548
 549     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDataSummaryProvider<false>, "NSData summary provider", ConstString("NSData"), appkit_flags);
 550     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDataSummaryProvider<false>, "NSData summary provider", ConstString("_NSInlineData"), appkit_flags);
 551     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDataSummaryProvider<false>, "NSData summary provider", ConstString("NSConcreteData"), appkit_flags);
 552     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDataSummaryProvider<false>, "NSData summary provider", ConstString("NSConcreteMutableData"), appkit_flags);
 553     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDataSummaryProvider<false>, "NSData summary provider", ConstString("NSMutableData"), appkit_flags);
 554     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDataSummaryProvider<false>, "NSData summary provider", ConstString("__NSCFData"), appkit_flags);
 555     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDataSummaryProvider<true>, "NSData summary provider", ConstString("CFDataRef"), appkit_flags);
 556     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDataSummaryProvider<true>, "NSData summary provider", ConstString("CFMutableDataRef"), appkit_flags);
 557
 558     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSMachPortSummaryProvider, "NSMachPort summary provider", ConstString("NSMachPort"), appkit_flags);
 559
 560     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSNotificationSummaryProvider, "NSNotification summary provider", ConstString("NSNotification"), appkit_flags);
 561     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSNotificationSummaryProvider, "NSNotification summary provider", ConstString("NSConcreteNotification"), appkit_flags);
 562
 563     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSNumberSummaryProvider, "NSNumber summary provider", ConstString("NSNumber"), appkit_flags);
 564     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSNumberSummaryProvider, "CFNumberRef summary provider", ConstString("CFNumberRef"), appkit_flags);
 565     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSNumberSummaryProvider, "NSNumber summary provider", ConstString("__NSCFBoolean"), appkit_flags);
 566     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSNumberSummaryProvider, "NSNumber summary provider", ConstString("__NSCFNumber"), appkit_flags);
 567     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSNumberSummaryProvider, "NSNumber summary provider", ConstString("NSCFBoolean"), appkit_flags);
 568     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSNumberSummaryProvider, "NSNumber summary provider", ConstString("NSCFNumber"), appkit_flags);
 569
 570     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSURLSummaryProvider, "NSURL summary provider", ConstString("NSURL"), appkit_flags);
 571     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSURLSummaryProvider, "NSURL summary provider", ConstString("CFURLRef"), appkit_flags);
 572
 573     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDateSummaryProvider, "NSDate summary provider", ConstString("NSDate"), appkit_flags);
 574     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDateSummaryProvider, "NSDate summary provider", ConstString("__NSDate"), appkit_flags);
 575     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDateSummaryProvider, "NSDate summary provider", ConstString("__NSTaggedDate"), appkit_flags);
 576     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSDateSummaryProvider, "NSDate summary provider", ConstString("NSCalendarDate"), appkit_flags);
 577
 578     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSTimeZoneSummaryProvider, "NSTimeZone summary provider", ConstString("NSTimeZone"), appkit_flags);
 579     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSTimeZoneSummaryProvider, "NSTimeZone summary provider", ConstString("CFTimeZoneRef"), appkit_flags);
 580     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSTimeZoneSummaryProvider, "NSTimeZone summary provider", ConstString("__NSTimeZone"), appkit_flags);
 581
 582     // CFAbsoluteTime is actually a double rather than a pointer to an object
 583     // we do not care about the numeric value, since it is probably meaningless to users
 584     appkit_flags.SetDontShowValue(true);
 585     AddCXXSummary(objc_category_sp, lldb_private::formatters::CFAbsoluteTimeSummaryProvider, "CFAbsoluteTime summary provider", ConstString("CFAbsoluteTime"), appkit_flags);
 586     appkit_flags.SetDontShowValue(false);
 587
 588     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSIndexSetSummaryProvider, "NSIndexSet summary provider", ConstString("NSIndexSet"), appkit_flags);
 589     AddCXXSummary(objc_category_sp, lldb_private::formatters::NSIndexSetSummaryProvider, "NSIndexSet summary provider", ConstString("NSMutableIndexSet"), appkit_flags);
 590
 591     AddStringSummary(objc_category_sp,
 592                      "@\"${var.month%d}/${var.day%d}/${var.year%d} ${var.hour%d}:${var.minute%d}:${var.second}\"",
 593                      ConstString("CFGregorianDate"),
 594                      appkit_flags);
 595
 596     AddCXXSummary(objc_category_sp, lldb_private::formatters::CFBitVectorSummaryProvider, "CFBitVector summary provider", ConstString("CFBitVectorRef"), appkit_flags);
 597     AddCXXSummary(objc_category_sp, lldb_private::formatters::CFBitVectorSummaryProvider, "CFBitVector summary provider", ConstString("CFMutableBitVectorRef"), appkit_flags);
 598     AddCXXSummary(objc_category_sp, lldb_private::formatters::CFBitVectorSummaryProvider, "CFBitVector summary provider", ConstString("__CFBitVector"), appkit_flags);
 599     AddCXXSummary(objc_category_sp, lldb_private::formatters::CFBitVectorSummaryProvider, "CFBitVector summary provider", ConstString("__CFMutableBitVector"), appkit_flags);
 600 #endif // LLDB_DISABLE_PYTHON
 601 }
 602
 603 static void
 604 LoadCoreMediaFormatters(TypeCategoryImplSP objc_category_sp)
 605 {
 606     if (!objc_category_sp)
 607         return;
 608
 609     TypeSummaryImpl::Flags cm_flags;
 610     cm_flags.SetCascades(true)
 611     .SetDontShowChildren(false)
 612     .SetDontShowValue(false)
 613     .SetHideItemNames(false)
 614     .SetShowMembersOneLiner(false)
 615     .SetSkipPointers(false)
 616     .SetSkipReferences(false);
 617
 618 #ifndef LLDB_DISABLE_PYTHON
 619     AddCXXSummary(objc_category_sp, lldb_private::formatters::CMTimeSummaryProvider, "CMTime summary provider", ConstString("CMTime"), cm_flags);
 620 #endif // LLDB_DISABLE_PYTHON
 621 }
 622
 623 lldb::TypeCategoryImplSP
 624 ObjCLanguage::GetFormatters ()
 625 {
 626     static std::once_flag g_initialize;
 627     static TypeCategoryImplSP g_category;
 628
 629     std::call_once(g_initialize, [this] () -> void {
 630         DataVisualization::Categories::GetCategory(GetPluginName(), g_category);
 631         if (g_category)
 632         {
 633             LoadCoreMediaFormatters(g_category);
 634             LoadObjCFormatters(g_category);
 635         }
 636     });
 637     return g_category;
 638 }
 639
 640 std::vector<ConstString>
 641 ObjCLanguage::GetPossibleFormattersMatches (ValueObject& valobj, lldb::DynamicValueType use_dynamic)
 642 {
 643     std::vector<ConstString> result;
 644
 645     if (use_dynamic == lldb::eNoDynamicValues)
 646         return result;
 647
 648     CompilerType compiler_type(valobj.GetCompilerType());
 649
 650     const bool check_cpp = false;
 651     const bool check_objc = true;
 652     bool canBeObjCDynamic = compiler_type.IsPossibleDynamicType(nullptr, check_cpp, check_objc);
 653
 654     if (canBeObjCDynamic)
 655     {
 656         do {
 657             lldb::ProcessSP process_sp = valobj.GetProcessSP();
 658             if (!process_sp)
 659                 break;
 660             ObjCLanguageRuntime* runtime = process_sp->GetObjCLanguageRuntime();
 661             if (runtime == nullptr)
 662                 break;
 663             ObjCLanguageRuntime::ClassDescriptorSP objc_class_sp (runtime->GetClassDescriptor(valobj));
 664             if (!objc_class_sp)
 665                 break;
 666             if (ConstString name = objc_class_sp->GetClassName())
 667                 result.push_back(name);
 668         } while (false);
 669     }
 670
 671     return result;
 672 }
 673
 674 std::unique_ptr<Language::TypeScavenger>
 675 ObjCLanguage::GetTypeScavenger ()
 676 {
 677     class ObjCTypeScavenger : public Language::TypeScavenger
 678     {
 679     private:
 680         class ObjCScavengerResult : public Language::TypeScavenger::Result
 681         {
 682         public:
 683             ObjCScavengerResult (CompilerType type) :
 684                 Language::TypeScavenger::Result(),
 685                 m_compiler_type(type)
 686             {
 687             }
 688
 689             bool
 690             IsValid () override
 691             {
 692                 return m_compiler_type.IsValid();
 693             }
 694
 695             bool
 696             DumpToStream (Stream& stream,
 697                           bool print_help_if_available) override
 698             {
 699                 if (IsValid())
 700                 {
 701                     m_compiler_type.DumpTypeDescription(&stream);
 702                     stream.EOL();
 703                     return true;
 704                 }
 705                 return false;
 706             }
 707
 708             ~ObjCScavengerResult() override = default;
 709
 710         private:
 711             CompilerType m_compiler_type;
 712         };
 713
 714     protected:
 715         ObjCTypeScavenger() = default;
 716
 717         ~ObjCTypeScavenger() override = default;
 718
 719         bool
 720         Find_Impl (ExecutionContextScope *exe_scope,
 721                    const char *key,
 722                    ResultSet &results) override
 723         {
 724             bool result = false;
 725
 726             Target* target = exe_scope->CalculateTarget().get();
 727             if (target)
 728             {
 729                 if (auto clang_modules_decl_vendor = target->GetClangModulesDeclVendor())
 730                 {
 731                     std::vector <clang::NamedDecl*> decls;
 732                     ConstString key_cs(key);
 733
 734                     if (clang_modules_decl_vendor->FindDecls(key_cs, false, UINT32_MAX, decls) > 0 &&
 735                         !decls.empty())
 736                     {
 737                         CompilerType module_type = ClangASTContext::GetTypeForDecl(decls.front());
 738                         result = true;
 739                         std::unique_ptr<Language::TypeScavenger::Result> result(new ObjCScavengerResult(module_type));
 740                         results.insert(std::move(result));
 741                     }
 742                 }
 743             }
 744
 745             if (!result)
 746             {
 747                 Process* process = exe_scope->CalculateProcess().get();
 748                 if (process)
 749                 {
 750                     const bool create_on_demand = false;
 751                     auto objc_runtime = process->GetObjCLanguageRuntime(create_on_demand);
 752                     if (objc_runtime)
 753                     {
 754                         auto decl_vendor = objc_runtime->GetDeclVendor();
 755                         if (decl_vendor)
 756                         {
 757                             std::vector<clang::NamedDecl *> decls;
 758                             ConstString name(key);
 759                             decl_vendor->FindDecls(name, true, UINT32_MAX, decls);
 760                             for (auto decl : decls)
 761                             {
 762                                 if (decl)
 763                                 {
 764                                     if (CompilerType candidate = ClangASTContext::GetTypeForDecl(decl))
 765                                     {
 766                                         result = true;
 767                                         std::unique_ptr<Language::TypeScavenger::Result> result(new ObjCScavengerResult(candidate));
 768                                         results.insert(std::move(result));
 769                                     }
 770                                 }
 771                             }
 772                         }
 773                     }
 774                 }
 775             }
 776
 777             return result;
 778         }
 779
 780         friend class lldb_private::ObjCLanguage;
 781     };
 782
 783     return std::unique_ptr<TypeScavenger>(new ObjCTypeScavenger());
 784 }
 785
 786 bool
 787 ObjCLanguage::GetFormatterPrefixSuffix (ValueObject& valobj, ConstString type_hint,
 788                                         std::string& prefix, std::string& suffix)
 789 {
 790     static ConstString g_CFBag("CFBag");
 791     static ConstString g_CFBinaryHeap("CFBinaryHeap");
 792
 793     static ConstString g_NSNumberChar("NSNumber:char");
 794     static ConstString g_NSNumberShort("NSNumber:short");
 795     static ConstString g_NSNumberInt("NSNumber:int");
 796     static ConstString g_NSNumberLong("NSNumber:long");
 797     static ConstString g_NSNumberFloat("NSNumber:float");
 798     static ConstString g_NSNumberDouble("NSNumber:double");
 799
 800     static ConstString g_NSData("NSData");
 801     static ConstString g_NSArray("NSArray");
 802     static ConstString g_NSString("NSString");
 803     static ConstString g_NSStringStar("NSString*");
 804
 805     if (type_hint.IsEmpty())
 806         return false;
 807
 808     prefix.clear();
 809     suffix.clear();
 810
 811     if (type_hint == g_CFBag ||
 812         type_hint == g_CFBinaryHeap)
 813     {
 814         prefix = "@";
 815         return true;
 816     }
 817
 818     if (type_hint == g_NSNumberChar)
 819     {
 820         prefix = "(char)";
 821         return true;
 822     }
 823     if (type_hint == g_NSNumberShort)
 824     {
 825         prefix = "(short)";
 826         return true;
 827     }
 828     if (type_hint == g_NSNumberInt)
 829     {
 830         prefix = "(int)";
 831         return true;
 832     }
 833     if (type_hint == g_NSNumberLong)
 834     {
 835         prefix = "(long)";
 836         return true;
 837     }
 838     if (type_hint == g_NSNumberFloat)
 839     {
 840         prefix = "(float)";
 841         return true;
 842     }
 843     if (type_hint == g_NSNumberDouble)
 844     {
 845         prefix = "(double)";
 846         return true;
 847     }
 848
 849     if (type_hint == g_NSData ||
 850         type_hint == g_NSArray)
 851     {
 852         prefix = "@\"";
 853         suffix = "\"";
 854         return true;
 855     }
 856
 857     if (type_hint == g_NSString ||
 858         type_hint == g_NSStringStar)
 859     {
 860         prefix = "@";
 861         return true;
 862     }
 863
 864     return false;
 865 }
 866
 867 bool
 868 ObjCLanguage::IsNilReference (ValueObject& valobj)
 869 {
 870     const uint32_t mask = eTypeIsObjC | eTypeIsPointer;
 871     bool isObjCpointer = (((valobj.GetCompilerType().GetTypeInfo(nullptr)) & mask) == mask);
 872     if (!isObjCpointer)
 873         return false;
 874     bool canReadValue = true;
 875     bool isZero = valobj.GetValueAsUnsigned(0,&canReadValue) == 0;
 876     return canReadValue && isZero;
 877 }