1 //===-- CommandObjectRegister.cpp -----------------------------------------===// 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 "CommandObjectRegister.h" 10 #include "lldb/Core/Debugger.h" 11 #include "lldb/Core/DumpRegisterInfo.h" 12 #include "lldb/Core/DumpRegisterValue.h" 13 #include "lldb/Host/OptionParser.h" 14 #include "lldb/Interpreter/CommandInterpreter.h" 15 #include "lldb/Interpreter/CommandOptionArgumentTable.h" 16 #include "lldb/Interpreter/CommandReturnObject.h" 17 #include "lldb/Interpreter/OptionGroupFormat.h" 18 #include "lldb/Interpreter/OptionValueArray.h" 19 #include "lldb/Interpreter/OptionValueBoolean.h" 20 #include "lldb/Interpreter/OptionValueUInt64.h" 21 #include "lldb/Interpreter/Options.h" 22 #include "lldb/Target/ExecutionContext.h" 23 #include "lldb/Target/Process.h" 24 #include "lldb/Target/RegisterContext.h" 25 #include "lldb/Target/SectionLoadList.h" 26 #include "lldb/Target/Thread.h" 27 #include "lldb/Utility/Args.h" 28 #include "lldb/Utility/DataExtractor.h" 29 #include "lldb/Utility/RegisterValue.h" 30 #include "llvm/Support/Errno.h" 31 32 using namespace lldb; 33 using namespace lldb_private; 34 35 // "register read" 36 #define LLDB_OPTIONS_register_read 37 #include "CommandOptions.inc" 38 39 class CommandObjectRegisterRead : public CommandObjectParsed { 40 public: 41 CommandObjectRegisterRead(CommandInterpreter &interpreter) 42 : CommandObjectParsed( 43 interpreter, "register read", 44 "Dump the contents of one or more register values from the current " 45 "frame. If no register is specified, dumps them all.", 46 nullptr, 47 eCommandRequiresFrame | eCommandRequiresRegContext | 48 eCommandProcessMustBeLaunched | eCommandProcessMustBePaused), 49 m_format_options(eFormatDefault, UINT64_MAX, UINT64_MAX, 50 {{CommandArgumentType::eArgTypeFormat, 51 "Specify a format to be used for display. If this " 52 "is set, register fields will not be displayed."}}) { 53 CommandArgumentEntry arg; 54 CommandArgumentData register_arg; 55 56 // Define the first (and only) variant of this arg. 57 register_arg.arg_type = eArgTypeRegisterName; 58 register_arg.arg_repetition = eArgRepeatStar; 59 60 // There is only one variant this argument could be; put it into the 61 // argument entry. 62 arg.push_back(register_arg); 63 64 // Push the data for the first argument into the m_arguments vector. 65 m_arguments.push_back(arg); 66 67 // Add the "--format" 68 m_option_group.Append(&m_format_options, 69 OptionGroupFormat::OPTION_GROUP_FORMAT | 70 OptionGroupFormat::OPTION_GROUP_GDB_FMT, 71 LLDB_OPT_SET_ALL); 72 m_option_group.Append(&m_command_options); 73 m_option_group.Finalize(); 74 } 75 76 ~CommandObjectRegisterRead() override = default; 77 78 void 79 HandleArgumentCompletion(CompletionRequest &request, 80 OptionElementVector &opt_element_vector) override { 81 if (!m_exe_ctx.HasProcessScope()) 82 return; 83 84 lldb_private::CommandCompletions::InvokeCommonCompletionCallbacks( 85 GetCommandInterpreter(), lldb::eRegisterCompletion, request, nullptr); 86 } 87 88 Options *GetOptions() override { return &m_option_group; } 89 90 bool DumpRegister(const ExecutionContext &exe_ctx, Stream &strm, 91 RegisterContext ®_ctx, const RegisterInfo ®_info, 92 bool print_flags) { 93 RegisterValue reg_value; 94 if (!reg_ctx.ReadRegister(®_info, reg_value)) 95 return false; 96 97 strm.Indent(); 98 99 bool prefix_with_altname = (bool)m_command_options.alternate_name; 100 bool prefix_with_name = !prefix_with_altname; 101 DumpRegisterValue(reg_value, strm, reg_info, prefix_with_name, 102 prefix_with_altname, m_format_options.GetFormat(), 8, 103 exe_ctx.GetBestExecutionContextScope(), print_flags, 104 exe_ctx.GetTargetSP()); 105 if ((reg_info.encoding == eEncodingUint) || 106 (reg_info.encoding == eEncodingSint)) { 107 Process *process = exe_ctx.GetProcessPtr(); 108 if (process && reg_info.byte_size == process->GetAddressByteSize()) { 109 addr_t reg_addr = reg_value.GetAsUInt64(LLDB_INVALID_ADDRESS); 110 if (reg_addr != LLDB_INVALID_ADDRESS) { 111 Address so_reg_addr; 112 if (exe_ctx.GetTargetRef().GetSectionLoadList().ResolveLoadAddress( 113 reg_addr, so_reg_addr)) { 114 strm.PutCString(" "); 115 so_reg_addr.Dump(&strm, exe_ctx.GetBestExecutionContextScope(), 116 Address::DumpStyleResolvedDescription); 117 } 118 } 119 } 120 } 121 strm.EOL(); 122 return true; 123 } 124 125 bool DumpRegisterSet(const ExecutionContext &exe_ctx, Stream &strm, 126 RegisterContext *reg_ctx, size_t set_idx, 127 bool primitive_only = false) { 128 uint32_t unavailable_count = 0; 129 uint32_t available_count = 0; 130 131 if (!reg_ctx) 132 return false; // thread has no registers (i.e. core files are corrupt, 133 // incomplete crash logs...) 134 135 const RegisterSet *const reg_set = reg_ctx->GetRegisterSet(set_idx); 136 if (reg_set) { 137 strm.Printf("%s:\n", (reg_set->name ? reg_set->name : "unknown")); 138 strm.IndentMore(); 139 const size_t num_registers = reg_set->num_registers; 140 for (size_t reg_idx = 0; reg_idx < num_registers; ++reg_idx) { 141 const uint32_t reg = reg_set->registers[reg_idx]; 142 const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoAtIndex(reg); 143 // Skip the dumping of derived register if primitive_only is true. 144 if (primitive_only && reg_info && reg_info->value_regs) 145 continue; 146 147 if (reg_info && DumpRegister(exe_ctx, strm, *reg_ctx, *reg_info, 148 /*print_flags=*/false)) 149 ++available_count; 150 else 151 ++unavailable_count; 152 } 153 strm.IndentLess(); 154 if (unavailable_count) { 155 strm.Indent(); 156 strm.Printf("%u registers were unavailable.\n", unavailable_count); 157 } 158 strm.EOL(); 159 } 160 return available_count > 0; 161 } 162 163 protected: 164 void DoExecute(Args &command, CommandReturnObject &result) override { 165 Stream &strm = result.GetOutputStream(); 166 RegisterContext *reg_ctx = m_exe_ctx.GetRegisterContext(); 167 168 if (command.GetArgumentCount() == 0) { 169 size_t set_idx; 170 171 size_t num_register_sets = 1; 172 const size_t set_array_size = m_command_options.set_indexes.GetSize(); 173 if (set_array_size > 0) { 174 for (size_t i = 0; i < set_array_size; ++i) { 175 set_idx = 176 m_command_options.set_indexes[i]->GetValueAs<uint64_t>().value_or( 177 UINT32_MAX); 178 if (set_idx < reg_ctx->GetRegisterSetCount()) { 179 if (!DumpRegisterSet(m_exe_ctx, strm, reg_ctx, set_idx)) { 180 if (errno) 181 result.AppendErrorWithFormatv("register read failed: {0}\n", 182 llvm::sys::StrError()); 183 else 184 result.AppendError("unknown error while reading registers.\n"); 185 break; 186 } 187 } else { 188 result.AppendErrorWithFormat( 189 "invalid register set index: %" PRIu64 "\n", (uint64_t)set_idx); 190 break; 191 } 192 } 193 } else { 194 if (m_command_options.dump_all_sets) 195 num_register_sets = reg_ctx->GetRegisterSetCount(); 196 197 for (set_idx = 0; set_idx < num_register_sets; ++set_idx) { 198 // When dump_all_sets option is set, dump primitive as well as 199 // derived registers. 200 DumpRegisterSet(m_exe_ctx, strm, reg_ctx, set_idx, 201 !m_command_options.dump_all_sets.GetCurrentValue()); 202 } 203 } 204 } else { 205 if (m_command_options.dump_all_sets) { 206 result.AppendError("the --all option can't be used when registers " 207 "names are supplied as arguments\n"); 208 } else if (m_command_options.set_indexes.GetSize() > 0) { 209 result.AppendError("the --set <set> option can't be used when " 210 "registers names are supplied as arguments\n"); 211 } else { 212 for (auto &entry : command) { 213 // in most LLDB commands we accept $rbx as the name for register RBX 214 // - and here we would reject it and non-existant. we should be more 215 // consistent towards the user and allow them to say reg read $rbx - 216 // internally, however, we should be strict and not allow ourselves 217 // to call our registers $rbx in our own API 218 auto arg_str = entry.ref(); 219 arg_str.consume_front("$"); 220 221 if (const RegisterInfo *reg_info = 222 reg_ctx->GetRegisterInfoByName(arg_str)) { 223 // If they have asked for a specific format don't obscure that by 224 // printing flags afterwards. 225 bool print_flags = 226 !m_format_options.GetFormatValue().OptionWasSet(); 227 if (!DumpRegister(m_exe_ctx, strm, *reg_ctx, *reg_info, 228 print_flags)) 229 strm.Printf("%-12s = error: unavailable\n", reg_info->name); 230 } else { 231 result.AppendErrorWithFormat("Invalid register name '%s'.\n", 232 arg_str.str().c_str()); 233 } 234 } 235 } 236 } 237 } 238 239 class CommandOptions : public OptionGroup { 240 public: 241 CommandOptions() 242 : set_indexes(OptionValue::ConvertTypeToMask(OptionValue::eTypeUInt64)), 243 dump_all_sets(false, false), // Initial and default values are false 244 alternate_name(false, false) {} 245 246 ~CommandOptions() override = default; 247 248 llvm::ArrayRef<OptionDefinition> GetDefinitions() override { 249 return llvm::ArrayRef(g_register_read_options); 250 } 251 252 void OptionParsingStarting(ExecutionContext *execution_context) override { 253 set_indexes.Clear(); 254 dump_all_sets.Clear(); 255 alternate_name.Clear(); 256 } 257 258 Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_value, 259 ExecutionContext *execution_context) override { 260 Status error; 261 const int short_option = GetDefinitions()[option_idx].short_option; 262 switch (short_option) { 263 case 's': { 264 OptionValueSP value_sp(OptionValueUInt64::Create(option_value, error)); 265 if (value_sp) 266 set_indexes.AppendValue(value_sp); 267 } break; 268 269 case 'a': 270 // When we don't use OptionValue::SetValueFromCString(const char *) to 271 // set an option value, it won't be marked as being set in the options 272 // so we make a call to let users know the value was set via option 273 dump_all_sets.SetCurrentValue(true); 274 dump_all_sets.SetOptionWasSet(); 275 break; 276 277 case 'A': 278 // When we don't use OptionValue::SetValueFromCString(const char *) to 279 // set an option value, it won't be marked as being set in the options 280 // so we make a call to let users know the value was set via option 281 alternate_name.SetCurrentValue(true); 282 dump_all_sets.SetOptionWasSet(); 283 break; 284 285 default: 286 llvm_unreachable("Unimplemented option"); 287 } 288 return error; 289 } 290 291 // Instance variables to hold the values for command options. 292 OptionValueArray set_indexes; 293 OptionValueBoolean dump_all_sets; 294 OptionValueBoolean alternate_name; 295 }; 296 297 OptionGroupOptions m_option_group; 298 OptionGroupFormat m_format_options; 299 CommandOptions m_command_options; 300 }; 301 302 // "register write" 303 class CommandObjectRegisterWrite : public CommandObjectParsed { 304 public: 305 CommandObjectRegisterWrite(CommandInterpreter &interpreter) 306 : CommandObjectParsed(interpreter, "register write", 307 "Modify a single register value.", nullptr, 308 eCommandRequiresFrame | eCommandRequiresRegContext | 309 eCommandProcessMustBeLaunched | 310 eCommandProcessMustBePaused) { 311 CommandArgumentEntry arg1; 312 CommandArgumentEntry arg2; 313 CommandArgumentData register_arg; 314 CommandArgumentData value_arg; 315 316 // Define the first (and only) variant of this arg. 317 register_arg.arg_type = eArgTypeRegisterName; 318 register_arg.arg_repetition = eArgRepeatPlain; 319 320 // There is only one variant this argument could be; put it into the 321 // argument entry. 322 arg1.push_back(register_arg); 323 324 // Define the first (and only) variant of this arg. 325 value_arg.arg_type = eArgTypeValue; 326 value_arg.arg_repetition = eArgRepeatPlain; 327 328 // There is only one variant this argument could be; put it into the 329 // argument entry. 330 arg2.push_back(value_arg); 331 332 // Push the data for the first argument into the m_arguments vector. 333 m_arguments.push_back(arg1); 334 m_arguments.push_back(arg2); 335 } 336 337 ~CommandObjectRegisterWrite() override = default; 338 339 void 340 HandleArgumentCompletion(CompletionRequest &request, 341 OptionElementVector &opt_element_vector) override { 342 if (!m_exe_ctx.HasProcessScope() || request.GetCursorIndex() != 0) 343 return; 344 345 lldb_private::CommandCompletions::InvokeCommonCompletionCallbacks( 346 GetCommandInterpreter(), lldb::eRegisterCompletion, request, nullptr); 347 } 348 349 protected: 350 void DoExecute(Args &command, CommandReturnObject &result) override { 351 DataExtractor reg_data; 352 RegisterContext *reg_ctx = m_exe_ctx.GetRegisterContext(); 353 354 if (command.GetArgumentCount() != 2) { 355 result.AppendError( 356 "register write takes exactly 2 arguments: <reg-name> <value>"); 357 } else { 358 auto reg_name = command[0].ref(); 359 auto value_str = command[1].ref(); 360 361 // in most LLDB commands we accept $rbx as the name for register RBX - 362 // and here we would reject it and non-existant. we should be more 363 // consistent towards the user and allow them to say reg write $rbx - 364 // internally, however, we should be strict and not allow ourselves to 365 // call our registers $rbx in our own API 366 reg_name.consume_front("$"); 367 368 const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoByName(reg_name); 369 370 if (reg_info) { 371 RegisterValue reg_value; 372 373 Status error(reg_value.SetValueFromString(reg_info, value_str)); 374 if (error.Success()) { 375 if (reg_ctx->WriteRegister(reg_info, reg_value)) { 376 // Toss all frames and anything else in the thread after a register 377 // has been written. 378 m_exe_ctx.GetThreadRef().Flush(); 379 result.SetStatus(eReturnStatusSuccessFinishNoResult); 380 return; 381 } 382 } 383 if (error.AsCString()) { 384 result.AppendErrorWithFormat( 385 "Failed to write register '%s' with value '%s': %s\n", 386 reg_name.str().c_str(), value_str.str().c_str(), 387 error.AsCString()); 388 } else { 389 result.AppendErrorWithFormat( 390 "Failed to write register '%s' with value '%s'", 391 reg_name.str().c_str(), value_str.str().c_str()); 392 } 393 } else { 394 result.AppendErrorWithFormat("Register not found for '%s'.\n", 395 reg_name.str().c_str()); 396 } 397 } 398 } 399 }; 400 401 // "register info" 402 class CommandObjectRegisterInfo : public CommandObjectParsed { 403 public: 404 CommandObjectRegisterInfo(CommandInterpreter &interpreter) 405 : CommandObjectParsed(interpreter, "register info", 406 "View information about a register.", nullptr, 407 eCommandRequiresFrame | eCommandRequiresRegContext | 408 eCommandProcessMustBeLaunched | 409 eCommandProcessMustBePaused) { 410 SetHelpLong(R"( 411 Name The name lldb uses for the register, optionally with an alias. 412 Size The size of the register in bytes and again in bits. 413 Invalidates (*) The registers that would be changed if you wrote this 414 register. For example, writing to a narrower alias of a wider 415 register would change the value of the wider register. 416 Read from (*) The registers that the value of this register is constructed 417 from. For example, a narrower alias of a wider register will be 418 read from the wider register. 419 In sets (*) The register sets that contain this register. For example the 420 PC will be in the "General Purpose Register" set. 421 Fields (*) A table of the names and bit positions of the values contained 422 in this register. 423 424 Fields marked with (*) may not always be present. Some information may be 425 different for the same register when connected to different debug servers.)"); 426 427 CommandArgumentData register_arg; 428 register_arg.arg_type = eArgTypeRegisterName; 429 register_arg.arg_repetition = eArgRepeatPlain; 430 431 CommandArgumentEntry arg1; 432 arg1.push_back(register_arg); 433 m_arguments.push_back(arg1); 434 } 435 436 ~CommandObjectRegisterInfo() override = default; 437 438 void 439 HandleArgumentCompletion(CompletionRequest &request, 440 OptionElementVector &opt_element_vector) override { 441 if (!m_exe_ctx.HasProcessScope() || request.GetCursorIndex() != 0) 442 return; 443 CommandCompletions::InvokeCommonCompletionCallbacks( 444 GetCommandInterpreter(), lldb::eRegisterCompletion, request, nullptr); 445 } 446 447 protected: 448 void DoExecute(Args &command, CommandReturnObject &result) override { 449 if (command.GetArgumentCount() != 1) { 450 result.AppendError("register info takes exactly 1 argument: <reg-name>"); 451 return; 452 } 453 454 llvm::StringRef reg_name = command[0].ref(); 455 RegisterContext *reg_ctx = m_exe_ctx.GetRegisterContext(); 456 const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoByName(reg_name); 457 if (reg_info) { 458 DumpRegisterInfo( 459 result.GetOutputStream(), *reg_ctx, *reg_info, 460 GetCommandInterpreter().GetDebugger().GetTerminalWidth()); 461 result.SetStatus(eReturnStatusSuccessFinishResult); 462 } else 463 result.AppendErrorWithFormat("No register found with name '%s'.\n", 464 reg_name.str().c_str()); 465 } 466 }; 467 468 // CommandObjectRegister constructor 469 CommandObjectRegister::CommandObjectRegister(CommandInterpreter &interpreter) 470 : CommandObjectMultiword(interpreter, "register", 471 "Commands to access registers for the current " 472 "thread and stack frame.", 473 "register [read|write|info] ...") { 474 LoadSubCommand("read", 475 CommandObjectSP(new CommandObjectRegisterRead(interpreter))); 476 LoadSubCommand("write", 477 CommandObjectSP(new CommandObjectRegisterWrite(interpreter))); 478 LoadSubCommand("info", 479 CommandObjectSP(new CommandObjectRegisterInfo(interpreter))); 480 } 481 482 CommandObjectRegister::~CommandObjectRegister() = default; 483