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/DumpRegisterValue.h" 12 #include "lldb/Host/OptionParser.h" 13 #include "lldb/Interpreter/CommandReturnObject.h" 14 #include "lldb/Interpreter/OptionGroupFormat.h" 15 #include "lldb/Interpreter/OptionValueArray.h" 16 #include "lldb/Interpreter/OptionValueBoolean.h" 17 #include "lldb/Interpreter/OptionValueUInt64.h" 18 #include "lldb/Interpreter/Options.h" 19 #include "lldb/Target/ExecutionContext.h" 20 #include "lldb/Target/Process.h" 21 #include "lldb/Target/RegisterContext.h" 22 #include "lldb/Target/SectionLoadList.h" 23 #include "lldb/Target/Thread.h" 24 #include "lldb/Utility/Args.h" 25 #include "lldb/Utility/DataExtractor.h" 26 #include "lldb/Utility/RegisterValue.h" 27 #include "llvm/Support/Errno.h" 28 29 using namespace lldb; 30 using namespace lldb_private; 31 32 // "register read" 33 #define LLDB_OPTIONS_register_read 34 #include "CommandOptions.inc" 35 36 class CommandObjectRegisterRead : public CommandObjectParsed { 37 public: 38 CommandObjectRegisterRead(CommandInterpreter &interpreter) 39 : CommandObjectParsed( 40 interpreter, "register read", 41 "Dump the contents of one or more register values from the current " 42 "frame. If no register is specified, dumps them all.", 43 nullptr, 44 eCommandRequiresFrame | eCommandRequiresRegContext | 45 eCommandProcessMustBeLaunched | eCommandProcessMustBePaused), 46 m_option_group(), m_format_options(eFormatDefault), 47 m_command_options() { 48 CommandArgumentEntry arg; 49 CommandArgumentData register_arg; 50 51 // Define the first (and only) variant of this arg. 52 register_arg.arg_type = eArgTypeRegisterName; 53 register_arg.arg_repetition = eArgRepeatStar; 54 55 // There is only one variant this argument could be; put it into the 56 // argument entry. 57 arg.push_back(register_arg); 58 59 // Push the data for the first argument into the m_arguments vector. 60 m_arguments.push_back(arg); 61 62 // Add the "--format" 63 m_option_group.Append(&m_format_options, 64 OptionGroupFormat::OPTION_GROUP_FORMAT | 65 OptionGroupFormat::OPTION_GROUP_GDB_FMT, 66 LLDB_OPT_SET_ALL); 67 m_option_group.Append(&m_command_options); 68 m_option_group.Finalize(); 69 } 70 71 ~CommandObjectRegisterRead() override = default; 72 73 void 74 HandleArgumentCompletion(CompletionRequest &request, 75 OptionElementVector &opt_element_vector) override { 76 if (!m_exe_ctx.HasProcessScope()) 77 return; 78 79 CommandCompletions::InvokeCommonCompletionCallbacks( 80 GetCommandInterpreter(), CommandCompletions::eRegisterCompletion, 81 request, nullptr); 82 } 83 84 Options *GetOptions() override { return &m_option_group; } 85 86 bool DumpRegister(const ExecutionContext &exe_ctx, Stream &strm, 87 RegisterContext *reg_ctx, const RegisterInfo *reg_info) { 88 if (reg_info) { 89 RegisterValue reg_value; 90 91 if (reg_ctx->ReadRegister(reg_info, reg_value)) { 92 strm.Indent(); 93 94 bool prefix_with_altname = (bool)m_command_options.alternate_name; 95 bool prefix_with_name = !prefix_with_altname; 96 DumpRegisterValue(reg_value, &strm, reg_info, prefix_with_name, 97 prefix_with_altname, m_format_options.GetFormat(), 8); 98 if ((reg_info->encoding == eEncodingUint) || 99 (reg_info->encoding == eEncodingSint)) { 100 Process *process = exe_ctx.GetProcessPtr(); 101 if (process && reg_info->byte_size == process->GetAddressByteSize()) { 102 addr_t reg_addr = reg_value.GetAsUInt64(LLDB_INVALID_ADDRESS); 103 if (reg_addr != LLDB_INVALID_ADDRESS) { 104 Address so_reg_addr; 105 if (exe_ctx.GetTargetRef() 106 .GetSectionLoadList() 107 .ResolveLoadAddress(reg_addr, so_reg_addr)) { 108 strm.PutCString(" "); 109 so_reg_addr.Dump(&strm, exe_ctx.GetBestExecutionContextScope(), 110 Address::DumpStyleResolvedDescription); 111 } 112 } 113 } 114 } 115 strm.EOL(); 116 return true; 117 } 118 } 119 return false; 120 } 121 122 bool DumpRegisterSet(const ExecutionContext &exe_ctx, Stream &strm, 123 RegisterContext *reg_ctx, size_t set_idx, 124 bool primitive_only = false) { 125 uint32_t unavailable_count = 0; 126 uint32_t available_count = 0; 127 128 if (!reg_ctx) 129 return false; // thread has no registers (i.e. core files are corrupt, 130 // incomplete crash logs...) 131 132 const RegisterSet *const reg_set = reg_ctx->GetRegisterSet(set_idx); 133 if (reg_set) { 134 strm.Printf("%s:\n", (reg_set->name ? reg_set->name : "unknown")); 135 strm.IndentMore(); 136 const size_t num_registers = reg_set->num_registers; 137 for (size_t reg_idx = 0; reg_idx < num_registers; ++reg_idx) { 138 const uint32_t reg = reg_set->registers[reg_idx]; 139 const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoAtIndex(reg); 140 // Skip the dumping of derived register if primitive_only is true. 141 if (primitive_only && reg_info && reg_info->value_regs) 142 continue; 143 144 if (DumpRegister(exe_ctx, strm, reg_ctx, reg_info)) 145 ++available_count; 146 else 147 ++unavailable_count; 148 } 149 strm.IndentLess(); 150 if (unavailable_count) { 151 strm.Indent(); 152 strm.Printf("%u registers were unavailable.\n", unavailable_count); 153 } 154 strm.EOL(); 155 } 156 return available_count > 0; 157 } 158 159 protected: 160 bool DoExecute(Args &command, CommandReturnObject &result) override { 161 Stream &strm = result.GetOutputStream(); 162 RegisterContext *reg_ctx = m_exe_ctx.GetRegisterContext(); 163 164 const RegisterInfo *reg_info = nullptr; 165 if (command.GetArgumentCount() == 0) { 166 size_t set_idx; 167 168 size_t num_register_sets = 1; 169 const size_t set_array_size = m_command_options.set_indexes.GetSize(); 170 if (set_array_size > 0) { 171 for (size_t i = 0; i < set_array_size; ++i) { 172 set_idx = m_command_options.set_indexes[i]->GetUInt64Value(UINT32_MAX, 173 nullptr); 174 if (set_idx < reg_ctx->GetRegisterSetCount()) { 175 if (!DumpRegisterSet(m_exe_ctx, strm, reg_ctx, set_idx)) { 176 if (errno) 177 result.AppendErrorWithFormatv("register read failed: {0}\n", 178 llvm::sys::StrError()); 179 else 180 result.AppendError("unknown error while reading registers.\n"); 181 break; 182 } 183 } else { 184 result.AppendErrorWithFormat( 185 "invalid register set index: %" PRIu64 "\n", (uint64_t)set_idx); 186 break; 187 } 188 } 189 } else { 190 if (m_command_options.dump_all_sets) 191 num_register_sets = reg_ctx->GetRegisterSetCount(); 192 193 for (set_idx = 0; set_idx < num_register_sets; ++set_idx) { 194 // When dump_all_sets option is set, dump primitive as well as 195 // derived registers. 196 DumpRegisterSet(m_exe_ctx, strm, reg_ctx, set_idx, 197 !m_command_options.dump_all_sets.GetCurrentValue()); 198 } 199 } 200 } else { 201 if (m_command_options.dump_all_sets) { 202 result.AppendError("the --all option can't be used when registers " 203 "names are supplied as arguments\n"); 204 } else if (m_command_options.set_indexes.GetSize() > 0) { 205 result.AppendError("the --set <set> option can't be used when " 206 "registers names are supplied as arguments\n"); 207 } else { 208 for (auto &entry : command) { 209 // in most LLDB commands we accept $rbx as the name for register RBX 210 // - and here we would reject it and non-existant. we should be more 211 // consistent towards the user and allow them to say reg read $rbx - 212 // internally, however, we should be strict and not allow ourselves 213 // to call our registers $rbx in our own API 214 auto arg_str = entry.ref(); 215 arg_str.consume_front("$"); 216 217 reg_info = reg_ctx->GetRegisterInfoByName(arg_str); 218 219 if (reg_info) { 220 if (!DumpRegister(m_exe_ctx, strm, reg_ctx, reg_info)) 221 strm.Printf("%-12s = error: unavailable\n", reg_info->name); 222 } else { 223 result.AppendErrorWithFormat("Invalid register name '%s'.\n", 224 arg_str.str().c_str()); 225 } 226 } 227 } 228 } 229 return result.Succeeded(); 230 } 231 232 class CommandOptions : public OptionGroup { 233 public: 234 CommandOptions() 235 : OptionGroup(), 236 set_indexes(OptionValue::ConvertTypeToMask(OptionValue::eTypeUInt64)), 237 dump_all_sets(false, false), // Initial and default values are false 238 alternate_name(false, false) {} 239 240 ~CommandOptions() override = default; 241 242 llvm::ArrayRef<OptionDefinition> GetDefinitions() override { 243 return llvm::makeArrayRef(g_register_read_options); 244 } 245 246 void OptionParsingStarting(ExecutionContext *execution_context) override { 247 set_indexes.Clear(); 248 dump_all_sets.Clear(); 249 alternate_name.Clear(); 250 } 251 252 Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_value, 253 ExecutionContext *execution_context) override { 254 Status error; 255 const int short_option = GetDefinitions()[option_idx].short_option; 256 switch (short_option) { 257 case 's': { 258 OptionValueSP value_sp(OptionValueUInt64::Create(option_value, error)); 259 if (value_sp) 260 set_indexes.AppendValue(value_sp); 261 } break; 262 263 case 'a': 264 // When we don't use OptionValue::SetValueFromCString(const char *) to 265 // set an option value, it won't be marked as being set in the options 266 // so we make a call to let users know the value was set via option 267 dump_all_sets.SetCurrentValue(true); 268 dump_all_sets.SetOptionWasSet(); 269 break; 270 271 case 'A': 272 // When we don't use OptionValue::SetValueFromCString(const char *) to 273 // set an option value, it won't be marked as being set in the options 274 // so we make a call to let users know the value was set via option 275 alternate_name.SetCurrentValue(true); 276 dump_all_sets.SetOptionWasSet(); 277 break; 278 279 default: 280 llvm_unreachable("Unimplemented option"); 281 } 282 return error; 283 } 284 285 // Instance variables to hold the values for command options. 286 OptionValueArray set_indexes; 287 OptionValueBoolean dump_all_sets; 288 OptionValueBoolean alternate_name; 289 }; 290 291 OptionGroupOptions m_option_group; 292 OptionGroupFormat m_format_options; 293 CommandOptions m_command_options; 294 }; 295 296 // "register write" 297 class CommandObjectRegisterWrite : public CommandObjectParsed { 298 public: 299 CommandObjectRegisterWrite(CommandInterpreter &interpreter) 300 : CommandObjectParsed(interpreter, "register write", 301 "Modify a single register value.", nullptr, 302 eCommandRequiresFrame | eCommandRequiresRegContext | 303 eCommandProcessMustBeLaunched | 304 eCommandProcessMustBePaused) { 305 CommandArgumentEntry arg1; 306 CommandArgumentEntry arg2; 307 CommandArgumentData register_arg; 308 CommandArgumentData value_arg; 309 310 // Define the first (and only) variant of this arg. 311 register_arg.arg_type = eArgTypeRegisterName; 312 register_arg.arg_repetition = eArgRepeatPlain; 313 314 // There is only one variant this argument could be; put it into the 315 // argument entry. 316 arg1.push_back(register_arg); 317 318 // Define the first (and only) variant of this arg. 319 value_arg.arg_type = eArgTypeValue; 320 value_arg.arg_repetition = eArgRepeatPlain; 321 322 // There is only one variant this argument could be; put it into the 323 // argument entry. 324 arg2.push_back(value_arg); 325 326 // Push the data for the first argument into the m_arguments vector. 327 m_arguments.push_back(arg1); 328 m_arguments.push_back(arg2); 329 } 330 331 ~CommandObjectRegisterWrite() override = default; 332 333 void 334 HandleArgumentCompletion(CompletionRequest &request, 335 OptionElementVector &opt_element_vector) override { 336 if (!m_exe_ctx.HasProcessScope() || request.GetCursorIndex() != 0) 337 return; 338 339 CommandCompletions::InvokeCommonCompletionCallbacks( 340 GetCommandInterpreter(), CommandCompletions::eRegisterCompletion, 341 request, nullptr); 342 } 343 344 protected: 345 bool DoExecute(Args &command, CommandReturnObject &result) override { 346 DataExtractor reg_data; 347 RegisterContext *reg_ctx = m_exe_ctx.GetRegisterContext(); 348 349 if (command.GetArgumentCount() != 2) { 350 result.AppendError( 351 "register write takes exactly 2 arguments: <reg-name> <value>"); 352 } else { 353 auto reg_name = command[0].ref(); 354 auto value_str = command[1].ref(); 355 356 // in most LLDB commands we accept $rbx as the name for register RBX - 357 // and here we would reject it and non-existant. we should be more 358 // consistent towards the user and allow them to say reg write $rbx - 359 // internally, however, we should be strict and not allow ourselves to 360 // call our registers $rbx in our own API 361 reg_name.consume_front("$"); 362 363 const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoByName(reg_name); 364 365 if (reg_info) { 366 RegisterValue reg_value; 367 368 Status error(reg_value.SetValueFromString(reg_info, value_str)); 369 if (error.Success()) { 370 if (reg_ctx->WriteRegister(reg_info, reg_value)) { 371 // Toss all frames and anything else in the thread after a register 372 // has been written. 373 m_exe_ctx.GetThreadRef().Flush(); 374 result.SetStatus(eReturnStatusSuccessFinishNoResult); 375 return true; 376 } 377 } 378 if (error.AsCString()) { 379 result.AppendErrorWithFormat( 380 "Failed to write register '%s' with value '%s': %s\n", 381 reg_name.str().c_str(), value_str.str().c_str(), 382 error.AsCString()); 383 } else { 384 result.AppendErrorWithFormat( 385 "Failed to write register '%s' with value '%s'", 386 reg_name.str().c_str(), value_str.str().c_str()); 387 } 388 } else { 389 result.AppendErrorWithFormat("Register not found for '%s'.\n", 390 reg_name.str().c_str()); 391 } 392 } 393 return result.Succeeded(); 394 } 395 }; 396 397 // CommandObjectRegister constructor 398 CommandObjectRegister::CommandObjectRegister(CommandInterpreter &interpreter) 399 : CommandObjectMultiword(interpreter, "register", 400 "Commands to access registers for the current " 401 "thread and stack frame.", 402 "register [read|write] ...") { 403 LoadSubCommand("read", 404 CommandObjectSP(new CommandObjectRegisterRead(interpreter))); 405 LoadSubCommand("write", 406 CommandObjectSP(new CommandObjectRegisterWrite(interpreter))); 407 } 408 409 CommandObjectRegister::~CommandObjectRegister() = default; 410