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 <string> 17 #include <map> 18 19 #include "ClangUserExpression.h" 20 21 #include "ASTResultSynthesizer.h" 22 #include "ClangExpressionDeclMap.h" 23 #include "ClangExpressionParser.h" 24 #include "ClangModulesDeclVendor.h" 25 #include "ClangPersistentVariables.h" 26 27 #include "lldb/Core/ConstString.h" 28 #include "lldb/Core/Log.h" 29 #include "lldb/Core/Module.h" 30 #include "lldb/Core/StreamFile.h" 31 #include "lldb/Core/StreamString.h" 32 #include "lldb/Core/ValueObjectConstResult.h" 33 #include "lldb/Expression/ExpressionSourceCode.h" 34 #include "lldb/Expression/IRExecutionUnit.h" 35 #include "lldb/Expression/IRInterpreter.h" 36 #include "lldb/Expression/Materializer.h" 37 #include "lldb/Host/HostInfo.h" 38 #include "lldb/Symbol/Block.h" 39 #include "lldb/Symbol/ClangASTContext.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/ClangExternalASTSourceCommon.h" 45 #include "lldb/Symbol/VariableList.h" 46 #include "lldb/Target/ExecutionContext.h" 47 #include "lldb/Target/Process.h" 48 #include "lldb/Target/StackFrame.h" 49 #include "lldb/Target/Target.h" 50 #include "lldb/Target/ThreadPlan.h" 51 #include "lldb/Target/ThreadPlanCallUserExpression.h" 52 53 #include "clang/AST/DeclCXX.h" 54 #include "clang/AST/DeclObjC.h" 55 56 using namespace lldb_private; 57 58 ClangUserExpression::ClangUserExpression (ExecutionContextScope &exe_scope, 59 const char *expr, 60 const char *expr_prefix, 61 lldb::LanguageType language, 62 ResultType desired_type) : 63 UserExpression (exe_scope, expr, expr_prefix, language, desired_type), 64 m_type_system_helper(*m_target_wp.lock().get()) 65 { 66 switch (m_language) 67 { 68 case lldb::eLanguageTypeC_plus_plus: 69 m_allow_cxx = true; 70 break; 71 case lldb::eLanguageTypeObjC: 72 m_allow_objc = true; 73 break; 74 case lldb::eLanguageTypeObjC_plus_plus: 75 default: 76 m_allow_cxx = true; 77 m_allow_objc = true; 78 break; 79 } 80 } 81 82 ClangUserExpression::~ClangUserExpression () 83 { 84 } 85 86 void 87 ClangUserExpression::ScanContext(ExecutionContext &exe_ctx, Error &err) 88 { 89 Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); 90 91 if (log) 92 log->Printf("ClangUserExpression::ScanContext()"); 93 94 m_target = exe_ctx.GetTargetPtr(); 95 96 if (!(m_allow_cxx || m_allow_objc)) 97 { 98 if (log) 99 log->Printf(" [CUE::SC] Settings inhibit C++ and Objective-C"); 100 return; 101 } 102 103 StackFrame *frame = exe_ctx.GetFramePtr(); 104 if (frame == NULL) 105 { 106 if (log) 107 log->Printf(" [CUE::SC] Null stack frame"); 108 return; 109 } 110 111 SymbolContext sym_ctx = frame->GetSymbolContext(lldb::eSymbolContextFunction | lldb::eSymbolContextBlock); 112 113 if (!sym_ctx.function) 114 { 115 if (log) 116 log->Printf(" [CUE::SC] Null function"); 117 return; 118 } 119 120 // Find the block that defines the function represented by "sym_ctx" 121 Block *function_block = sym_ctx.GetFunctionBlock(); 122 123 if (!function_block) 124 { 125 if (log) 126 log->Printf(" [CUE::SC] Null function block"); 127 return; 128 } 129 130 CompilerDeclContext decl_context = function_block->GetDeclContext(); 131 132 if (!decl_context) 133 { 134 if (log) 135 log->Printf(" [CUE::SC] Null decl context"); 136 return; 137 } 138 139 if (clang::CXXMethodDecl *method_decl = ClangASTContext::DeclContextGetAsCXXMethodDecl(decl_context)) 140 { 141 if (m_allow_cxx && method_decl->isInstance()) 142 { 143 if (m_enforce_valid_object) 144 { 145 lldb::VariableListSP variable_list_sp (function_block->GetBlockVariableList (true)); 146 147 const char *thisErrorString = "Stopped in a C++ method, but 'this' isn't available; pretending we are in a generic context"; 148 149 if (!variable_list_sp) 150 { 151 err.SetErrorString(thisErrorString); 152 return; 153 } 154 155 lldb::VariableSP this_var_sp (variable_list_sp->FindVariable(ConstString("this"))); 156 157 if (!this_var_sp || 158 !this_var_sp->IsInScope(frame) || 159 !this_var_sp->LocationIsValidForFrame (frame)) 160 { 161 err.SetErrorString(thisErrorString); 162 return; 163 } 164 } 165 166 m_in_cplusplus_method = true; 167 m_needs_object_ptr = true; 168 } 169 } 170 else if (clang::ObjCMethodDecl *method_decl = ClangASTContext::DeclContextGetAsObjCMethodDecl(decl_context)) 171 { 172 if (m_allow_objc) 173 { 174 if (m_enforce_valid_object) 175 { 176 lldb::VariableListSP variable_list_sp (function_block->GetBlockVariableList (true)); 177 178 const char *selfErrorString = "Stopped in an Objective-C method, but 'self' isn't available; pretending we are in a generic context"; 179 180 if (!variable_list_sp) 181 { 182 err.SetErrorString(selfErrorString); 183 return; 184 } 185 186 lldb::VariableSP self_variable_sp = variable_list_sp->FindVariable(ConstString("self")); 187 188 if (!self_variable_sp || 189 !self_variable_sp->IsInScope(frame) || 190 !self_variable_sp->LocationIsValidForFrame (frame)) 191 { 192 err.SetErrorString(selfErrorString); 193 return; 194 } 195 } 196 197 m_in_objectivec_method = true; 198 m_needs_object_ptr = true; 199 200 if (!method_decl->isInstanceMethod()) 201 m_in_static_method = true; 202 } 203 } 204 else if (clang::FunctionDecl *function_decl = ClangASTContext::DeclContextGetAsFunctionDecl(decl_context)) 205 { 206 // We might also have a function that said in the debug information that it captured an 207 // object pointer. The best way to deal with getting to the ivars at present is by pretending 208 // that this is a method of a class in whatever runtime the debug info says the object pointer 209 // belongs to. Do that here. 210 211 ClangASTMetadata *metadata = ClangASTContext::DeclContextGetMetaData (decl_context, function_decl); 212 if (metadata && metadata->HasObjectPtr()) 213 { 214 lldb::LanguageType language = metadata->GetObjectPtrLanguage(); 215 if (language == lldb::eLanguageTypeC_plus_plus) 216 { 217 if (m_enforce_valid_object) 218 { 219 lldb::VariableListSP variable_list_sp (function_block->GetBlockVariableList (true)); 220 221 const char *thisErrorString = "Stopped in a context claiming to capture a C++ object pointer, but 'this' isn't available; pretending we are in a generic context"; 222 223 if (!variable_list_sp) 224 { 225 err.SetErrorString(thisErrorString); 226 return; 227 } 228 229 lldb::VariableSP this_var_sp (variable_list_sp->FindVariable(ConstString("this"))); 230 231 if (!this_var_sp || 232 !this_var_sp->IsInScope(frame) || 233 !this_var_sp->LocationIsValidForFrame (frame)) 234 { 235 err.SetErrorString(thisErrorString); 236 return; 237 } 238 } 239 240 m_in_cplusplus_method = true; 241 m_needs_object_ptr = true; 242 } 243 else if (language == lldb::eLanguageTypeObjC) 244 { 245 if (m_enforce_valid_object) 246 { 247 lldb::VariableListSP variable_list_sp (function_block->GetBlockVariableList (true)); 248 249 const char *selfErrorString = "Stopped in a context claiming to capture an Objective-C object pointer, but 'self' isn't available; pretending we are in a generic context"; 250 251 if (!variable_list_sp) 252 { 253 err.SetErrorString(selfErrorString); 254 return; 255 } 256 257 lldb::VariableSP self_variable_sp = variable_list_sp->FindVariable(ConstString("self")); 258 259 if (!self_variable_sp || 260 !self_variable_sp->IsInScope(frame) || 261 !self_variable_sp->LocationIsValidForFrame (frame)) 262 { 263 err.SetErrorString(selfErrorString); 264 return; 265 } 266 267 Type *self_type = self_variable_sp->GetType(); 268 269 if (!self_type) 270 { 271 err.SetErrorString(selfErrorString); 272 return; 273 } 274 275 CompilerType self_clang_type = self_type->GetForwardCompilerType (); 276 277 if (!self_clang_type) 278 { 279 err.SetErrorString(selfErrorString); 280 return; 281 } 282 283 if (ClangASTContext::IsObjCClassType(self_clang_type)) 284 { 285 return; 286 } 287 else if (ClangASTContext::IsObjCObjectPointerType(self_clang_type)) 288 { 289 m_in_objectivec_method = true; 290 m_needs_object_ptr = true; 291 } 292 else 293 { 294 err.SetErrorString(selfErrorString); 295 return; 296 } 297 } 298 else 299 { 300 m_in_objectivec_method = true; 301 m_needs_object_ptr = true; 302 } 303 } 304 } 305 } 306 } 307 308 // This is a really nasty hack, meant to fix Objective-C expressions of the form 309 // (int)[myArray count]. Right now, because the type information for count is 310 // not available, [myArray count] returns id, which can't be directly cast to 311 // int without causing a clang error. 312 static void 313 ApplyObjcCastHack(std::string &expr) 314 { 315 #define OBJC_CAST_HACK_FROM "(int)[" 316 #define OBJC_CAST_HACK_TO "(int)(long long)[" 317 318 size_t from_offset; 319 320 while ((from_offset = expr.find(OBJC_CAST_HACK_FROM)) != expr.npos) 321 expr.replace(from_offset, sizeof(OBJC_CAST_HACK_FROM) - 1, OBJC_CAST_HACK_TO); 322 323 #undef OBJC_CAST_HACK_TO 324 #undef OBJC_CAST_HACK_FROM 325 } 326 327 bool 328 ClangUserExpression::Parse (Stream &error_stream, 329 ExecutionContext &exe_ctx, 330 lldb_private::ExecutionPolicy execution_policy, 331 bool keep_result_in_memory, 332 bool generate_debug_info) 333 { 334 Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); 335 336 Error err; 337 338 InstallContext(exe_ctx); 339 340 ScanContext(exe_ctx, err); 341 342 if (!err.Success()) 343 { 344 error_stream.Printf("warning: %s\n", err.AsCString()); 345 } 346 347 StreamString m_transformed_stream; 348 349 //////////////////////////////////// 350 // Generate the expression 351 // 352 353 ApplyObjcCastHack(m_expr_text); 354 //ApplyUnicharHack(m_expr_text); 355 356 std::string prefix = m_expr_prefix; 357 358 if (ClangModulesDeclVendor *decl_vendor = m_target->GetClangModulesDeclVendor()) 359 { 360 const ClangModulesDeclVendor::ModuleVector &hand_imported_modules = llvm::cast<ClangPersistentVariables>(m_target->GetScratchTypeSystemForLanguage(lldb::eLanguageTypeC)->GetPersistentExpressionState())->GetHandLoadedClangModules(); 361 ClangModulesDeclVendor::ModuleVector modules_for_macros; 362 363 for (ClangModulesDeclVendor::ModuleID module : hand_imported_modules) 364 { 365 modules_for_macros.push_back(module); 366 } 367 368 if (m_target->GetEnableAutoImportClangModules()) 369 { 370 if (StackFrame *frame = exe_ctx.GetFramePtr()) 371 { 372 if (Block *block = frame->GetFrameBlock()) 373 { 374 SymbolContext sc; 375 376 block->CalculateSymbolContext(&sc); 377 378 if (sc.comp_unit) 379 { 380 StreamString error_stream; 381 382 decl_vendor->AddModulesForCompileUnit(*sc.comp_unit, modules_for_macros, error_stream); 383 } 384 } 385 } 386 } 387 } 388 389 std::unique_ptr<ExpressionSourceCode> source_code (ExpressionSourceCode::CreateWrapped(prefix.c_str(), m_expr_text.c_str())); 390 391 lldb::LanguageType lang_type; 392 393 if (m_in_cplusplus_method) 394 lang_type = lldb::eLanguageTypeC_plus_plus; 395 else if (m_in_objectivec_method) 396 lang_type = lldb::eLanguageTypeObjC; 397 else 398 lang_type = lldb::eLanguageTypeC; 399 400 if (!source_code->GetText(m_transformed_text, lang_type, m_const_object, m_in_static_method, exe_ctx)) 401 { 402 error_stream.PutCString ("error: couldn't construct expression body"); 403 return false; 404 } 405 406 if (log) 407 log->Printf("Parsing the following code:\n%s", m_transformed_text.c_str()); 408 409 //////////////////////////////////// 410 // Set up the target and compiler 411 // 412 413 Target *target = exe_ctx.GetTargetPtr(); 414 415 if (!target) 416 { 417 error_stream.PutCString ("error: invalid target\n"); 418 return false; 419 } 420 421 ////////////////////////// 422 // Parse the expression 423 // 424 425 m_materializer_ap.reset(new Materializer()); 426 427 ResetDeclMap(exe_ctx, keep_result_in_memory); 428 429 class OnExit 430 { 431 public: 432 typedef std::function <void (void)> Callback; 433 434 OnExit (Callback const &callback) : 435 m_callback(callback) 436 { 437 } 438 439 ~OnExit () 440 { 441 m_callback(); 442 } 443 private: 444 Callback m_callback; 445 }; 446 447 OnExit on_exit([this]() { ResetDeclMap(); }); 448 449 if (!DeclMap()->WillParse(exe_ctx, m_materializer_ap.get())) 450 { 451 error_stream.PutCString ("error: current process state is unsuitable for expression parsing\n"); 452 453 ResetDeclMap(); // We are being careful here in the case of breakpoint conditions. 454 455 return false; 456 } 457 458 Process *process = exe_ctx.GetProcessPtr(); 459 ExecutionContextScope *exe_scope = process; 460 461 if (!exe_scope) 462 exe_scope = exe_ctx.GetTargetPtr(); 463 464 ClangExpressionParser parser(exe_scope, *this, generate_debug_info); 465 466 unsigned num_errors = parser.Parse (error_stream); 467 468 if (num_errors) 469 { 470 error_stream.Printf ("error: %d errors parsing expression\n", num_errors); 471 472 ResetDeclMap(); // We are being careful here in the case of breakpoint conditions. 473 474 return false; 475 } 476 477 ////////////////////////////////////////////////////////////////////////////////////////// 478 // Prepare the output of the parser for execution, evaluating it statically if possible 479 // 480 481 Error jit_error = parser.PrepareForExecution (m_jit_start_addr, 482 m_jit_end_addr, 483 m_execution_unit_sp, 484 exe_ctx, 485 m_can_interpret, 486 execution_policy); 487 488 if (generate_debug_info) 489 { 490 lldb::ModuleSP jit_module_sp ( m_execution_unit_sp->GetJITModule()); 491 492 if (jit_module_sp) 493 { 494 ConstString const_func_name(FunctionName()); 495 FileSpec jit_file; 496 jit_file.GetFilename() = const_func_name; 497 jit_module_sp->SetFileSpecAndObjectName (jit_file, ConstString()); 498 m_jit_module_wp = jit_module_sp; 499 target->GetImages().Append(jit_module_sp); 500 } 501 // lldb_private::ObjectFile *jit_obj_file = jit_module_sp->GetObjectFile(); 502 // StreamFile strm (stdout, false); 503 // if (jit_obj_file) 504 // { 505 // jit_obj_file->GetSectionList(); 506 // jit_obj_file->GetSymtab(); 507 // jit_obj_file->Dump(&strm); 508 // } 509 // lldb_private::SymbolVendor *jit_sym_vendor = jit_module_sp->GetSymbolVendor(); 510 // if (jit_sym_vendor) 511 // { 512 // lldb_private::SymbolContextList sc_list; 513 // jit_sym_vendor->FindFunctions(const_func_name, NULL, lldb::eFunctionNameTypeFull, true, false, sc_list); 514 // sc_list.Dump(&strm, target); 515 // jit_sym_vendor->Dump(&strm); 516 // } 517 } 518 519 ResetDeclMap(); // Make this go away since we don't need any of its state after parsing. This also gets rid of any ClangASTImporter::Minions. 520 521 if (jit_error.Success()) 522 { 523 if (process && m_jit_start_addr != LLDB_INVALID_ADDRESS) 524 m_jit_process_wp = lldb::ProcessWP(process->shared_from_this()); 525 return true; 526 } 527 else 528 { 529 const char *error_cstr = jit_error.AsCString(); 530 if (error_cstr && error_cstr[0]) 531 error_stream.Printf ("error: %s\n", error_cstr); 532 else 533 error_stream.Printf ("error: expression can't be interpreted or run\n"); 534 return false; 535 } 536 } 537 538 bool 539 ClangUserExpression::AddInitialArguments (ExecutionContext &exe_ctx, 540 std::vector<lldb::addr_t> &args, 541 Stream &error_stream) 542 { 543 lldb::addr_t object_ptr = LLDB_INVALID_ADDRESS; 544 lldb::addr_t cmd_ptr = LLDB_INVALID_ADDRESS; 545 546 if (m_needs_object_ptr) 547 { 548 lldb::StackFrameSP frame_sp = exe_ctx.GetFrameSP(); 549 if (!frame_sp) 550 return true; 551 552 ConstString object_name; 553 554 if (m_in_cplusplus_method) 555 { 556 object_name.SetCString("this"); 557 } 558 else if (m_in_objectivec_method) 559 { 560 object_name.SetCString("self"); 561 } 562 else 563 { 564 error_stream.Printf("Need object pointer but don't know the language\n"); 565 return false; 566 } 567 568 Error object_ptr_error; 569 570 object_ptr = GetObjectPointer(frame_sp, object_name, object_ptr_error); 571 572 if (!object_ptr_error.Success()) 573 { 574 error_stream.Printf("warning: couldn't get required object pointer (substituting NULL): %s\n", object_ptr_error.AsCString()); 575 object_ptr = 0; 576 } 577 578 if (m_in_objectivec_method) 579 { 580 ConstString cmd_name("_cmd"); 581 582 cmd_ptr = GetObjectPointer(frame_sp, cmd_name, object_ptr_error); 583 584 if (!object_ptr_error.Success()) 585 { 586 error_stream.Printf("warning: couldn't get cmd pointer (substituting NULL): %s\n", object_ptr_error.AsCString()); 587 cmd_ptr = 0; 588 } 589 } 590 if (object_ptr) 591 args.push_back(object_ptr); 592 593 if (m_in_objectivec_method) 594 args.push_back(cmd_ptr); 595 596 597 } 598 return true; 599 } 600 601 void 602 ClangUserExpression::ClangUserExpressionHelper::ResetDeclMap(ExecutionContext &exe_ctx, bool keep_result_in_memory) 603 { 604 m_expr_decl_map_up.reset(new ClangExpressionDeclMap(keep_result_in_memory, exe_ctx)); 605 } 606 607 clang::ASTConsumer * 608 ClangUserExpression::ClangUserExpressionHelper::ASTTransformer (clang::ASTConsumer *passthrough) 609 { 610 m_result_synthesizer_up.reset(new ASTResultSynthesizer(passthrough, 611 m_target)); 612 613 return m_result_synthesizer_up.get(); 614 } 615 616