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