contrib/llvm/tools/lldb/source/Plugins/ExpressionParser/Clang/ClangUserExpression.cpp

   1 //===-- ClangUserExpression.cpp ---------------------------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #include <stdio.h>
  11 #if HAVE_SYS_TYPES_H
  12 #include <sys/types.h>
  13 #endif
  14
  15 #include <cstdlib>
  16 #include <map>
  17 #include <string>
  18
  19 #include "ClangUserExpression.h"
  20
  21 #include "ASTResultSynthesizer.h"
  22 #include "ClangDiagnostic.h"
  23 #include "ClangExpressionDeclMap.h"
  24 #include "ClangExpressionParser.h"
  25 #include "ClangModulesDeclVendor.h"
  26 #include "ClangPersistentVariables.h"
  27
  28 #include "lldb/Core/Debugger.h"
  29 #include "lldb/Core/Module.h"
  30 #include "lldb/Core/StreamFile.h"
  31 #include "lldb/Core/ValueObjectConstResult.h"
  32 #include "lldb/Expression/ExpressionSourceCode.h"
  33 #include "lldb/Expression/IRExecutionUnit.h"
  34 #include "lldb/Expression/IRInterpreter.h"
  35 #include "lldb/Expression/Materializer.h"
  36 #include "lldb/Host/HostInfo.h"
  37 #include "lldb/Symbol/Block.h"
  38 #include "lldb/Symbol/ClangASTContext.h"
  39 #include "lldb/Symbol/ClangExternalASTSourceCommon.h"
  40 #include "lldb/Symbol/Function.h"
  41 #include "lldb/Symbol/ObjectFile.h"
  42 #include "lldb/Symbol/SymbolVendor.h"
  43 #include "lldb/Symbol/Type.h"
  44 #include "lldb/Symbol/VariableList.h"
  45 #include "lldb/Target/ExecutionContext.h"
  46 #include "lldb/Target/Process.h"
  47 #include "lldb/Target/StackFrame.h"
  48 #include "lldb/Target/Target.h"
  49 #include "lldb/Target/ThreadPlan.h"
  50 #include "lldb/Target/ThreadPlanCallUserExpression.h"
  51 #include "lldb/Utility/ConstString.h"
  52 #include "lldb/Utility/Log.h"
  53 #include "lldb/Utility/StreamString.h"
  54
  55 #include "clang/AST/DeclCXX.h"
  56 #include "clang/AST/DeclObjC.h"
  57
  58 using namespace lldb_private;
  59
  60 ClangUserExpression::ClangUserExpression(
  61     ExecutionContextScope &exe_scope, llvm::StringRef expr,
  62     llvm::StringRef prefix, lldb::LanguageType language,
  63     ResultType desired_type, const EvaluateExpressionOptions &options)
  64     : LLVMUserExpression(exe_scope, expr, prefix, language, desired_type,
  65                          options),
  66       m_type_system_helper(*m_target_wp.lock().get(),
  67                            options.GetExecutionPolicy() ==
  68                                eExecutionPolicyTopLevel),
  69       m_result_delegate(exe_scope.CalculateTarget()) {
  70   switch (m_language) {
  71   case lldb::eLanguageTypeC_plus_plus:
  72     m_allow_cxx = true;
  73     break;
  74   case lldb::eLanguageTypeObjC:
  75     m_allow_objc = true;
  76     break;
  77   case lldb::eLanguageTypeObjC_plus_plus:
  78   default:
  79     m_allow_cxx = true;
  80     m_allow_objc = true;
  81     break;
  82   }
  83 }
  84
  85 ClangUserExpression::~ClangUserExpression() {}
  86
  87 void ClangUserExpression::ScanContext(ExecutionContext &exe_ctx, Status &err) {
  88   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
  89
  90   if (log)
  91     log->Printf("ClangUserExpression::ScanContext()");
  92
  93   m_target = exe_ctx.GetTargetPtr();
  94
  95   if (!(m_allow_cxx || m_allow_objc)) {
  96     if (log)
  97       log->Printf("  [CUE::SC] Settings inhibit C++ and Objective-C");
  98     return;
  99   }
 100
 101   StackFrame *frame = exe_ctx.GetFramePtr();
 102   if (frame == NULL) {
 103     if (log)
 104       log->Printf("  [CUE::SC] Null stack frame");
 105     return;
 106   }
 107
 108   SymbolContext sym_ctx = frame->GetSymbolContext(lldb::eSymbolContextFunction |
 109                                                   lldb::eSymbolContextBlock);
 110
 111   if (!sym_ctx.function) {
 112     if (log)
 113       log->Printf("  [CUE::SC] Null function");
 114     return;
 115   }
 116
 117   // Find the block that defines the function represented by "sym_ctx"
 118   Block *function_block = sym_ctx.GetFunctionBlock();
 119
 120   if (!function_block) {
 121     if (log)
 122       log->Printf("  [CUE::SC] Null function block");
 123     return;
 124   }
 125
 126   CompilerDeclContext decl_context = function_block->GetDeclContext();
 127
 128   if (!decl_context) {
 129     if (log)
 130       log->Printf("  [CUE::SC] Null decl context");
 131     return;
 132   }
 133
 134   if (clang::CXXMethodDecl *method_decl =
 135           ClangASTContext::DeclContextGetAsCXXMethodDecl(decl_context)) {
 136     if (m_allow_cxx && method_decl->isInstance()) {
 137       if (m_enforce_valid_object) {
 138         lldb::VariableListSP variable_list_sp(
 139             function_block->GetBlockVariableList(true));
 140
 141         const char *thisErrorString = "Stopped in a C++ method, but 'this' "
 142                                       "isn't available; pretending we are in a "
 143                                       "generic context";
 144
 145         if (!variable_list_sp) {
 146           err.SetErrorString(thisErrorString);
 147           return;
 148         }
 149
 150         lldb::VariableSP this_var_sp(
 151             variable_list_sp->FindVariable(ConstString("this")));
 152
 153         if (!this_var_sp || !this_var_sp->IsInScope(frame) ||
 154             !this_var_sp->LocationIsValidForFrame(frame)) {
 155           err.SetErrorString(thisErrorString);
 156           return;
 157         }
 158       }
 159
 160       m_in_cplusplus_method = true;
 161       m_needs_object_ptr = true;
 162     }
 163   } else if (clang::ObjCMethodDecl *method_decl =
 164                  ClangASTContext::DeclContextGetAsObjCMethodDecl(
 165                      decl_context)) {
 166     if (m_allow_objc) {
 167       if (m_enforce_valid_object) {
 168         lldb::VariableListSP variable_list_sp(
 169             function_block->GetBlockVariableList(true));
 170
 171         const char *selfErrorString = "Stopped in an Objective-C method, but "
 172                                       "'self' isn't available; pretending we "
 173                                       "are in a generic context";
 174
 175         if (!variable_list_sp) {
 176           err.SetErrorString(selfErrorString);
 177           return;
 178         }
 179
 180         lldb::VariableSP self_variable_sp =
 181             variable_list_sp->FindVariable(ConstString("self"));
 182
 183         if (!self_variable_sp || !self_variable_sp->IsInScope(frame) ||
 184             !self_variable_sp->LocationIsValidForFrame(frame)) {
 185           err.SetErrorString(selfErrorString);
 186           return;
 187         }
 188       }
 189
 190       m_in_objectivec_method = true;
 191       m_needs_object_ptr = true;
 192
 193       if (!method_decl->isInstanceMethod())
 194         m_in_static_method = true;
 195     }
 196   } else if (clang::FunctionDecl *function_decl =
 197                  ClangASTContext::DeclContextGetAsFunctionDecl(decl_context)) {
 198     // We might also have a function that said in the debug information that it
 199     // captured an object pointer.  The best way to deal with getting to the
 200     // ivars at present is by pretending that this is a method of a class in
 201     // whatever runtime the debug info says the object pointer belongs to.  Do
 202     // that here.
 203
 204     ClangASTMetadata *metadata =
 205         ClangASTContext::DeclContextGetMetaData(decl_context, function_decl);
 206     if (metadata && metadata->HasObjectPtr()) {
 207       lldb::LanguageType language = metadata->GetObjectPtrLanguage();
 208       if (language == lldb::eLanguageTypeC_plus_plus) {
 209         if (m_enforce_valid_object) {
 210           lldb::VariableListSP variable_list_sp(
 211               function_block->GetBlockVariableList(true));
 212
 213           const char *thisErrorString = "Stopped in a context claiming to "
 214                                         "capture a C++ object pointer, but "
 215                                         "'this' isn't available; pretending we "
 216                                         "are in a generic context";
 217
 218           if (!variable_list_sp) {
 219             err.SetErrorString(thisErrorString);
 220             return;
 221           }
 222
 223           lldb::VariableSP this_var_sp(
 224               variable_list_sp->FindVariable(ConstString("this")));
 225
 226           if (!this_var_sp || !this_var_sp->IsInScope(frame) ||
 227               !this_var_sp->LocationIsValidForFrame(frame)) {
 228             err.SetErrorString(thisErrorString);
 229             return;
 230           }
 231         }
 232
 233         m_in_cplusplus_method = true;
 234         m_needs_object_ptr = true;
 235       } else if (language == lldb::eLanguageTypeObjC) {
 236         if (m_enforce_valid_object) {
 237           lldb::VariableListSP variable_list_sp(
 238               function_block->GetBlockVariableList(true));
 239
 240           const char *selfErrorString =
 241               "Stopped in a context claiming to capture an Objective-C object "
 242               "pointer, but 'self' isn't available; pretending we are in a "
 243               "generic context";
 244
 245           if (!variable_list_sp) {
 246             err.SetErrorString(selfErrorString);
 247             return;
 248           }
 249
 250           lldb::VariableSP self_variable_sp =
 251               variable_list_sp->FindVariable(ConstString("self"));
 252
 253           if (!self_variable_sp || !self_variable_sp->IsInScope(frame) ||
 254               !self_variable_sp->LocationIsValidForFrame(frame)) {
 255             err.SetErrorString(selfErrorString);
 256             return;
 257           }
 258
 259           Type *self_type = self_variable_sp->GetType();
 260
 261           if (!self_type) {
 262             err.SetErrorString(selfErrorString);
 263             return;
 264           }
 265
 266           CompilerType self_clang_type = self_type->GetForwardCompilerType();
 267
 268           if (!self_clang_type) {
 269             err.SetErrorString(selfErrorString);
 270             return;
 271           }
 272
 273           if (ClangASTContext::IsObjCClassType(self_clang_type)) {
 274             return;
 275           } else if (ClangASTContext::IsObjCObjectPointerType(
 276                          self_clang_type)) {
 277             m_in_objectivec_method = true;
 278             m_needs_object_ptr = true;
 279           } else {
 280             err.SetErrorString(selfErrorString);
 281             return;
 282           }
 283         } else {
 284           m_in_objectivec_method = true;
 285           m_needs_object_ptr = true;
 286         }
 287       }
 288     }
 289   }
 290 }
 291
 292 // This is a really nasty hack, meant to fix Objective-C expressions of the
 293 // form (int)[myArray count].  Right now, because the type information for
 294 // count is not available, [myArray count] returns id, which can't be directly
 295 // cast to int without causing a clang error.
 296 static void ApplyObjcCastHack(std::string &expr) {
 297 #define OBJC_CAST_HACK_FROM "(int)["
 298 #define OBJC_CAST_HACK_TO "(int)(long long)["
 299
 300   size_t from_offset;
 301
 302   while ((from_offset = expr.find(OBJC_CAST_HACK_FROM)) != expr.npos)
 303     expr.replace(from_offset, sizeof(OBJC_CAST_HACK_FROM) - 1,
 304                  OBJC_CAST_HACK_TO);
 305
 306 #undef OBJC_CAST_HACK_TO
 307 #undef OBJC_CAST_HACK_FROM
 308 }
 309
 310 namespace {
 311 // Utility guard that calls a callback when going out of scope.
 312 class OnExit {
 313 public:
 314   typedef std::function<void(void)> Callback;
 315
 316   OnExit(Callback const &callback) : m_callback(callback) {}
 317
 318   ~OnExit() { m_callback(); }
 319
 320 private:
 321   Callback m_callback;
 322 };
 323 } // namespace
 324
 325 bool ClangUserExpression::SetupPersistentState(DiagnosticManager &diagnostic_manager,
 326                                  ExecutionContext &exe_ctx) {
 327   if (Target *target = exe_ctx.GetTargetPtr()) {
 328     if (PersistentExpressionState *persistent_state =
 329             target->GetPersistentExpressionStateForLanguage(
 330                 lldb::eLanguageTypeC)) {
 331       m_result_delegate.RegisterPersistentState(persistent_state);
 332     } else {
 333       diagnostic_manager.PutString(
 334           eDiagnosticSeverityError,
 335           "couldn't start parsing (no persistent data)");
 336       return false;
 337     }
 338   } else {
 339     diagnostic_manager.PutString(eDiagnosticSeverityError,
 340                                  "error: couldn't start parsing (no target)");
 341     return false;
 342   }
 343   return true;
 344 }
 345
 346 static void SetupDeclVendor(ExecutionContext &exe_ctx, Target *target) {
 347   if (ClangModulesDeclVendor *decl_vendor =
 348           target->GetClangModulesDeclVendor()) {
 349     const ClangModulesDeclVendor::ModuleVector &hand_imported_modules =
 350         llvm::cast<ClangPersistentVariables>(
 351             target->GetPersistentExpressionStateForLanguage(
 352                 lldb::eLanguageTypeC))
 353             ->GetHandLoadedClangModules();
 354     ClangModulesDeclVendor::ModuleVector modules_for_macros;
 355
 356     for (ClangModulesDeclVendor::ModuleID module : hand_imported_modules) {
 357       modules_for_macros.push_back(module);
 358     }
 359
 360     if (target->GetEnableAutoImportClangModules()) {
 361       if (StackFrame *frame = exe_ctx.GetFramePtr()) {
 362         if (Block *block = frame->GetFrameBlock()) {
 363           SymbolContext sc;
 364
 365           block->CalculateSymbolContext(&sc);
 366
 367           if (sc.comp_unit) {
 368             StreamString error_stream;
 369
 370             decl_vendor->AddModulesForCompileUnit(
 371                 *sc.comp_unit, modules_for_macros, error_stream);
 372           }
 373         }
 374       }
 375     }
 376   }
 377 }
 378
 379 llvm::Optional<lldb::LanguageType> ClangUserExpression::GetLanguageForExpr(
 380     DiagnosticManager &diagnostic_manager, ExecutionContext &exe_ctx) {
 381   lldb::LanguageType lang_type = lldb::LanguageType::eLanguageTypeUnknown;
 382
 383   std::string prefix = m_expr_prefix;
 384
 385   if (m_options.GetExecutionPolicy() == eExecutionPolicyTopLevel) {
 386     m_transformed_text = m_expr_text;
 387   } else {
 388     std::unique_ptr<ExpressionSourceCode> source_code(
 389         ExpressionSourceCode::CreateWrapped(prefix.c_str(),
 390                                             m_expr_text.c_str()));
 391
 392     if (m_in_cplusplus_method)
 393       lang_type = lldb::eLanguageTypeC_plus_plus;
 394     else if (m_in_objectivec_method)
 395       lang_type = lldb::eLanguageTypeObjC;
 396     else
 397       lang_type = lldb::eLanguageTypeC;
 398
 399     if (!source_code->GetText(m_transformed_text, lang_type, m_in_static_method,
 400                               exe_ctx)) {
 401       diagnostic_manager.PutString(eDiagnosticSeverityError,
 402                                    "couldn't construct expression body");
 403       return llvm::Optional<lldb::LanguageType>();
 404     }
 405   }
 406   return lang_type;
 407 }
 408
 409 bool ClangUserExpression::PrepareForParsing(
 410     DiagnosticManager &diagnostic_manager, ExecutionContext &exe_ctx) {
 411   InstallContext(exe_ctx);
 412
 413   if (!SetupPersistentState(diagnostic_manager, exe_ctx))
 414     return false;
 415
 416   Status err;
 417   ScanContext(exe_ctx, err);
 418
 419   if (!err.Success()) {
 420     diagnostic_manager.PutString(eDiagnosticSeverityWarning, err.AsCString());
 421   }
 422
 423   ////////////////////////////////////
 424   // Generate the expression
 425   //
 426
 427   ApplyObjcCastHack(m_expr_text);
 428
 429   SetupDeclVendor(exe_ctx, m_target);
 430   return true;
 431 }
 432
 433 bool ClangUserExpression::Parse(DiagnosticManager &diagnostic_manager,
 434                                 ExecutionContext &exe_ctx,
 435                                 lldb_private::ExecutionPolicy execution_policy,
 436                                 bool keep_result_in_memory,
 437                                 bool generate_debug_info) {
 438   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
 439
 440   if (!PrepareForParsing(diagnostic_manager, exe_ctx))
 441     return false;
 442
 443   lldb::LanguageType lang_type = lldb::LanguageType::eLanguageTypeUnknown;
 444   if (auto new_lang = GetLanguageForExpr(diagnostic_manager, exe_ctx)) {
 445     lang_type = new_lang.getValue();
 446   }
 447
 448   if (log)
 449     log->Printf("Parsing the following code:\n%s", m_transformed_text.c_str());
 450
 451   ////////////////////////////////////
 452   // Set up the target and compiler
 453   //
 454
 455   Target *target = exe_ctx.GetTargetPtr();
 456
 457   if (!target) {
 458     diagnostic_manager.PutString(eDiagnosticSeverityError, "invalid target");
 459     return false;
 460   }
 461
 462   //////////////////////////
 463   // Parse the expression
 464   //
 465
 466   m_materializer_ap.reset(new Materializer());
 467
 468   ResetDeclMap(exe_ctx, m_result_delegate, keep_result_in_memory);
 469
 470   OnExit on_exit([this]() { ResetDeclMap(); });
 471
 472   if (!DeclMap()->WillParse(exe_ctx, m_materializer_ap.get())) {
 473     diagnostic_manager.PutString(
 474         eDiagnosticSeverityError,
 475         "current process state is unsuitable for expression parsing");
 476     return false;
 477   }
 478
 479   if (m_options.GetExecutionPolicy() == eExecutionPolicyTopLevel) {
 480     DeclMap()->SetLookupsEnabled(true);
 481   }
 482
 483   Process *process = exe_ctx.GetProcessPtr();
 484   ExecutionContextScope *exe_scope = process;
 485
 486   if (!exe_scope)
 487     exe_scope = exe_ctx.GetTargetPtr();
 488
 489   // We use a shared pointer here so we can use the original parser - if it
 490   // succeeds or the rewrite parser we might make if it fails.  But the
 491   // parser_sp will never be empty.
 492
 493   ClangExpressionParser parser(exe_scope, *this, generate_debug_info);
 494
 495   unsigned num_errors = parser.Parse(diagnostic_manager);
 496
 497   // Check here for FixItHints.  If there are any try to apply the fixits and
 498   // set the fixed text in m_fixed_text before returning an error.
 499   if (num_errors) {
 500     if (diagnostic_manager.HasFixIts()) {
 501       if (parser.RewriteExpression(diagnostic_manager)) {
 502         size_t fixed_start;
 503         size_t fixed_end;
 504         const std::string &fixed_expression =
 505             diagnostic_manager.GetFixedExpression();
 506         if (ExpressionSourceCode::GetOriginalBodyBounds(
 507                 fixed_expression, lang_type, fixed_start, fixed_end))
 508           m_fixed_text =
 509               fixed_expression.substr(fixed_start, fixed_end - fixed_start);
 510       }
 511     }
 512     return false;
 513   }
 514
 515   //////////////////////////////////////////////////////////////////////////////////////////
 516   // Prepare the output of the parser for execution, evaluating it statically
 517   // if possible
 518   //
 519
 520   {
 521     Status jit_error = parser.PrepareForExecution(
 522         m_jit_start_addr, m_jit_end_addr, m_execution_unit_sp, exe_ctx,
 523         m_can_interpret, execution_policy);
 524
 525     if (!jit_error.Success()) {
 526       const char *error_cstr = jit_error.AsCString();
 527       if (error_cstr && error_cstr[0])
 528         diagnostic_manager.PutString(eDiagnosticSeverityError, error_cstr);
 529       else
 530         diagnostic_manager.PutString(eDiagnosticSeverityError,
 531                                      "expression can't be interpreted or run");
 532       return false;
 533     }
 534   }
 535
 536   if (exe_ctx.GetProcessPtr() && execution_policy == eExecutionPolicyTopLevel) {
 537     Status static_init_error =
 538         parser.RunStaticInitializers(m_execution_unit_sp, exe_ctx);
 539
 540     if (!static_init_error.Success()) {
 541       const char *error_cstr = static_init_error.AsCString();
 542       if (error_cstr && error_cstr[0])
 543         diagnostic_manager.Printf(eDiagnosticSeverityError,
 544                                   "couldn't run static initializers: %s\n",
 545                                   error_cstr);
 546       else
 547         diagnostic_manager.PutString(eDiagnosticSeverityError,
 548                                      "couldn't run static initializers\n");
 549       return false;
 550     }
 551   }
 552
 553   if (m_execution_unit_sp) {
 554     bool register_execution_unit = false;
 555
 556     if (m_options.GetExecutionPolicy() == eExecutionPolicyTopLevel) {
 557       register_execution_unit = true;
 558     }
 559
 560     // If there is more than one external function in the execution unit, it
 561     // needs to keep living even if it's not top level, because the result
 562     // could refer to that function.
 563
 564     if (m_execution_unit_sp->GetJittedFunctions().size() > 1) {
 565       register_execution_unit = true;
 566     }
 567
 568     if (register_execution_unit) {
 569       llvm::cast<PersistentExpressionState>(
 570           exe_ctx.GetTargetPtr()->GetPersistentExpressionStateForLanguage(
 571               m_language))
 572           ->RegisterExecutionUnit(m_execution_unit_sp);
 573     }
 574   }
 575
 576   if (generate_debug_info) {
 577     lldb::ModuleSP jit_module_sp(m_execution_unit_sp->GetJITModule());
 578
 579     if (jit_module_sp) {
 580       ConstString const_func_name(FunctionName());
 581       FileSpec jit_file;
 582       jit_file.GetFilename() = const_func_name;
 583       jit_module_sp->SetFileSpecAndObjectName(jit_file, ConstString());
 584       m_jit_module_wp = jit_module_sp;
 585       target->GetImages().Append(jit_module_sp);
 586     }
 587   }
 588
 589   if (process && m_jit_start_addr != LLDB_INVALID_ADDRESS)
 590     m_jit_process_wp = lldb::ProcessWP(process->shared_from_this());
 591   return true;
 592 }
 593
 594 bool ClangUserExpression::AddArguments(ExecutionContext &exe_ctx,
 595                                        std::vector<lldb::addr_t> &args,
 596                                        lldb::addr_t struct_address,
 597                                        DiagnosticManager &diagnostic_manager) {
 598   lldb::addr_t object_ptr = LLDB_INVALID_ADDRESS;
 599   lldb::addr_t cmd_ptr = LLDB_INVALID_ADDRESS;
 600
 601   if (m_needs_object_ptr) {
 602     lldb::StackFrameSP frame_sp = exe_ctx.GetFrameSP();
 603     if (!frame_sp)
 604       return true;
 605
 606     ConstString object_name;
 607
 608     if (m_in_cplusplus_method) {
 609       object_name.SetCString("this");
 610     } else if (m_in_objectivec_method) {
 611       object_name.SetCString("self");
 612     } else {
 613       diagnostic_manager.PutString(
 614           eDiagnosticSeverityError,
 615           "need object pointer but don't know the language");
 616       return false;
 617     }
 618
 619     Status object_ptr_error;
 620
 621     object_ptr = GetObjectPointer(frame_sp, object_name, object_ptr_error);
 622
 623     if (!object_ptr_error.Success()) {
 624       exe_ctx.GetTargetRef().GetDebugger().GetAsyncOutputStream()->Printf(
 625           "warning: `%s' is not accessible (substituting 0)\n",
 626           object_name.AsCString());
 627       object_ptr = 0;
 628     }
 629
 630     if (m_in_objectivec_method) {
 631       ConstString cmd_name("_cmd");
 632
 633       cmd_ptr = GetObjectPointer(frame_sp, cmd_name, object_ptr_error);
 634
 635       if (!object_ptr_error.Success()) {
 636         diagnostic_manager.Printf(
 637             eDiagnosticSeverityWarning,
 638             "couldn't get cmd pointer (substituting NULL): %s",
 639             object_ptr_error.AsCString());
 640         cmd_ptr = 0;
 641       }
 642     }
 643
 644     args.push_back(object_ptr);
 645
 646     if (m_in_objectivec_method)
 647       args.push_back(cmd_ptr);
 648
 649     args.push_back(struct_address);
 650   } else {
 651     args.push_back(struct_address);
 652   }
 653   return true;
 654 }
 655
 656 lldb::ExpressionVariableSP ClangUserExpression::GetResultAfterDematerialization(
 657     ExecutionContextScope *exe_scope) {
 658   return m_result_delegate.GetVariable();
 659 }
 660
 661 void ClangUserExpression::ClangUserExpressionHelper::ResetDeclMap(
 662     ExecutionContext &exe_ctx,
 663     Materializer::PersistentVariableDelegate &delegate,
 664     bool keep_result_in_memory) {
 665   m_expr_decl_map_up.reset(
 666       new ClangExpressionDeclMap(keep_result_in_memory, &delegate, exe_ctx));
 667 }
 668
 669 clang::ASTConsumer *
 670 ClangUserExpression::ClangUserExpressionHelper::ASTTransformer(
 671     clang::ASTConsumer *passthrough) {
 672   m_result_synthesizer_up.reset(
 673       new ASTResultSynthesizer(passthrough, m_top_level, m_target));
 674
 675   return m_result_synthesizer_up.get();
 676 }
 677
 678 void ClangUserExpression::ClangUserExpressionHelper::CommitPersistentDecls() {
 679   if (m_result_synthesizer_up.get()) {
 680     m_result_synthesizer_up->CommitPersistentDecls();
 681   }
 682 }
 683
 684 ConstString ClangUserExpression::ResultDelegate::GetName() {
 685   auto prefix = m_persistent_state->GetPersistentVariablePrefix();
 686   return m_persistent_state->GetNextPersistentVariableName(*m_target_sp,
 687                                                            prefix);
 688 }
 689
 690 void ClangUserExpression::ResultDelegate::DidDematerialize(
 691     lldb::ExpressionVariableSP &variable) {
 692   m_variable = variable;
 693 }
 694
 695 void ClangUserExpression::ResultDelegate::RegisterPersistentState(
 696     PersistentExpressionState *persistent_state) {
 697   m_persistent_state = persistent_state;
 698 }
 699
 700 lldb::ExpressionVariableSP &ClangUserExpression::ResultDelegate::GetVariable() {
 701   return m_variable;
 702 }