1 //===-- GDBRemoteRegisterContext.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 "GDBRemoteRegisterContext.h" 10 11 #include "ProcessGDBRemote.h" 12 #include "ProcessGDBRemoteLog.h" 13 #include "ThreadGDBRemote.h" 14 #include "Utility/ARM_DWARF_Registers.h" 15 #include "Utility/ARM_ehframe_Registers.h" 16 #include "lldb/Core/Architecture.h" 17 #include "lldb/Target/ExecutionContext.h" 18 #include "lldb/Target/Target.h" 19 #include "lldb/Utility/DataBufferHeap.h" 20 #include "lldb/Utility/DataExtractor.h" 21 #include "lldb/Utility/RegisterValue.h" 22 #include "lldb/Utility/Scalar.h" 23 #include "lldb/Utility/StreamString.h" 24 #include "lldb/Utility/StringExtractorGDBRemote.h" 25 26 #include <memory> 27 28 using namespace lldb; 29 using namespace lldb_private; 30 using namespace lldb_private::process_gdb_remote; 31 32 // GDBRemoteRegisterContext constructor 33 GDBRemoteRegisterContext::GDBRemoteRegisterContext( 34 ThreadGDBRemote &thread, uint32_t concrete_frame_idx, 35 GDBRemoteDynamicRegisterInfoSP reg_info_sp, bool read_all_at_once, 36 bool write_all_at_once) 37 : RegisterContext(thread, concrete_frame_idx), 38 m_reg_info_sp(std::move(reg_info_sp)), m_reg_valid(), m_reg_data(), 39 m_read_all_at_once(read_all_at_once), 40 m_write_all_at_once(write_all_at_once), m_gpacket_cached(false) { 41 // Resize our vector of bools to contain one bool for every register. We will 42 // use these boolean values to know when a register value is valid in 43 // m_reg_data. 44 m_reg_valid.resize(m_reg_info_sp->GetNumRegisters()); 45 46 // Make a heap based buffer that is big enough to store all registers 47 DataBufferSP reg_data_sp( 48 new DataBufferHeap(m_reg_info_sp->GetRegisterDataByteSize(), 0)); 49 m_reg_data.SetData(reg_data_sp); 50 m_reg_data.SetByteOrder(thread.GetProcess()->GetByteOrder()); 51 } 52 53 // Destructor 54 GDBRemoteRegisterContext::~GDBRemoteRegisterContext() = default; 55 56 void GDBRemoteRegisterContext::InvalidateAllRegisters() { 57 SetAllRegisterValid(false); 58 } 59 60 void GDBRemoteRegisterContext::SetAllRegisterValid(bool b) { 61 m_gpacket_cached = b; 62 std::vector<bool>::iterator pos, end = m_reg_valid.end(); 63 for (pos = m_reg_valid.begin(); pos != end; ++pos) 64 *pos = b; 65 } 66 67 size_t GDBRemoteRegisterContext::GetRegisterCount() { 68 return m_reg_info_sp->GetNumRegisters(); 69 } 70 71 const RegisterInfo * 72 GDBRemoteRegisterContext::GetRegisterInfoAtIndex(size_t reg) { 73 return m_reg_info_sp->GetRegisterInfoAtIndex(reg); 74 } 75 76 size_t GDBRemoteRegisterContext::GetRegisterSetCount() { 77 return m_reg_info_sp->GetNumRegisterSets(); 78 } 79 80 const RegisterSet *GDBRemoteRegisterContext::GetRegisterSet(size_t reg_set) { 81 return m_reg_info_sp->GetRegisterSet(reg_set); 82 } 83 84 bool GDBRemoteRegisterContext::ReadRegister(const RegisterInfo *reg_info, 85 RegisterValue &value) { 86 // Read the register 87 if (ReadRegisterBytes(reg_info)) { 88 const uint32_t reg = reg_info->kinds[eRegisterKindLLDB]; 89 if (m_reg_valid[reg] == false) 90 return false; 91 if (reg_info->value_regs && 92 reg_info->value_regs[0] != LLDB_INVALID_REGNUM && 93 reg_info->value_regs[1] != LLDB_INVALID_REGNUM) { 94 std::vector<char> combined_data; 95 uint32_t offset = 0; 96 for (int i = 0; reg_info->value_regs[i] != LLDB_INVALID_REGNUM; i++) { 97 const RegisterInfo *parent_reg = GetRegisterInfo( 98 eRegisterKindLLDB, reg_info->value_regs[i]); 99 if (!parent_reg) 100 return false; 101 combined_data.resize(offset + parent_reg->byte_size); 102 if (m_reg_data.CopyData(parent_reg->byte_offset, parent_reg->byte_size, 103 combined_data.data() + offset) != 104 parent_reg->byte_size) 105 return false; 106 offset += parent_reg->byte_size; 107 } 108 109 Status error; 110 return value.SetFromMemoryData( 111 *reg_info, combined_data.data(), combined_data.size(), 112 m_reg_data.GetByteOrder(), error) == combined_data.size(); 113 } else { 114 const bool partial_data_ok = false; 115 Status error(value.SetValueFromData( 116 *reg_info, m_reg_data, reg_info->byte_offset, partial_data_ok)); 117 return error.Success(); 118 } 119 } 120 return false; 121 } 122 123 bool GDBRemoteRegisterContext::PrivateSetRegisterValue( 124 uint32_t reg, llvm::ArrayRef<uint8_t> data) { 125 const RegisterInfo *reg_info = GetRegisterInfoAtIndex(reg); 126 if (reg_info == nullptr) 127 return false; 128 129 // Invalidate if needed 130 InvalidateIfNeeded(false); 131 132 const size_t reg_byte_size = reg_info->byte_size; 133 memcpy(const_cast<uint8_t *>( 134 m_reg_data.PeekData(reg_info->byte_offset, reg_byte_size)), 135 data.data(), std::min(data.size(), reg_byte_size)); 136 bool success = data.size() >= reg_byte_size; 137 if (success) { 138 SetRegisterIsValid(reg, true); 139 } else if (data.size() > 0) { 140 // Only set register is valid to false if we copied some bytes, else leave 141 // it as it was. 142 SetRegisterIsValid(reg, false); 143 } 144 return success; 145 } 146 147 bool GDBRemoteRegisterContext::PrivateSetRegisterValue(uint32_t reg, 148 uint64_t new_reg_val) { 149 const RegisterInfo *reg_info = GetRegisterInfoAtIndex(reg); 150 if (reg_info == nullptr) 151 return false; 152 153 // Early in process startup, we can get a thread that has an invalid byte 154 // order because the process hasn't been completely set up yet (see the ctor 155 // where the byte order is setfrom the process). If that's the case, we 156 // can't set the value here. 157 if (m_reg_data.GetByteOrder() == eByteOrderInvalid) { 158 return false; 159 } 160 161 // Invalidate if needed 162 InvalidateIfNeeded(false); 163 164 DataBufferSP buffer_sp(new DataBufferHeap(&new_reg_val, sizeof(new_reg_val))); 165 DataExtractor data(buffer_sp, endian::InlHostByteOrder(), sizeof(void *)); 166 167 // If our register context and our register info disagree, which should never 168 // happen, don't overwrite past the end of the buffer. 169 if (m_reg_data.GetByteSize() < reg_info->byte_offset + reg_info->byte_size) 170 return false; 171 172 // Grab a pointer to where we are going to put this register 173 uint8_t *dst = const_cast<uint8_t *>( 174 m_reg_data.PeekData(reg_info->byte_offset, reg_info->byte_size)); 175 176 if (dst == nullptr) 177 return false; 178 179 if (data.CopyByteOrderedData(0, // src offset 180 reg_info->byte_size, // src length 181 dst, // dst 182 reg_info->byte_size, // dst length 183 m_reg_data.GetByteOrder())) // dst byte order 184 { 185 SetRegisterIsValid(reg, true); 186 return true; 187 } 188 return false; 189 } 190 191 // Helper function for GDBRemoteRegisterContext::ReadRegisterBytes(). 192 bool GDBRemoteRegisterContext::GetPrimordialRegister( 193 const RegisterInfo *reg_info, GDBRemoteCommunicationClient &gdb_comm) { 194 const uint32_t lldb_reg = reg_info->kinds[eRegisterKindLLDB]; 195 const uint32_t remote_reg = reg_info->kinds[eRegisterKindProcessPlugin]; 196 197 if (DataBufferSP buffer_sp = 198 gdb_comm.ReadRegister(m_thread.GetProtocolID(), remote_reg)) 199 return PrivateSetRegisterValue( 200 lldb_reg, llvm::ArrayRef<uint8_t>(buffer_sp->GetBytes(), 201 buffer_sp->GetByteSize())); 202 return false; 203 } 204 205 bool GDBRemoteRegisterContext::ReadRegisterBytes(const RegisterInfo *reg_info) { 206 ExecutionContext exe_ctx(CalculateThread()); 207 208 Process *process = exe_ctx.GetProcessPtr(); 209 Thread *thread = exe_ctx.GetThreadPtr(); 210 if (process == nullptr || thread == nullptr) 211 return false; 212 213 GDBRemoteCommunicationClient &gdb_comm( 214 ((ProcessGDBRemote *)process)->GetGDBRemote()); 215 216 InvalidateIfNeeded(false); 217 218 const uint32_t reg = reg_info->kinds[eRegisterKindLLDB]; 219 220 if (!GetRegisterIsValid(reg)) { 221 if (m_read_all_at_once && !m_gpacket_cached) { 222 if (DataBufferSP buffer_sp = 223 gdb_comm.ReadAllRegisters(m_thread.GetProtocolID())) { 224 memcpy(const_cast<uint8_t *>(m_reg_data.GetDataStart()), 225 buffer_sp->GetBytes(), 226 std::min(buffer_sp->GetByteSize(), m_reg_data.GetByteSize())); 227 if (buffer_sp->GetByteSize() >= m_reg_data.GetByteSize()) { 228 SetAllRegisterValid(true); 229 return true; 230 } else if (buffer_sp->GetByteSize() > 0) { 231 for (auto x : llvm::enumerate(m_reg_info_sp->registers())) { 232 const struct RegisterInfo ®info = x.value(); 233 m_reg_valid[x.index()] = 234 (reginfo.byte_offset + reginfo.byte_size <= 235 buffer_sp->GetByteSize()); 236 } 237 238 m_gpacket_cached = true; 239 if (GetRegisterIsValid(reg)) 240 return true; 241 } else { 242 Log *log(GetLog(GDBRLog::Thread | GDBRLog::Packets)); 243 LLDB_LOGF( 244 log, 245 "error: GDBRemoteRegisterContext::ReadRegisterBytes tried " 246 "to read the " 247 "entire register context at once, expected at least %" PRId64 248 " bytes " 249 "but only got %" PRId64 " bytes.", 250 m_reg_data.GetByteSize(), buffer_sp->GetByteSize()); 251 return false; 252 } 253 } 254 } 255 if (reg_info->value_regs) { 256 // Process this composite register request by delegating to the 257 // constituent primordial registers. 258 259 // Index of the primordial register. 260 bool success = true; 261 for (uint32_t idx = 0; success; ++idx) { 262 const uint32_t prim_reg = reg_info->value_regs[idx]; 263 if (prim_reg == LLDB_INVALID_REGNUM) 264 break; 265 // We have a valid primordial register as our constituent. Grab the 266 // corresponding register info. 267 const RegisterInfo *prim_reg_info = 268 GetRegisterInfo(eRegisterKindLLDB, prim_reg); 269 if (prim_reg_info == nullptr) 270 success = false; 271 else { 272 // Read the containing register if it hasn't already been read 273 if (!GetRegisterIsValid(prim_reg)) 274 success = GetPrimordialRegister(prim_reg_info, gdb_comm); 275 } 276 } 277 278 if (success) { 279 // If we reach this point, all primordial register requests have 280 // succeeded. Validate this composite register. 281 SetRegisterIsValid(reg_info, true); 282 } 283 } else { 284 // Get each register individually 285 GetPrimordialRegister(reg_info, gdb_comm); 286 } 287 288 // Make sure we got a valid register value after reading it 289 if (!GetRegisterIsValid(reg)) 290 return false; 291 } 292 293 return true; 294 } 295 296 bool GDBRemoteRegisterContext::WriteRegister(const RegisterInfo *reg_info, 297 const RegisterValue &value) { 298 DataExtractor data; 299 if (value.GetData(data)) { 300 if (reg_info->value_regs && 301 reg_info->value_regs[0] != LLDB_INVALID_REGNUM && 302 reg_info->value_regs[1] != LLDB_INVALID_REGNUM) { 303 uint32_t combined_size = 0; 304 for (int i = 0; reg_info->value_regs[i] != LLDB_INVALID_REGNUM; i++) { 305 const RegisterInfo *parent_reg = GetRegisterInfo( 306 eRegisterKindLLDB, reg_info->value_regs[i]); 307 if (!parent_reg) 308 return false; 309 combined_size += parent_reg->byte_size; 310 } 311 312 if (data.GetByteSize() < combined_size) 313 return false; 314 315 uint32_t offset = 0; 316 for (int i = 0; reg_info->value_regs[i] != LLDB_INVALID_REGNUM; i++) { 317 const RegisterInfo *parent_reg = GetRegisterInfo( 318 eRegisterKindLLDB, reg_info->value_regs[i]); 319 assert(parent_reg); 320 321 DataExtractor parent_data{data, offset, parent_reg->byte_size}; 322 if (!WriteRegisterBytes(parent_reg, parent_data, 0)) 323 return false; 324 offset += parent_reg->byte_size; 325 } 326 assert(offset == combined_size); 327 return true; 328 } else 329 return WriteRegisterBytes(reg_info, data, 0); 330 } 331 return false; 332 } 333 334 // Helper function for GDBRemoteRegisterContext::WriteRegisterBytes(). 335 bool GDBRemoteRegisterContext::SetPrimordialRegister( 336 const RegisterInfo *reg_info, GDBRemoteCommunicationClient &gdb_comm) { 337 StreamString packet; 338 StringExtractorGDBRemote response; 339 const uint32_t reg = reg_info->kinds[eRegisterKindLLDB]; 340 // Invalidate just this register 341 SetRegisterIsValid(reg, false); 342 343 return gdb_comm.WriteRegister( 344 m_thread.GetProtocolID(), reg_info->kinds[eRegisterKindProcessPlugin], 345 {m_reg_data.PeekData(reg_info->byte_offset, reg_info->byte_size), 346 reg_info->byte_size}); 347 } 348 349 bool GDBRemoteRegisterContext::WriteRegisterBytes(const RegisterInfo *reg_info, 350 DataExtractor &data, 351 uint32_t data_offset) { 352 ExecutionContext exe_ctx(CalculateThread()); 353 354 Process *process = exe_ctx.GetProcessPtr(); 355 Thread *thread = exe_ctx.GetThreadPtr(); 356 if (process == nullptr || thread == nullptr) 357 return false; 358 359 GDBRemoteCommunicationClient &gdb_comm( 360 ((ProcessGDBRemote *)process)->GetGDBRemote()); 361 362 assert(m_reg_data.GetByteSize() >= 363 reg_info->byte_offset + reg_info->byte_size); 364 365 // If our register context and our register info disagree, which should never 366 // happen, don't overwrite past the end of the buffer. 367 if (m_reg_data.GetByteSize() < reg_info->byte_offset + reg_info->byte_size) 368 return false; 369 370 // Grab a pointer to where we are going to put this register 371 uint8_t *dst = const_cast<uint8_t *>( 372 m_reg_data.PeekData(reg_info->byte_offset, reg_info->byte_size)); 373 374 if (dst == nullptr) 375 return false; 376 377 const bool should_reconfigure_registers = 378 RegisterWriteCausesReconfigure(reg_info->name); 379 380 if (data.CopyByteOrderedData(data_offset, // src offset 381 reg_info->byte_size, // src length 382 dst, // dst 383 reg_info->byte_size, // dst length 384 m_reg_data.GetByteOrder())) // dst byte order 385 { 386 GDBRemoteClientBase::Lock lock(gdb_comm); 387 if (lock) { 388 if (m_write_all_at_once) { 389 // Invalidate all register values 390 InvalidateIfNeeded(true); 391 392 // Set all registers in one packet 393 if (gdb_comm.WriteAllRegisters( 394 m_thread.GetProtocolID(), 395 {m_reg_data.GetDataStart(), size_t(m_reg_data.GetByteSize())})) 396 397 { 398 if (should_reconfigure_registers) 399 ReconfigureRegisterInfo(); 400 401 InvalidateAllRegisters(); 402 403 return true; 404 } 405 } else { 406 bool success = true; 407 408 if (reg_info->value_regs) { 409 // This register is part of another register. In this case we read 410 // the actual register data for any "value_regs", and once all that 411 // data is read, we will have enough data in our register context 412 // bytes for the value of this register 413 414 // Invalidate this composite register first. 415 416 for (uint32_t idx = 0; success; ++idx) { 417 const uint32_t reg = reg_info->value_regs[idx]; 418 if (reg == LLDB_INVALID_REGNUM) 419 break; 420 // We have a valid primordial register as our constituent. Grab the 421 // corresponding register info. 422 const RegisterInfo *value_reg_info = 423 GetRegisterInfo(eRegisterKindLLDB, reg); 424 if (value_reg_info == nullptr) 425 success = false; 426 else 427 success = SetPrimordialRegister(value_reg_info, gdb_comm); 428 } 429 } else { 430 // This is an actual register, write it 431 success = SetPrimordialRegister(reg_info, gdb_comm); 432 } 433 434 // Check if writing this register will invalidate any other register 435 // values? If so, invalidate them 436 if (reg_info->invalidate_regs) { 437 for (uint32_t idx = 0, reg = reg_info->invalidate_regs[0]; 438 reg != LLDB_INVALID_REGNUM; 439 reg = reg_info->invalidate_regs[++idx]) 440 SetRegisterIsValid(ConvertRegisterKindToRegisterNumber( 441 eRegisterKindLLDB, reg), 442 false); 443 } 444 445 if (success && should_reconfigure_registers && 446 ReconfigureRegisterInfo()) 447 InvalidateAllRegisters(); 448 449 return success; 450 } 451 } else { 452 Log *log(GetLog(GDBRLog::Thread | GDBRLog::Packets)); 453 if (log) { 454 if (log->GetVerbose()) { 455 StreamString strm; 456 process->DumpPluginHistory(strm); 457 LLDB_LOGF(log, 458 "error: failed to get packet sequence mutex, not sending " 459 "write register for \"%s\":\n%s", 460 reg_info->name, strm.GetData()); 461 } else 462 LLDB_LOGF(log, 463 "error: failed to get packet sequence mutex, not sending " 464 "write register for \"%s\"", 465 reg_info->name); 466 } 467 } 468 } 469 return false; 470 } 471 472 bool GDBRemoteRegisterContext::ReadAllRegisterValues( 473 RegisterCheckpoint ®_checkpoint) { 474 ExecutionContext exe_ctx(CalculateThread()); 475 476 Process *process = exe_ctx.GetProcessPtr(); 477 Thread *thread = exe_ctx.GetThreadPtr(); 478 if (process == nullptr || thread == nullptr) 479 return false; 480 481 GDBRemoteCommunicationClient &gdb_comm( 482 ((ProcessGDBRemote *)process)->GetGDBRemote()); 483 484 uint32_t save_id = 0; 485 if (gdb_comm.SaveRegisterState(thread->GetProtocolID(), save_id)) { 486 reg_checkpoint.SetID(save_id); 487 reg_checkpoint.GetData().reset(); 488 return true; 489 } else { 490 reg_checkpoint.SetID(0); // Invalid save ID is zero 491 return ReadAllRegisterValues(reg_checkpoint.GetData()); 492 } 493 } 494 495 bool GDBRemoteRegisterContext::WriteAllRegisterValues( 496 const RegisterCheckpoint ®_checkpoint) { 497 uint32_t save_id = reg_checkpoint.GetID(); 498 if (save_id != 0) { 499 ExecutionContext exe_ctx(CalculateThread()); 500 501 Process *process = exe_ctx.GetProcessPtr(); 502 Thread *thread = exe_ctx.GetThreadPtr(); 503 if (process == nullptr || thread == nullptr) 504 return false; 505 506 GDBRemoteCommunicationClient &gdb_comm( 507 ((ProcessGDBRemote *)process)->GetGDBRemote()); 508 509 return gdb_comm.RestoreRegisterState(m_thread.GetProtocolID(), save_id); 510 } else { 511 return WriteAllRegisterValues(reg_checkpoint.GetData()); 512 } 513 } 514 515 bool GDBRemoteRegisterContext::ReadAllRegisterValues( 516 lldb::WritableDataBufferSP &data_sp) { 517 ExecutionContext exe_ctx(CalculateThread()); 518 519 Process *process = exe_ctx.GetProcessPtr(); 520 Thread *thread = exe_ctx.GetThreadPtr(); 521 if (process == nullptr || thread == nullptr) 522 return false; 523 524 GDBRemoteCommunicationClient &gdb_comm( 525 ((ProcessGDBRemote *)process)->GetGDBRemote()); 526 527 const bool use_g_packet = 528 !gdb_comm.AvoidGPackets((ProcessGDBRemote *)process); 529 530 GDBRemoteClientBase::Lock lock(gdb_comm); 531 if (lock) { 532 if (gdb_comm.SyncThreadState(m_thread.GetProtocolID())) 533 InvalidateAllRegisters(); 534 535 if (use_g_packet) { 536 if (DataBufferSP data_buffer = 537 gdb_comm.ReadAllRegisters(m_thread.GetProtocolID())) { 538 data_sp = std::make_shared<DataBufferHeap>(*data_buffer); 539 return true; 540 } 541 } 542 543 // We're going to read each register 544 // individually and store them as binary data in a buffer. 545 const RegisterInfo *reg_info; 546 547 for (uint32_t i = 0; (reg_info = GetRegisterInfoAtIndex(i)) != nullptr; 548 i++) { 549 if (reg_info 550 ->value_regs) // skip registers that are slices of real registers 551 continue; 552 ReadRegisterBytes(reg_info); 553 // ReadRegisterBytes saves the contents of the register in to the 554 // m_reg_data buffer 555 } 556 data_sp = std::make_shared<DataBufferHeap>( 557 m_reg_data.GetDataStart(), m_reg_info_sp->GetRegisterDataByteSize()); 558 return true; 559 } else { 560 561 Log *log(GetLog(GDBRLog::Thread | GDBRLog::Packets)); 562 if (log) { 563 if (log->GetVerbose()) { 564 StreamString strm; 565 process->DumpPluginHistory(strm); 566 LLDB_LOGF(log, 567 "error: failed to get packet sequence mutex, not sending " 568 "read all registers:\n%s", 569 strm.GetData()); 570 } else 571 LLDB_LOGF(log, 572 "error: failed to get packet sequence mutex, not sending " 573 "read all registers"); 574 } 575 } 576 577 data_sp.reset(); 578 return false; 579 } 580 581 bool GDBRemoteRegisterContext::WriteAllRegisterValues( 582 const lldb::DataBufferSP &data_sp) { 583 if (!data_sp || data_sp->GetBytes() == nullptr || data_sp->GetByteSize() == 0) 584 return false; 585 586 ExecutionContext exe_ctx(CalculateThread()); 587 588 Process *process = exe_ctx.GetProcessPtr(); 589 Thread *thread = exe_ctx.GetThreadPtr(); 590 if (process == nullptr || thread == nullptr) 591 return false; 592 593 GDBRemoteCommunicationClient &gdb_comm( 594 ((ProcessGDBRemote *)process)->GetGDBRemote()); 595 596 const bool use_g_packet = 597 !gdb_comm.AvoidGPackets((ProcessGDBRemote *)process); 598 599 GDBRemoteClientBase::Lock lock(gdb_comm); 600 if (lock) { 601 // The data_sp contains the G response packet. 602 if (use_g_packet) { 603 if (gdb_comm.WriteAllRegisters( 604 m_thread.GetProtocolID(), 605 {data_sp->GetBytes(), size_t(data_sp->GetByteSize())})) 606 return true; 607 608 uint32_t num_restored = 0; 609 // We need to manually go through all of the registers and restore them 610 // manually 611 DataExtractor restore_data(data_sp, m_reg_data.GetByteOrder(), 612 m_reg_data.GetAddressByteSize()); 613 614 const RegisterInfo *reg_info; 615 616 // The g packet contents may either include the slice registers 617 // (registers defined in terms of other registers, e.g. eax is a subset 618 // of rax) or not. The slice registers should NOT be in the g packet, 619 // but some implementations may incorrectly include them. 620 // 621 // If the slice registers are included in the packet, we must step over 622 // the slice registers when parsing the packet -- relying on the 623 // RegisterInfo byte_offset field would be incorrect. If the slice 624 // registers are not included, then using the byte_offset values into the 625 // data buffer is the best way to find individual register values. 626 627 uint64_t size_including_slice_registers = 0; 628 uint64_t size_not_including_slice_registers = 0; 629 uint64_t size_by_highest_offset = 0; 630 631 for (uint32_t reg_idx = 0; 632 (reg_info = GetRegisterInfoAtIndex(reg_idx)) != nullptr; ++reg_idx) { 633 size_including_slice_registers += reg_info->byte_size; 634 if (reg_info->value_regs == nullptr) 635 size_not_including_slice_registers += reg_info->byte_size; 636 if (reg_info->byte_offset >= size_by_highest_offset) 637 size_by_highest_offset = reg_info->byte_offset + reg_info->byte_size; 638 } 639 640 bool use_byte_offset_into_buffer; 641 if (size_by_highest_offset == restore_data.GetByteSize()) { 642 // The size of the packet agrees with the highest offset: + size in the 643 // register file 644 use_byte_offset_into_buffer = true; 645 } else if (size_not_including_slice_registers == 646 restore_data.GetByteSize()) { 647 // The size of the packet is the same as concatenating all of the 648 // registers sequentially, skipping the slice registers 649 use_byte_offset_into_buffer = true; 650 } else if (size_including_slice_registers == restore_data.GetByteSize()) { 651 // The slice registers are present in the packet (when they shouldn't 652 // be). Don't try to use the RegisterInfo byte_offset into the 653 // restore_data, it will point to the wrong place. 654 use_byte_offset_into_buffer = false; 655 } else { 656 // None of our expected sizes match the actual g packet data we're 657 // looking at. The most conservative approach here is to use the 658 // running total byte offset. 659 use_byte_offset_into_buffer = false; 660 } 661 662 // In case our register definitions don't include the correct offsets, 663 // keep track of the size of each reg & compute offset based on that. 664 uint32_t running_byte_offset = 0; 665 for (uint32_t reg_idx = 0; 666 (reg_info = GetRegisterInfoAtIndex(reg_idx)) != nullptr; 667 ++reg_idx, running_byte_offset += reg_info->byte_size) { 668 // Skip composite aka slice registers (e.g. eax is a slice of rax). 669 if (reg_info->value_regs) 670 continue; 671 672 const uint32_t reg = reg_info->kinds[eRegisterKindLLDB]; 673 674 uint32_t register_offset; 675 if (use_byte_offset_into_buffer) { 676 register_offset = reg_info->byte_offset; 677 } else { 678 register_offset = running_byte_offset; 679 } 680 681 const uint32_t reg_byte_size = reg_info->byte_size; 682 683 const uint8_t *restore_src = 684 restore_data.PeekData(register_offset, reg_byte_size); 685 if (restore_src) { 686 SetRegisterIsValid(reg, false); 687 if (gdb_comm.WriteRegister( 688 m_thread.GetProtocolID(), 689 reg_info->kinds[eRegisterKindProcessPlugin], 690 {restore_src, reg_byte_size})) 691 ++num_restored; 692 } 693 } 694 return num_restored > 0; 695 } else { 696 // For the use_g_packet == false case, we're going to write each register 697 // individually. The data buffer is binary data in this case, instead of 698 // ascii characters. 699 700 bool arm64_debugserver = false; 701 if (m_thread.GetProcess().get()) { 702 const ArchSpec &arch = 703 m_thread.GetProcess()->GetTarget().GetArchitecture(); 704 if (arch.IsValid() && (arch.GetMachine() == llvm::Triple::aarch64 || 705 arch.GetMachine() == llvm::Triple::aarch64_32) && 706 arch.GetTriple().getVendor() == llvm::Triple::Apple && 707 arch.GetTriple().getOS() == llvm::Triple::IOS) { 708 arm64_debugserver = true; 709 } 710 } 711 uint32_t num_restored = 0; 712 const RegisterInfo *reg_info; 713 for (uint32_t i = 0; (reg_info = GetRegisterInfoAtIndex(i)) != nullptr; 714 i++) { 715 if (reg_info->value_regs) // skip registers that are slices of real 716 // registers 717 continue; 718 // Skip the fpsr and fpcr floating point status/control register 719 // writing to work around a bug in an older version of debugserver that 720 // would lead to register context corruption when writing fpsr/fpcr. 721 if (arm64_debugserver && (strcmp(reg_info->name, "fpsr") == 0 || 722 strcmp(reg_info->name, "fpcr") == 0)) { 723 continue; 724 } 725 726 SetRegisterIsValid(reg_info, false); 727 if (gdb_comm.WriteRegister(m_thread.GetProtocolID(), 728 reg_info->kinds[eRegisterKindProcessPlugin], 729 {data_sp->GetBytes() + reg_info->byte_offset, 730 reg_info->byte_size})) 731 ++num_restored; 732 } 733 return num_restored > 0; 734 } 735 } else { 736 Log *log(GetLog(GDBRLog::Thread | GDBRLog::Packets)); 737 if (log) { 738 if (log->GetVerbose()) { 739 StreamString strm; 740 process->DumpPluginHistory(strm); 741 LLDB_LOGF(log, 742 "error: failed to get packet sequence mutex, not sending " 743 "write all registers:\n%s", 744 strm.GetData()); 745 } else 746 LLDB_LOGF(log, 747 "error: failed to get packet sequence mutex, not sending " 748 "write all registers"); 749 } 750 } 751 return false; 752 } 753 754 uint32_t GDBRemoteRegisterContext::ConvertRegisterKindToRegisterNumber( 755 lldb::RegisterKind kind, uint32_t num) { 756 return m_reg_info_sp->ConvertRegisterKindToRegisterNumber(kind, num); 757 } 758 759 bool GDBRemoteRegisterContext::RegisterWriteCausesReconfigure( 760 const llvm::StringRef name) { 761 ExecutionContext exe_ctx(CalculateThread()); 762 const Architecture *architecture = 763 exe_ctx.GetProcessRef().GetTarget().GetArchitecturePlugin(); 764 return architecture && architecture->RegisterWriteCausesReconfigure(name); 765 } 766 767 bool GDBRemoteRegisterContext::ReconfigureRegisterInfo() { 768 ExecutionContext exe_ctx(CalculateThread()); 769 const Architecture *architecture = 770 exe_ctx.GetProcessRef().GetTarget().GetArchitecturePlugin(); 771 if (architecture) 772 return architecture->ReconfigureRegisterInfo(*(m_reg_info_sp.get()), 773 m_reg_data, *this); 774 return false; 775 } 776