1 //===-- ClangExpressionSourceCode.cpp ---------------------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "ClangExpressionSourceCode.h" 10 11 #include "clang/Basic/CharInfo.h" 12 #include "clang/Basic/SourceManager.h" 13 #include "clang/Lex/Lexer.h" 14 #include "llvm/ADT/StringRef.h" 15 16 #include "Plugins/ExpressionParser/Clang/ClangModulesDeclVendor.h" 17 #include "Plugins/ExpressionParser/Clang/ClangPersistentVariables.h" 18 #include "lldb/Symbol/Block.h" 19 #include "lldb/Symbol/CompileUnit.h" 20 #include "lldb/Symbol/DebugMacros.h" 21 #include "lldb/Symbol/TypeSystem.h" 22 #include "lldb/Symbol/VariableList.h" 23 #include "lldb/Target/ExecutionContext.h" 24 #include "lldb/Target/Language.h" 25 #include "lldb/Target/Platform.h" 26 #include "lldb/Target/StackFrame.h" 27 #include "lldb/Target/Target.h" 28 #include "lldb/Utility/StreamString.h" 29 30 using namespace lldb_private; 31 32 #define PREFIX_NAME "<lldb wrapper prefix>" 33 34 const llvm::StringRef ClangExpressionSourceCode::g_prefix_file_name = PREFIX_NAME; 35 36 const char *ClangExpressionSourceCode::g_expression_prefix = 37 "#line 1 \"" PREFIX_NAME R"(" 38 #ifndef offsetof 39 #define offsetof(t, d) __builtin_offsetof(t, d) 40 #endif 41 #ifndef NULL 42 #define NULL (__null) 43 #endif 44 #ifndef Nil 45 #define Nil (__null) 46 #endif 47 #ifndef nil 48 #define nil (__null) 49 #endif 50 #ifndef YES 51 #define YES ((BOOL)1) 52 #endif 53 #ifndef NO 54 #define NO ((BOOL)0) 55 #endif 56 typedef __INT8_TYPE__ int8_t; 57 typedef __UINT8_TYPE__ uint8_t; 58 typedef __INT16_TYPE__ int16_t; 59 typedef __UINT16_TYPE__ uint16_t; 60 typedef __INT32_TYPE__ int32_t; 61 typedef __UINT32_TYPE__ uint32_t; 62 typedef __INT64_TYPE__ int64_t; 63 typedef __UINT64_TYPE__ uint64_t; 64 typedef __INTPTR_TYPE__ intptr_t; 65 typedef __UINTPTR_TYPE__ uintptr_t; 66 typedef __SIZE_TYPE__ size_t; 67 typedef __PTRDIFF_TYPE__ ptrdiff_t; 68 typedef unsigned short unichar; 69 extern "C" 70 { 71 int printf(const char * __restrict, ...); 72 } 73 )"; 74 75 namespace { 76 77 class AddMacroState { 78 enum State { 79 CURRENT_FILE_NOT_YET_PUSHED, 80 CURRENT_FILE_PUSHED, 81 CURRENT_FILE_POPPED 82 }; 83 84 public: 85 AddMacroState(const FileSpec ¤t_file, const uint32_t current_file_line) 86 : m_state(CURRENT_FILE_NOT_YET_PUSHED), m_current_file(current_file), 87 m_current_file_line(current_file_line) {} 88 89 void StartFile(const FileSpec &file) { 90 m_file_stack.push_back(file); 91 if (file == m_current_file) 92 m_state = CURRENT_FILE_PUSHED; 93 } 94 95 void EndFile() { 96 if (m_file_stack.size() == 0) 97 return; 98 99 FileSpec old_top = m_file_stack.back(); 100 m_file_stack.pop_back(); 101 if (old_top == m_current_file) 102 m_state = CURRENT_FILE_POPPED; 103 } 104 105 // An entry is valid if it occurs before the current line in the current 106 // file. 107 bool IsValidEntry(uint32_t line) { 108 switch (m_state) { 109 case CURRENT_FILE_NOT_YET_PUSHED: 110 return true; 111 case CURRENT_FILE_PUSHED: 112 // If we are in file included in the current file, the entry should be 113 // added. 114 if (m_file_stack.back() != m_current_file) 115 return true; 116 117 return line < m_current_file_line; 118 default: 119 return false; 120 } 121 } 122 123 private: 124 std::vector<FileSpec> m_file_stack; 125 State m_state; 126 FileSpec m_current_file; 127 uint32_t m_current_file_line; 128 }; 129 130 } // anonymous namespace 131 132 static void AddMacros(const DebugMacros *dm, CompileUnit *comp_unit, 133 AddMacroState &state, StreamString &stream) { 134 if (dm == nullptr) 135 return; 136 137 for (size_t i = 0; i < dm->GetNumMacroEntries(); i++) { 138 const DebugMacroEntry &entry = dm->GetMacroEntryAtIndex(i); 139 uint32_t line; 140 141 switch (entry.GetType()) { 142 case DebugMacroEntry::DEFINE: 143 if (state.IsValidEntry(entry.GetLineNumber())) 144 stream.Printf("#define %s\n", entry.GetMacroString().AsCString()); 145 else 146 return; 147 break; 148 case DebugMacroEntry::UNDEF: 149 if (state.IsValidEntry(entry.GetLineNumber())) 150 stream.Printf("#undef %s\n", entry.GetMacroString().AsCString()); 151 else 152 return; 153 break; 154 case DebugMacroEntry::START_FILE: 155 line = entry.GetLineNumber(); 156 if (state.IsValidEntry(line)) 157 state.StartFile(entry.GetFileSpec(comp_unit)); 158 else 159 return; 160 break; 161 case DebugMacroEntry::END_FILE: 162 state.EndFile(); 163 break; 164 case DebugMacroEntry::INDIRECT: 165 AddMacros(entry.GetIndirectDebugMacros(), comp_unit, state, stream); 166 break; 167 default: 168 // This is an unknown/invalid entry. Ignore. 169 break; 170 } 171 } 172 } 173 174 lldb_private::ClangExpressionSourceCode::ClangExpressionSourceCode( 175 llvm::StringRef filename, llvm::StringRef name, llvm::StringRef prefix, 176 llvm::StringRef body, Wrapping wrap) 177 : ExpressionSourceCode(name, prefix, body, wrap) { 178 // Use #line markers to pretend that we have a single-line source file 179 // containing only the user expression. This will hide our wrapper code 180 // from the user when we render diagnostics with Clang. 181 m_start_marker = "#line 1 \"" + filename.str() + "\"\n"; 182 m_end_marker = "\n;\n#line 1 \"<lldb wrapper suffix>\"\n"; 183 } 184 185 namespace { 186 /// Allows checking if a token is contained in a given expression. 187 class TokenVerifier { 188 /// The tokens we found in the expression. 189 llvm::StringSet<> m_tokens; 190 191 public: 192 TokenVerifier(std::string body); 193 /// Returns true iff the given expression body contained a token with the 194 /// given content. 195 bool hasToken(llvm::StringRef token) const { 196 return m_tokens.find(token) != m_tokens.end(); 197 } 198 }; 199 } // namespace 200 201 TokenVerifier::TokenVerifier(std::string body) { 202 using namespace clang; 203 204 // We only care about tokens and not their original source locations. If we 205 // move the whole expression to only be in one line we can simplify the 206 // following code that extracts the token contents. 207 std::replace(body.begin(), body.end(), '\n', ' '); 208 std::replace(body.begin(), body.end(), '\r', ' '); 209 210 FileSystemOptions file_opts; 211 FileManager file_mgr(file_opts, 212 FileSystem::Instance().GetVirtualFileSystem()); 213 214 // Let's build the actual source code Clang needs and setup some utility 215 // objects. 216 llvm::IntrusiveRefCntPtr<DiagnosticIDs> diag_ids(new DiagnosticIDs()); 217 llvm::IntrusiveRefCntPtr<DiagnosticOptions> diags_opts( 218 new DiagnosticOptions()); 219 DiagnosticsEngine diags(diag_ids, diags_opts); 220 clang::SourceManager SM(diags, file_mgr); 221 auto buf = llvm::MemoryBuffer::getMemBuffer(body); 222 223 FileID FID = SM.createFileID(clang::SourceManager::Unowned, buf.get()); 224 225 // Let's just enable the latest ObjC and C++ which should get most tokens 226 // right. 227 LangOptions Opts; 228 Opts.ObjC = true; 229 Opts.DollarIdents = true; 230 Opts.CPlusPlus17 = true; 231 Opts.LineComment = true; 232 233 Lexer lex(FID, buf.get(), SM, Opts); 234 235 Token token; 236 bool exit = false; 237 while (!exit) { 238 // Returns true if this is the last token we get from the lexer. 239 exit = lex.LexFromRawLexer(token); 240 241 // Extract the column number which we need to extract the token content. 242 // Our expression is just one line, so we don't need to handle any line 243 // numbers here. 244 bool invalid = false; 245 unsigned start = SM.getSpellingColumnNumber(token.getLocation(), &invalid); 246 if (invalid) 247 continue; 248 // Column numbers start at 1, but indexes in our string start at 0. 249 --start; 250 251 // Annotations don't have a length, so let's skip them. 252 if (token.isAnnotation()) 253 continue; 254 255 // Extract the token string from our source code and store it. 256 std::string token_str = body.substr(start, token.getLength()); 257 if (token_str.empty()) 258 continue; 259 m_tokens.insert(token_str); 260 } 261 } 262 263 static void AddLocalVariableDecls(const lldb::VariableListSP &var_list_sp, 264 StreamString &stream, 265 const std::string &expr, 266 lldb::LanguageType wrapping_language) { 267 TokenVerifier tokens(expr); 268 269 for (size_t i = 0; i < var_list_sp->GetSize(); i++) { 270 lldb::VariableSP var_sp = var_list_sp->GetVariableAtIndex(i); 271 272 ConstString var_name = var_sp->GetName(); 273 274 275 // We can check for .block_descriptor w/o checking for langauge since this 276 // is not a valid identifier in either C or C++. 277 if (!var_name || var_name == ".block_descriptor") 278 continue; 279 280 if (!expr.empty() && !tokens.hasToken(var_name.GetStringRef())) 281 continue; 282 283 if ((var_name == "self" || var_name == "_cmd") && 284 (wrapping_language == lldb::eLanguageTypeObjC || 285 wrapping_language == lldb::eLanguageTypeObjC_plus_plus)) 286 continue; 287 288 if (var_name == "this" && 289 wrapping_language == lldb::eLanguageTypeC_plus_plus) 290 continue; 291 292 stream.Printf("using $__lldb_local_vars::%s;\n", var_name.AsCString()); 293 } 294 } 295 296 bool ClangExpressionSourceCode::GetText( 297 std::string &text, lldb::LanguageType wrapping_language, bool static_method, 298 ExecutionContext &exe_ctx, bool add_locals, bool force_add_all_locals, 299 llvm::ArrayRef<std::string> modules) const { 300 const char *target_specific_defines = "typedef signed char BOOL;\n"; 301 std::string module_macros; 302 303 Target *target = exe_ctx.GetTargetPtr(); 304 if (target) { 305 if (target->GetArchitecture().GetMachine() == llvm::Triple::aarch64 || 306 target->GetArchitecture().GetMachine() == llvm::Triple::aarch64_32) { 307 target_specific_defines = "typedef bool BOOL;\n"; 308 } 309 if (target->GetArchitecture().GetMachine() == llvm::Triple::x86_64) { 310 if (lldb::PlatformSP platform_sp = target->GetPlatform()) { 311 static ConstString g_platform_ios_simulator("ios-simulator"); 312 if (platform_sp->GetPluginName() == g_platform_ios_simulator) { 313 target_specific_defines = "typedef bool BOOL;\n"; 314 } 315 } 316 } 317 318 ClangModulesDeclVendor *decl_vendor = target->GetClangModulesDeclVendor(); 319 auto *persistent_vars = llvm::cast<ClangPersistentVariables>( 320 target->GetPersistentExpressionStateForLanguage(lldb::eLanguageTypeC)); 321 if (decl_vendor && persistent_vars) { 322 const ClangModulesDeclVendor::ModuleVector &hand_imported_modules = 323 persistent_vars->GetHandLoadedClangModules(); 324 ClangModulesDeclVendor::ModuleVector modules_for_macros; 325 326 for (ClangModulesDeclVendor::ModuleID module : hand_imported_modules) { 327 modules_for_macros.push_back(module); 328 } 329 330 if (target->GetEnableAutoImportClangModules()) { 331 if (StackFrame *frame = exe_ctx.GetFramePtr()) { 332 if (Block *block = frame->GetFrameBlock()) { 333 SymbolContext sc; 334 335 block->CalculateSymbolContext(&sc); 336 337 if (sc.comp_unit) { 338 StreamString error_stream; 339 340 decl_vendor->AddModulesForCompileUnit( 341 *sc.comp_unit, modules_for_macros, error_stream); 342 } 343 } 344 } 345 } 346 347 decl_vendor->ForEachMacro( 348 modules_for_macros, 349 [&module_macros](const std::string &expansion) -> bool { 350 module_macros.append(expansion); 351 module_macros.append("\n"); 352 return false; 353 }); 354 } 355 } 356 357 StreamString debug_macros_stream; 358 StreamString lldb_local_var_decls; 359 if (StackFrame *frame = exe_ctx.GetFramePtr()) { 360 const SymbolContext &sc = frame->GetSymbolContext( 361 lldb::eSymbolContextCompUnit | lldb::eSymbolContextLineEntry); 362 363 if (sc.comp_unit && sc.line_entry.IsValid()) { 364 DebugMacros *dm = sc.comp_unit->GetDebugMacros(); 365 if (dm) { 366 AddMacroState state(sc.line_entry.file, sc.line_entry.line); 367 AddMacros(dm, sc.comp_unit, state, debug_macros_stream); 368 } 369 } 370 371 if (add_locals) 372 if (target->GetInjectLocalVariables(&exe_ctx)) { 373 lldb::VariableListSP var_list_sp = 374 frame->GetInScopeVariableList(false, true); 375 AddLocalVariableDecls(var_list_sp, lldb_local_var_decls, 376 force_add_all_locals ? "" : m_body, 377 wrapping_language); 378 } 379 } 380 381 if (m_wrap) { 382 switch (wrapping_language) { 383 default: 384 return false; 385 case lldb::eLanguageTypeC: 386 case lldb::eLanguageTypeC_plus_plus: 387 case lldb::eLanguageTypeObjC: 388 break; 389 } 390 391 // Generate a list of @import statements that will import the specified 392 // module into our expression. 393 std::string module_imports; 394 for (const std::string &module : modules) { 395 module_imports.append("@import "); 396 module_imports.append(module); 397 module_imports.append(";\n"); 398 } 399 400 StreamString wrap_stream; 401 402 wrap_stream.Printf("%s\n%s\n%s\n%s\n%s\n", module_macros.c_str(), 403 debug_macros_stream.GetData(), g_expression_prefix, 404 target_specific_defines, m_prefix.c_str()); 405 406 // First construct a tagged form of the user expression so we can find it 407 // later: 408 std::string tagged_body; 409 switch (wrapping_language) { 410 default: 411 tagged_body = m_body; 412 break; 413 case lldb::eLanguageTypeC: 414 case lldb::eLanguageTypeC_plus_plus: 415 case lldb::eLanguageTypeObjC: 416 tagged_body.append(m_start_marker); 417 tagged_body.append(m_body); 418 tagged_body.append(m_end_marker); 419 break; 420 } 421 switch (wrapping_language) { 422 default: 423 break; 424 case lldb::eLanguageTypeC: 425 wrap_stream.Printf("%s" 426 "void \n" 427 "%s(void *$__lldb_arg) \n" 428 "{ \n" 429 " %s; \n" 430 "%s" 431 "} \n", 432 module_imports.c_str(), m_name.c_str(), 433 lldb_local_var_decls.GetData(), tagged_body.c_str()); 434 break; 435 case lldb::eLanguageTypeC_plus_plus: 436 wrap_stream.Printf("%s" 437 "void \n" 438 "$__lldb_class::%s(void *$__lldb_arg) \n" 439 "{ \n" 440 " %s; \n" 441 "%s" 442 "} \n", 443 module_imports.c_str(), m_name.c_str(), 444 lldb_local_var_decls.GetData(), tagged_body.c_str()); 445 break; 446 case lldb::eLanguageTypeObjC: 447 if (static_method) { 448 wrap_stream.Printf( 449 "%s" 450 "@interface $__lldb_objc_class ($__lldb_category) \n" 451 "+(void)%s:(void *)$__lldb_arg; \n" 452 "@end \n" 453 "@implementation $__lldb_objc_class ($__lldb_category) \n" 454 "+(void)%s:(void *)$__lldb_arg \n" 455 "{ \n" 456 " %s; \n" 457 "%s" 458 "} \n" 459 "@end \n", 460 module_imports.c_str(), m_name.c_str(), m_name.c_str(), 461 lldb_local_var_decls.GetData(), tagged_body.c_str()); 462 } else { 463 wrap_stream.Printf( 464 "%s" 465 "@interface $__lldb_objc_class ($__lldb_category) \n" 466 "-(void)%s:(void *)$__lldb_arg; \n" 467 "@end \n" 468 "@implementation $__lldb_objc_class ($__lldb_category) \n" 469 "-(void)%s:(void *)$__lldb_arg \n" 470 "{ \n" 471 " %s; \n" 472 "%s" 473 "} \n" 474 "@end \n", 475 module_imports.c_str(), m_name.c_str(), m_name.c_str(), 476 lldb_local_var_decls.GetData(), tagged_body.c_str()); 477 } 478 break; 479 } 480 481 text = wrap_stream.GetString(); 482 } else { 483 text.append(m_body); 484 } 485 486 return true; 487 } 488 489 bool ClangExpressionSourceCode::GetOriginalBodyBounds( 490 std::string transformed_text, lldb::LanguageType wrapping_language, 491 size_t &start_loc, size_t &end_loc) { 492 switch (wrapping_language) { 493 default: 494 return false; 495 case lldb::eLanguageTypeC: 496 case lldb::eLanguageTypeC_plus_plus: 497 case lldb::eLanguageTypeObjC: 498 break; 499 } 500 501 start_loc = transformed_text.find(m_start_marker); 502 if (start_loc == std::string::npos) 503 return false; 504 start_loc += m_start_marker.size(); 505 end_loc = transformed_text.find(m_end_marker); 506 return end_loc != std::string::npos; 507 } 508