1 //===-- CommandObjectExpression.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 "CommandObjectExpression.h" 11 12 // C Includes 13 // C++ Includes 14 // Other libraries and framework includes 15 // Project includes 16 #include "lldb/Interpreter/Args.h" 17 #include "lldb/Core/Value.h" 18 #include "lldb/Core/InputReader.h" 19 #include "lldb/Expression/ClangExpression.h" 20 #include "lldb/Expression/ClangExpressionDeclMap.h" 21 #include "lldb/Expression/ClangExpressionVariable.h" 22 #include "lldb/Expression/DWARFExpression.h" 23 #include "lldb/Host/Host.h" 24 #include "lldb/Core/Debugger.h" 25 #include "lldb/Interpreter/CommandInterpreter.h" 26 #include "lldb/Interpreter/CommandReturnObject.h" 27 #include "lldb/Symbol/ObjectFile.h" 28 #include "lldb/Symbol/Variable.h" 29 #include "lldb/Target/Process.h" 30 #include "lldb/Target/StackFrame.h" 31 #include "lldb/Target/Target.h" 32 #include "llvm/ADT/StringRef.h" 33 34 using namespace lldb; 35 using namespace lldb_private; 36 37 CommandObjectExpression::CommandOptions::CommandOptions () : 38 Options() 39 { 40 // Keep only one place to reset the values to their defaults 41 ResetOptionValues(); 42 } 43 44 45 CommandObjectExpression::CommandOptions::~CommandOptions () 46 { 47 } 48 49 Error 50 CommandObjectExpression::CommandOptions::SetOptionValue (int option_idx, const char *option_arg) 51 { 52 Error error; 53 54 char short_option = (char) m_getopt_table[option_idx].val; 55 56 switch (short_option) 57 { 58 case 'l': 59 if (language.SetLanguageFromCString (option_arg) == false) 60 { 61 error.SetErrorStringWithFormat("Invalid language option argument '%s'.\n", option_arg); 62 } 63 break; 64 65 case 'g': 66 debug = true; 67 break; 68 69 case 'f': 70 error = Args::StringToFormat(option_arg, format); 71 break; 72 73 case 'i': 74 use_ir = true; 75 break; 76 77 default: 78 error.SetErrorStringWithFormat("Invalid short option character '%c'.\n", short_option); 79 break; 80 } 81 82 return error; 83 } 84 85 void 86 CommandObjectExpression::CommandOptions::ResetOptionValues () 87 { 88 Options::ResetOptionValues(); 89 language.Clear(); 90 debug = false; 91 format = eFormatDefault; 92 show_types = true; 93 show_summary = true; 94 use_ir = false; 95 } 96 97 const lldb::OptionDefinition* 98 CommandObjectExpression::CommandOptions::GetDefinitions () 99 { 100 return g_option_table; 101 } 102 103 CommandObjectExpression::CommandObjectExpression () : 104 CommandObject ( 105 "expression", 106 "Evaluate a C expression in the current program context, using variables currently in scope.", 107 "expression [<cmd-options>] <expr>"), 108 m_expr_line_count (0), 109 m_expr_lines () 110 { 111 SetHelpLong( 112 "Examples: \n\ 113 \n\ 114 expr my_struct->a = my_array[3] \n\ 115 expr -f bin -- (index * 8) + 5 \n\ 116 expr char c[] = \"foo\"; c[0]\n"); 117 } 118 119 CommandObjectExpression::~CommandObjectExpression () 120 { 121 } 122 123 Options * 124 CommandObjectExpression::GetOptions () 125 { 126 return &m_options; 127 } 128 129 130 bool 131 CommandObjectExpression::Execute 132 ( 133 CommandInterpreter &interpreter, 134 Args& command, 135 CommandReturnObject &result 136 ) 137 { 138 return false; 139 } 140 141 142 size_t 143 CommandObjectExpression::MultiLineExpressionCallback 144 ( 145 void *baton, 146 InputReader &reader, 147 lldb::InputReaderAction notification, 148 const char *bytes, 149 size_t bytes_len 150 ) 151 { 152 CommandObjectExpression *cmd_object_expr = (CommandObjectExpression *) baton; 153 154 switch (notification) 155 { 156 case eInputReaderActivate: 157 reader.GetDebugger().GetOutputStream().Printf("%s\n", "Enter expressions, then terminate with an empty line to evaluate:"); 158 // Fall through 159 case eInputReaderReactivate: 160 //if (out_fh) 161 // reader.GetDebugger().GetOutputStream().Printf ("%3u: ", cmd_object_expr->m_expr_line_count); 162 break; 163 164 case eInputReaderDeactivate: 165 break; 166 167 case eInputReaderGotToken: 168 ++cmd_object_expr->m_expr_line_count; 169 if (bytes && bytes_len) 170 { 171 cmd_object_expr->m_expr_lines.append (bytes, bytes_len + 1); 172 } 173 174 if (bytes_len == 0) 175 reader.SetIsDone(true); 176 //else if (out_fh && !reader->IsDone()) 177 // ::fprintf (out_fh, "%3u: ", cmd_object_expr->m_expr_line_count); 178 break; 179 180 case eInputReaderDone: 181 { 182 bool bare = false; 183 cmd_object_expr->EvaluateExpression (cmd_object_expr->m_expr_lines.c_str(), 184 bare, 185 reader.GetDebugger().GetOutputStream(), 186 reader.GetDebugger().GetErrorStream()); 187 } 188 break; 189 } 190 191 return bytes_len; 192 } 193 194 bool 195 CommandObjectExpression::EvaluateExpression (const char *expr, bool bare, Stream &output_stream, Stream &error_stream) 196 { 197 Log *log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS); 198 199 //////////////////////////////////// 200 // Set up the target and compiler 201 // 202 203 Target *target = m_exe_ctx.target; 204 205 if (!target) 206 { 207 error_stream.PutCString ("error: invalid target\n"); 208 return false; 209 } 210 211 ConstString target_triple; 212 213 target->GetTargetTriple (target_triple); 214 215 if (!target_triple) 216 target_triple = Host::GetTargetTriple (); 217 218 if (!target_triple) 219 { 220 error_stream.PutCString ("error: invalid target triple\n"); 221 return false; 222 } 223 224 ClangExpressionDeclMap expr_decl_map (&m_exe_ctx); 225 ClangExpression clang_expr (target_triple.AsCString (), &expr_decl_map); 226 227 ////////////////////////// 228 // Parse the expression 229 // 230 231 unsigned num_errors; 232 233 if (bare) 234 num_errors = clang_expr.ParseBareExpression (llvm::StringRef (expr), error_stream); 235 else 236 num_errors = clang_expr.ParseExpression (expr, error_stream, m_options.use_ir); 237 238 if (num_errors) 239 { 240 error_stream.Printf ("error: %d errors parsing expression\n", num_errors); 241 return false; 242 } 243 244 /////////////////////////////////////////////// 245 // Convert the output of the parser to DWARF 246 // 247 248 StreamString dwarf_opcodes; 249 dwarf_opcodes.SetByteOrder (eByteOrderHost); 250 dwarf_opcodes.GetFlags ().Set (Stream::eBinary); 251 252 ClangExpressionVariableList expr_local_vars; 253 254 bool success; 255 bool canInterpret = false; 256 257 if (m_options.use_ir) 258 { 259 canInterpret = clang_expr.ConvertIRToDWARF (expr_local_vars, dwarf_opcodes); 260 261 if (canInterpret) 262 { 263 if (log) 264 log->Printf("Code can be interpreted."); 265 success = true; 266 } 267 else 268 { 269 if (log) 270 log->Printf("Code cannot be interpreted and must be run in the target."); 271 success = clang_expr.PrepareIRForTarget (expr_local_vars); 272 } 273 274 if (!success) 275 { 276 error_stream.PutCString ("error: expression couldn't be converted to IR\n"); 277 return false; 278 } 279 280 if (canInterpret) 281 { 282 // TODO interpret IR 283 return false; 284 } 285 else 286 { 287 if (!clang_expr.JITFunction (m_exe_ctx, "___clang_expr")) 288 { 289 error_stream.PutCString ("error: IR could not be JIT compiled\n"); 290 return false; 291 } 292 293 if (!clang_expr.WriteJITCode (m_exe_ctx)) 294 { 295 error_stream.PutCString ("error: JIT code could not be written to the target\n"); 296 return false; 297 } 298 299 lldb::addr_t function_address(clang_expr.GetFunctionAddress ("___clang_expr")); 300 301 if (function_address == LLDB_INVALID_ADDRESS) 302 { 303 error_stream.PutCString ("JIT compiled code's address couldn't be found\n"); 304 return false; 305 } 306 307 log->Printf("Function is at 0x%llx", (uint64_t)function_address); 308 } 309 } 310 else 311 { 312 success = (clang_expr.ConvertExpressionToDWARF (expr_local_vars, dwarf_opcodes) == 0); 313 314 if (!success) 315 { 316 error_stream.PutCString ("error: expression couldn't be translated to DWARF\n"); 317 return false; 318 } 319 320 ////////////////////////////////////////// 321 // Evaluate the generated DWARF opcodes 322 // 323 324 DataExtractor dwarf_opcodes_data (dwarf_opcodes.GetData (), dwarf_opcodes.GetSize (), eByteOrderHost, 8); 325 DWARFExpression dwarf_expr (dwarf_opcodes_data, 0, dwarf_opcodes_data.GetByteSize (), NULL); 326 327 dwarf_expr.SetExpressionLocalVariableList(&expr_local_vars); 328 329 if (log) 330 { 331 StreamString stream_string; 332 333 log->PutCString ("Expression parsed ok, dwarf opcodes:"); 334 335 stream_string.PutCString ("\n"); 336 stream_string.IndentMore (); 337 dwarf_expr.GetDescription (&stream_string, lldb::eDescriptionLevelVerbose); 338 stream_string.IndentLess (); 339 stream_string.EOL (); 340 341 log->PutCString (stream_string.GetString ().c_str ()); 342 } 343 344 clang::ASTContext *ast_context = clang_expr.GetASTContext (); 345 Value expr_result; 346 Error expr_error; 347 success = dwarf_expr.Evaluate (&m_exe_ctx, ast_context, NULL, expr_result, &expr_error); 348 349 if (!success) 350 { 351 error_stream.Printf ("error: couldn't evaluate DWARF expression: %s\n", expr_error.AsCString ()); 352 return false; 353 } 354 355 /////////////////////////////////////// 356 // Interpret the result and print it 357 // 358 359 lldb::Format format = m_options.format; 360 361 // Resolve any values that are possible 362 expr_result.ResolveValue (&m_exe_ctx, ast_context); 363 364 if (expr_result.GetContextType () == Value::eContextTypeInvalid && 365 expr_result.GetValueType () == Value::eValueTypeScalar && 366 format == eFormatDefault) 367 { 368 // The expression result is just a scalar with no special formatting 369 expr_result.GetScalar ().GetValue (&output_stream, m_options.show_types); 370 output_stream.EOL (); 371 return true; 372 } 373 374 // The expression result is more complext and requires special handling 375 DataExtractor data; 376 expr_error = expr_result.GetValueAsData (&m_exe_ctx, ast_context, data, 0); 377 378 if (!expr_error.Success ()) 379 { 380 error_stream.Printf ("error: couldn't resolve result value: %s\n", expr_error.AsCString ()); 381 return false; 382 } 383 384 if (format == eFormatDefault) 385 format = expr_result.GetValueDefaultFormat (); 386 387 void *clang_type = expr_result.GetValueOpaqueClangQualType (); 388 389 if (clang_type) 390 { 391 if (m_options.show_types) 392 Type::DumpClangTypeName (&output_stream, clang_type); 393 394 Type::DumpValue (&m_exe_ctx, // The execution context for memory and variable access 395 ast_context, // The ASTContext that the clang type belongs to 396 clang_type, // The opaque clang type we want to dump that value of 397 &output_stream, // Stream to dump to 398 format, // Format to use when dumping 399 data, // A buffer containing the bytes for the clang type 400 0, // Byte offset within "data" where value is 401 data.GetByteSize (), // Size in bytes of the value we are dumping 402 0, // Bitfield bit size 403 0, // Bitfield bit offset 404 m_options.show_types, // Show types? 405 m_options.show_summary, // Show summary? 406 m_options.debug, // Debug logging output? 407 UINT32_MAX); // Depth to dump in case this is an aggregate type 408 } 409 else 410 { 411 data.Dump (&output_stream, // Stream to dump to 412 0, // Byte offset within "data" 413 format, // Format to use when dumping 414 data.GetByteSize (), // Size in bytes of each item we are dumping 415 1, // Number of items to dump 416 UINT32_MAX, // Number of items per line 417 LLDB_INVALID_ADDRESS, // Invalid address, don't show any offset/address context 418 0, // Bitfield bit size 419 0); // Bitfield bit offset 420 } 421 output_stream.EOL(); 422 423 return true; 424 } 425 } 426 427 bool 428 CommandObjectExpression::ExecuteRawCommandString 429 ( 430 CommandInterpreter &interpreter, 431 const char *command, 432 CommandReturnObject &result 433 ) 434 { 435 m_exe_ctx = interpreter.GetDebugger().GetExecutionContext(); 436 437 m_options.ResetOptionValues(); 438 439 const char * expr = NULL; 440 441 if (command[0] == '\0') 442 { 443 m_expr_lines.clear(); 444 m_expr_line_count = 0; 445 446 InputReaderSP reader_sp (new InputReader(interpreter.GetDebugger())); 447 if (reader_sp) 448 { 449 Error err (reader_sp->Initialize (CommandObjectExpression::MultiLineExpressionCallback, 450 this, // baton 451 eInputReaderGranularityLine, // token size, to pass to callback function 452 NULL, // end token 453 NULL, // prompt 454 true)); // echo input 455 if (err.Success()) 456 { 457 interpreter.GetDebugger().PushInputReader (reader_sp); 458 result.SetStatus (eReturnStatusSuccessFinishNoResult); 459 } 460 else 461 { 462 result.AppendError (err.AsCString()); 463 result.SetStatus (eReturnStatusFailed); 464 } 465 } 466 else 467 { 468 result.AppendError("out of memory"); 469 result.SetStatus (eReturnStatusFailed); 470 } 471 return result.Succeeded(); 472 } 473 474 if (command[0] == '-') 475 { 476 // We have some options and these options MUST end with --. 477 const char *end_options = NULL; 478 const char *s = command; 479 while (s && s[0]) 480 { 481 end_options = ::strstr (s, "--"); 482 if (end_options) 483 { 484 end_options += 2; // Get past the "--" 485 if (::isspace (end_options[0])) 486 { 487 expr = end_options; 488 while (::isspace (*expr)) 489 ++expr; 490 break; 491 } 492 } 493 s = end_options; 494 } 495 496 if (end_options) 497 { 498 Args args (command, end_options - command); 499 if (!ParseOptions (interpreter, args, result)) 500 return false; 501 } 502 } 503 504 if (expr == NULL) 505 expr = command; 506 507 return EvaluateExpression (expr, false, result.GetOutputStream(), result.GetErrorStream()); 508 } 509 510 lldb::OptionDefinition 511 CommandObjectExpression::CommandOptions::g_option_table[] = 512 { 513 { LLDB_OPT_SET_ALL, false, "language", 'l', required_argument, NULL, 0, "[c|c++|objc|objc++]", "Sets the language to use when parsing the expression."}, 514 { LLDB_OPT_SET_ALL, false, "format", 'f', required_argument, NULL, 0, "[ [bool|b] | [bin] | [char|c] | [oct|o] | [dec|i|d|u] | [hex|x] | [float|f] | [cstr|s] ]", "Specify the format that the expression output should use."}, 515 { LLDB_OPT_SET_ALL, false, "debug", 'g', no_argument, NULL, 0, NULL, "Enable verbose debug logging of the expression parsing and evaluation."}, 516 { LLDB_OPT_SET_ALL, false, "use-ir", 'i', no_argument, NULL, 0, NULL, "[Temporary] Instructs the expression evaluator to use IR instead of ASTs."}, 517 { 0, false, NULL, 0, 0, NULL, NULL, NULL, NULL } 518 }; 519 520