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 "lldb/Target/ExecutionContext.h" 12 #include "lldb/Target/Target.h" 13 #include "lldb/Utility/DataBufferHeap.h" 14 #include "lldb/Utility/DataExtractor.h" 15 #include "lldb/Utility/RegisterValue.h" 16 #include "lldb/Utility/Scalar.h" 17 #include "lldb/Utility/StreamString.h" 18 #include "ProcessGDBRemote.h" 19 #include "ProcessGDBRemoteLog.h" 20 #include "ThreadGDBRemote.h" 21 #include "Utility/ARM_DWARF_Registers.h" 22 #include "Utility/ARM_ehframe_Registers.h" 23 #include "lldb/Utility/StringExtractorGDBRemote.h" 24 25 #include <memory> 26 27 using namespace lldb; 28 using namespace lldb_private; 29 using namespace lldb_private::process_gdb_remote; 30 31 // GDBRemoteRegisterContext constructor 32 GDBRemoteRegisterContext::GDBRemoteRegisterContext( 33 ThreadGDBRemote &thread, uint32_t concrete_frame_idx, 34 GDBRemoteDynamicRegisterInfoSP reg_info_sp, bool read_all_at_once, 35 bool write_all_at_once) 36 : RegisterContext(thread, concrete_frame_idx), 37 m_reg_info_sp(std::move(reg_info_sp)), m_reg_valid(), m_reg_data(), 38 m_read_all_at_once(read_all_at_once), 39 m_write_all_at_once(write_all_at_once), m_gpacket_cached(false) { 40 // Resize our vector of bools to contain one bool for every register. We will 41 // use these boolean values to know when a register value is valid in 42 // m_reg_data. 43 m_reg_valid.resize(m_reg_info_sp->GetNumRegisters()); 44 45 // Make a heap based buffer that is big enough to store all registers 46 DataBufferSP reg_data_sp( 47 new DataBufferHeap(m_reg_info_sp->GetRegisterDataByteSize(), 0)); 48 m_reg_data.SetData(reg_data_sp); 49 m_reg_data.SetByteOrder(thread.GetProcess()->GetByteOrder()); 50 } 51 52 // Destructor 53 GDBRemoteRegisterContext::~GDBRemoteRegisterContext() = default; 54 55 void GDBRemoteRegisterContext::InvalidateAllRegisters() { 56 SetAllRegisterValid(false); 57 } 58 59 void GDBRemoteRegisterContext::SetAllRegisterValid(bool b) { 60 m_gpacket_cached = b; 61 std::vector<bool>::iterator pos, end = m_reg_valid.end(); 62 for (pos = m_reg_valid.begin(); pos != end; ++pos) 63 *pos = b; 64 } 65 66 size_t GDBRemoteRegisterContext::GetRegisterCount() { 67 return m_reg_info_sp->GetNumRegisters(); 68 } 69 70 const RegisterInfo * 71 GDBRemoteRegisterContext::GetRegisterInfoAtIndex(size_t reg) { 72 return m_reg_info_sp->GetRegisterInfoAtIndex(reg); 73 } 74 75 size_t GDBRemoteRegisterContext::GetRegisterSetCount() { 76 return m_reg_info_sp->GetNumRegisterSets(); 77 } 78 79 const RegisterSet *GDBRemoteRegisterContext::GetRegisterSet(size_t reg_set) { 80 return m_reg_info_sp->GetRegisterSet(reg_set); 81 } 82 83 bool GDBRemoteRegisterContext::ReadRegister(const RegisterInfo *reg_info, 84 RegisterValue &value) { 85 // Read the register 86 if (ReadRegisterBytes(reg_info)) { 87 const uint32_t reg = reg_info->kinds[eRegisterKindLLDB]; 88 if (m_reg_valid[reg] == false) 89 return false; 90 if (reg_info->value_regs && 91 reg_info->value_regs[0] != LLDB_INVALID_REGNUM && 92 reg_info->value_regs[1] != LLDB_INVALID_REGNUM) { 93 std::vector<char> combined_data; 94 uint32_t offset = 0; 95 for (int i = 0; reg_info->value_regs[i] != LLDB_INVALID_REGNUM; i++) { 96 const RegisterInfo *parent_reg = GetRegisterInfo( 97 eRegisterKindLLDB, reg_info->value_regs[i]); 98 if (!parent_reg) 99 return false; 100 combined_data.resize(offset + parent_reg->byte_size); 101 if (m_reg_data.CopyData(parent_reg->byte_offset, parent_reg->byte_size, 102 combined_data.data() + offset) != 103 parent_reg->byte_size) 104 return false; 105 offset += parent_reg->byte_size; 106 } 107 108 Status error; 109 return value.SetFromMemoryData( 110 *reg_info, combined_data.data(), combined_data.size(), 111 m_reg_data.GetByteOrder(), error) == combined_data.size(); 112 } else { 113 const bool partial_data_ok = false; 114 Status error(value.SetValueFromData( 115 *reg_info, m_reg_data, reg_info->byte_offset, partial_data_ok)); 116 return error.Success(); 117 } 118 } 119 return false; 120 } 121 122 bool GDBRemoteRegisterContext::PrivateSetRegisterValue( 123 uint32_t reg, llvm::ArrayRef<uint8_t> data) { 124 const RegisterInfo *reg_info = GetRegisterInfoAtIndex(reg); 125 if (reg_info == nullptr) 126 return false; 127 128 // Invalidate if needed 129 InvalidateIfNeeded(false); 130 131 const size_t reg_byte_size = reg_info->byte_size; 132 memcpy(const_cast<uint8_t *>( 133 m_reg_data.PeekData(reg_info->byte_offset, reg_byte_size)), 134 data.data(), std::min(data.size(), reg_byte_size)); 135 bool success = data.size() >= reg_byte_size; 136 if (success) { 137 SetRegisterIsValid(reg, true); 138 } else if (data.size() > 0) { 139 // Only set register is valid to false if we copied some bytes, else leave 140 // it as it was. 141 SetRegisterIsValid(reg, false); 142 } 143 return success; 144 } 145 146 bool GDBRemoteRegisterContext::PrivateSetRegisterValue(uint32_t reg, 147 uint64_t new_reg_val) { 148 const RegisterInfo *reg_info = GetRegisterInfoAtIndex(reg); 149 if (reg_info == nullptr) 150 return false; 151 152 // Early in process startup, we can get a thread that has an invalid byte 153 // order because the process hasn't been completely set up yet (see the ctor 154 // where the byte order is setfrom the process). If that's the case, we 155 // can't set the value here. 156 if (m_reg_data.GetByteOrder() == eByteOrderInvalid) { 157 return false; 158 } 159 160 // Invalidate if needed 161 InvalidateIfNeeded(false); 162 163 DataBufferSP buffer_sp(new DataBufferHeap(&new_reg_val, sizeof(new_reg_val))); 164 DataExtractor data(buffer_sp, endian::InlHostByteOrder(), sizeof(void *)); 165 166 // If our register context and our register info disagree, which should never 167 // happen, don't overwrite past the end of the buffer. 168 if (m_reg_data.GetByteSize() < reg_info->byte_offset + reg_info->byte_size) 169 return false; 170 171 // Grab a pointer to where we are going to put this register 172 uint8_t *dst = const_cast<uint8_t *>( 173 m_reg_data.PeekData(reg_info->byte_offset, reg_info->byte_size)); 174 175 if (dst == nullptr) 176 return false; 177 178 if (data.CopyByteOrderedData(0, // src offset 179 reg_info->byte_size, // src length 180 dst, // dst 181 reg_info->byte_size, // dst length 182 m_reg_data.GetByteOrder())) // dst byte order 183 { 184 SetRegisterIsValid(reg, true); 185 return true; 186 } 187 return false; 188 } 189 190 // Helper function for GDBRemoteRegisterContext::ReadRegisterBytes(). 191 bool GDBRemoteRegisterContext::GetPrimordialRegister( 192 const RegisterInfo *reg_info, GDBRemoteCommunicationClient &gdb_comm) { 193 const uint32_t lldb_reg = reg_info->kinds[eRegisterKindLLDB]; 194 const uint32_t remote_reg = reg_info->kinds[eRegisterKindProcessPlugin]; 195 196 if (DataBufferSP buffer_sp = 197 gdb_comm.ReadRegister(m_thread.GetProtocolID(), remote_reg)) 198 return PrivateSetRegisterValue( 199 lldb_reg, llvm::ArrayRef<uint8_t>(buffer_sp->GetBytes(), 200 buffer_sp->GetByteSize())); 201 return false; 202 } 203 204 bool GDBRemoteRegisterContext::ReadRegisterBytes(const RegisterInfo *reg_info) { 205 ExecutionContext exe_ctx(CalculateThread()); 206 207 Process *process = exe_ctx.GetProcessPtr(); 208 Thread *thread = exe_ctx.GetThreadPtr(); 209 if (process == nullptr || thread == nullptr) 210 return false; 211 212 GDBRemoteCommunicationClient &gdb_comm( 213 ((ProcessGDBRemote *)process)->GetGDBRemote()); 214 215 InvalidateIfNeeded(false); 216 217 const uint32_t reg = reg_info->kinds[eRegisterKindLLDB]; 218 219 if (!GetRegisterIsValid(reg)) { 220 if (m_read_all_at_once && !m_gpacket_cached) { 221 if (DataBufferSP buffer_sp = 222 gdb_comm.ReadAllRegisters(m_thread.GetProtocolID())) { 223 memcpy(const_cast<uint8_t *>(m_reg_data.GetDataStart()), 224 buffer_sp->GetBytes(), 225 std::min(buffer_sp->GetByteSize(), m_reg_data.GetByteSize())); 226 if (buffer_sp->GetByteSize() >= m_reg_data.GetByteSize()) { 227 SetAllRegisterValid(true); 228 return true; 229 } else if (buffer_sp->GetByteSize() > 0) { 230 for (auto x : llvm::enumerate(m_reg_info_sp->registers())) { 231 const struct RegisterInfo ®info = x.value(); 232 m_reg_valid[x.index()] = 233 (reginfo.byte_offset + reginfo.byte_size <= 234 buffer_sp->GetByteSize()); 235 } 236 237 m_gpacket_cached = true; 238 if (GetRegisterIsValid(reg)) 239 return true; 240 } else { 241 Log *log(GetLog(GDBRLog::Thread | GDBRLog::Packets)); 242 LLDB_LOGF( 243 log, 244 "error: GDBRemoteRegisterContext::ReadRegisterBytes tried " 245 "to read the " 246 "entire register context at once, expected at least %" PRId64 247 " bytes " 248 "but only got %" PRId64 " bytes.", 249 m_reg_data.GetByteSize(), buffer_sp->GetByteSize()); 250 return false; 251 } 252 } 253 } 254 if (reg_info->value_regs) { 255 // Process this composite register request by delegating to the 256 // constituent primordial registers. 257 258 // Index of the primordial register. 259 bool success = true; 260 for (uint32_t idx = 0; success; ++idx) { 261 const uint32_t prim_reg = reg_info->value_regs[idx]; 262 if (prim_reg == LLDB_INVALID_REGNUM) 263 break; 264 // We have a valid primordial register as our constituent. Grab the 265 // corresponding register info. 266 const RegisterInfo *prim_reg_info = 267 GetRegisterInfo(eRegisterKindLLDB, prim_reg); 268 if (prim_reg_info == nullptr) 269 success = false; 270 else { 271 // Read the containing register if it hasn't already been read 272 if (!GetRegisterIsValid(prim_reg)) 273 success = GetPrimordialRegister(prim_reg_info, gdb_comm); 274 } 275 } 276 277 if (success) { 278 // If we reach this point, all primordial register requests have 279 // succeeded. Validate this composite register. 280 SetRegisterIsValid(reg_info, true); 281 } 282 } else { 283 // Get each register individually 284 GetPrimordialRegister(reg_info, gdb_comm); 285 } 286 287 // Make sure we got a valid register value after reading it 288 if (!GetRegisterIsValid(reg)) 289 return false; 290 } 291 292 return true; 293 } 294 295 bool GDBRemoteRegisterContext::WriteRegister(const RegisterInfo *reg_info, 296 const RegisterValue &value) { 297 DataExtractor data; 298 if (value.GetData(data)) { 299 if (reg_info->value_regs && 300 reg_info->value_regs[0] != LLDB_INVALID_REGNUM && 301 reg_info->value_regs[1] != LLDB_INVALID_REGNUM) { 302 uint32_t combined_size = 0; 303 for (int i = 0; reg_info->value_regs[i] != LLDB_INVALID_REGNUM; i++) { 304 const RegisterInfo *parent_reg = GetRegisterInfo( 305 eRegisterKindLLDB, reg_info->value_regs[i]); 306 if (!parent_reg) 307 return false; 308 combined_size += parent_reg->byte_size; 309 } 310 311 if (data.GetByteSize() < combined_size) 312 return false; 313 314 uint32_t offset = 0; 315 for (int i = 0; reg_info->value_regs[i] != LLDB_INVALID_REGNUM; i++) { 316 const RegisterInfo *parent_reg = GetRegisterInfo( 317 eRegisterKindLLDB, reg_info->value_regs[i]); 318 assert(parent_reg); 319 320 DataExtractor parent_data{data, offset, parent_reg->byte_size}; 321 if (!WriteRegisterBytes(parent_reg, parent_data, 0)) 322 return false; 323 offset += parent_reg->byte_size; 324 } 325 assert(offset == combined_size); 326 return true; 327 } else 328 return WriteRegisterBytes(reg_info, data, 0); 329 } 330 return false; 331 } 332 333 // Helper function for GDBRemoteRegisterContext::WriteRegisterBytes(). 334 bool GDBRemoteRegisterContext::SetPrimordialRegister( 335 const RegisterInfo *reg_info, GDBRemoteCommunicationClient &gdb_comm) { 336 StreamString packet; 337 StringExtractorGDBRemote response; 338 const uint32_t reg = reg_info->kinds[eRegisterKindLLDB]; 339 // Invalidate just this register 340 SetRegisterIsValid(reg, false); 341 342 return gdb_comm.WriteRegister( 343 m_thread.GetProtocolID(), reg_info->kinds[eRegisterKindProcessPlugin], 344 {m_reg_data.PeekData(reg_info->byte_offset, reg_info->byte_size), 345 reg_info->byte_size}); 346 } 347 348 bool GDBRemoteRegisterContext::WriteRegisterBytes(const RegisterInfo *reg_info, 349 DataExtractor &data, 350 uint32_t data_offset) { 351 ExecutionContext exe_ctx(CalculateThread()); 352 353 Process *process = exe_ctx.GetProcessPtr(); 354 Thread *thread = exe_ctx.GetThreadPtr(); 355 if (process == nullptr || thread == nullptr) 356 return false; 357 358 GDBRemoteCommunicationClient &gdb_comm( 359 ((ProcessGDBRemote *)process)->GetGDBRemote()); 360 361 assert(m_reg_data.GetByteSize() >= 362 reg_info->byte_offset + reg_info->byte_size); 363 364 // If our register context and our register info disagree, which should never 365 // happen, don't overwrite past the end of the buffer. 366 if (m_reg_data.GetByteSize() < reg_info->byte_offset + reg_info->byte_size) 367 return false; 368 369 // Grab a pointer to where we are going to put this register 370 uint8_t *dst = const_cast<uint8_t *>( 371 m_reg_data.PeekData(reg_info->byte_offset, reg_info->byte_size)); 372 373 if (dst == nullptr) 374 return false; 375 376 // Code below is specific to AArch64 target in SVE or SME state 377 // If vector granule (vg) register is being written then thread's 378 // register context reconfiguration is triggered on success. 379 // We do not allow writes to SVG so it is not mentioned here. 380 const ArchSpec &arch = process->GetTarget().GetArchitecture(); 381 bool do_reconfigure_arm64_sve = arch.IsValid() && 382 arch.GetTriple().isAArch64() && 383 (strcmp(reg_info->name, "vg") == 0); 384 385 if (data.CopyByteOrderedData(data_offset, // src offset 386 reg_info->byte_size, // src length 387 dst, // dst 388 reg_info->byte_size, // dst length 389 m_reg_data.GetByteOrder())) // dst byte order 390 { 391 GDBRemoteClientBase::Lock lock(gdb_comm); 392 if (lock) { 393 if (m_write_all_at_once) { 394 // Invalidate all register values 395 InvalidateIfNeeded(true); 396 397 // Set all registers in one packet 398 if (gdb_comm.WriteAllRegisters( 399 m_thread.GetProtocolID(), 400 {m_reg_data.GetDataStart(), size_t(m_reg_data.GetByteSize())})) 401 402 { 403 if (do_reconfigure_arm64_sve) 404 AArch64Reconfigure(); 405 406 InvalidateAllRegisters(); 407 408 return true; 409 } 410 } else { 411 bool success = true; 412 413 if (reg_info->value_regs) { 414 // This register is part of another register. In this case we read 415 // the actual register data for any "value_regs", and once all that 416 // data is read, we will have enough data in our register context 417 // bytes for the value of this register 418 419 // Invalidate this composite register first. 420 421 for (uint32_t idx = 0; success; ++idx) { 422 const uint32_t reg = reg_info->value_regs[idx]; 423 if (reg == LLDB_INVALID_REGNUM) 424 break; 425 // We have a valid primordial register as our constituent. Grab the 426 // corresponding register info. 427 const RegisterInfo *value_reg_info = 428 GetRegisterInfo(eRegisterKindLLDB, reg); 429 if (value_reg_info == nullptr) 430 success = false; 431 else 432 success = SetPrimordialRegister(value_reg_info, gdb_comm); 433 } 434 } else { 435 // This is an actual register, write it 436 success = SetPrimordialRegister(reg_info, gdb_comm); 437 438 if (success && do_reconfigure_arm64_sve) { 439 AArch64Reconfigure(); 440 InvalidateAllRegisters(); 441 } 442 } 443 444 // Check if writing this register will invalidate any other register 445 // values? If so, invalidate them 446 if (reg_info->invalidate_regs) { 447 for (uint32_t idx = 0, reg = reg_info->invalidate_regs[0]; 448 reg != LLDB_INVALID_REGNUM; 449 reg = reg_info->invalidate_regs[++idx]) 450 SetRegisterIsValid(ConvertRegisterKindToRegisterNumber( 451 eRegisterKindLLDB, reg), 452 false); 453 } 454 455 return success; 456 } 457 } else { 458 Log *log(GetLog(GDBRLog::Thread | GDBRLog::Packets)); 459 if (log) { 460 if (log->GetVerbose()) { 461 StreamString strm; 462 process->DumpPluginHistory(strm); 463 LLDB_LOGF(log, 464 "error: failed to get packet sequence mutex, not sending " 465 "write register for \"%s\":\n%s", 466 reg_info->name, strm.GetData()); 467 } else 468 LLDB_LOGF(log, 469 "error: failed to get packet sequence mutex, not sending " 470 "write register for \"%s\"", 471 reg_info->name); 472 } 473 } 474 } 475 return false; 476 } 477 478 bool GDBRemoteRegisterContext::ReadAllRegisterValues( 479 RegisterCheckpoint ®_checkpoint) { 480 ExecutionContext exe_ctx(CalculateThread()); 481 482 Process *process = exe_ctx.GetProcessPtr(); 483 Thread *thread = exe_ctx.GetThreadPtr(); 484 if (process == nullptr || thread == nullptr) 485 return false; 486 487 GDBRemoteCommunicationClient &gdb_comm( 488 ((ProcessGDBRemote *)process)->GetGDBRemote()); 489 490 uint32_t save_id = 0; 491 if (gdb_comm.SaveRegisterState(thread->GetProtocolID(), save_id)) { 492 reg_checkpoint.SetID(save_id); 493 reg_checkpoint.GetData().reset(); 494 return true; 495 } else { 496 reg_checkpoint.SetID(0); // Invalid save ID is zero 497 return ReadAllRegisterValues(reg_checkpoint.GetData()); 498 } 499 } 500 501 bool GDBRemoteRegisterContext::WriteAllRegisterValues( 502 const RegisterCheckpoint ®_checkpoint) { 503 uint32_t save_id = reg_checkpoint.GetID(); 504 if (save_id != 0) { 505 ExecutionContext exe_ctx(CalculateThread()); 506 507 Process *process = exe_ctx.GetProcessPtr(); 508 Thread *thread = exe_ctx.GetThreadPtr(); 509 if (process == nullptr || thread == nullptr) 510 return false; 511 512 GDBRemoteCommunicationClient &gdb_comm( 513 ((ProcessGDBRemote *)process)->GetGDBRemote()); 514 515 return gdb_comm.RestoreRegisterState(m_thread.GetProtocolID(), save_id); 516 } else { 517 return WriteAllRegisterValues(reg_checkpoint.GetData()); 518 } 519 } 520 521 bool GDBRemoteRegisterContext::ReadAllRegisterValues( 522 lldb::WritableDataBufferSP &data_sp) { 523 ExecutionContext exe_ctx(CalculateThread()); 524 525 Process *process = exe_ctx.GetProcessPtr(); 526 Thread *thread = exe_ctx.GetThreadPtr(); 527 if (process == nullptr || thread == nullptr) 528 return false; 529 530 GDBRemoteCommunicationClient &gdb_comm( 531 ((ProcessGDBRemote *)process)->GetGDBRemote()); 532 533 const bool use_g_packet = 534 !gdb_comm.AvoidGPackets((ProcessGDBRemote *)process); 535 536 GDBRemoteClientBase::Lock lock(gdb_comm); 537 if (lock) { 538 if (gdb_comm.SyncThreadState(m_thread.GetProtocolID())) 539 InvalidateAllRegisters(); 540 541 if (use_g_packet) { 542 if (DataBufferSP data_buffer = 543 gdb_comm.ReadAllRegisters(m_thread.GetProtocolID())) { 544 data_sp = std::make_shared<DataBufferHeap>(*data_buffer); 545 return true; 546 } 547 } 548 549 // We're going to read each register 550 // individually and store them as binary data in a buffer. 551 const RegisterInfo *reg_info; 552 553 for (uint32_t i = 0; (reg_info = GetRegisterInfoAtIndex(i)) != nullptr; 554 i++) { 555 if (reg_info 556 ->value_regs) // skip registers that are slices of real registers 557 continue; 558 ReadRegisterBytes(reg_info); 559 // ReadRegisterBytes saves the contents of the register in to the 560 // m_reg_data buffer 561 } 562 data_sp = std::make_shared<DataBufferHeap>( 563 m_reg_data.GetDataStart(), m_reg_info_sp->GetRegisterDataByteSize()); 564 return true; 565 } else { 566 567 Log *log(GetLog(GDBRLog::Thread | GDBRLog::Packets)); 568 if (log) { 569 if (log->GetVerbose()) { 570 StreamString strm; 571 process->DumpPluginHistory(strm); 572 LLDB_LOGF(log, 573 "error: failed to get packet sequence mutex, not sending " 574 "read all registers:\n%s", 575 strm.GetData()); 576 } else 577 LLDB_LOGF(log, 578 "error: failed to get packet sequence mutex, not sending " 579 "read all registers"); 580 } 581 } 582 583 data_sp.reset(); 584 return false; 585 } 586 587 bool GDBRemoteRegisterContext::WriteAllRegisterValues( 588 const lldb::DataBufferSP &data_sp) { 589 if (!data_sp || data_sp->GetBytes() == nullptr || data_sp->GetByteSize() == 0) 590 return false; 591 592 ExecutionContext exe_ctx(CalculateThread()); 593 594 Process *process = exe_ctx.GetProcessPtr(); 595 Thread *thread = exe_ctx.GetThreadPtr(); 596 if (process == nullptr || thread == nullptr) 597 return false; 598 599 GDBRemoteCommunicationClient &gdb_comm( 600 ((ProcessGDBRemote *)process)->GetGDBRemote()); 601 602 const bool use_g_packet = 603 !gdb_comm.AvoidGPackets((ProcessGDBRemote *)process); 604 605 GDBRemoteClientBase::Lock lock(gdb_comm); 606 if (lock) { 607 // The data_sp contains the G response packet. 608 if (use_g_packet) { 609 if (gdb_comm.WriteAllRegisters( 610 m_thread.GetProtocolID(), 611 {data_sp->GetBytes(), size_t(data_sp->GetByteSize())})) 612 return true; 613 614 uint32_t num_restored = 0; 615 // We need to manually go through all of the registers and restore them 616 // manually 617 DataExtractor restore_data(data_sp, m_reg_data.GetByteOrder(), 618 m_reg_data.GetAddressByteSize()); 619 620 const RegisterInfo *reg_info; 621 622 // The g packet contents may either include the slice registers 623 // (registers defined in terms of other registers, e.g. eax is a subset 624 // of rax) or not. The slice registers should NOT be in the g packet, 625 // but some implementations may incorrectly include them. 626 // 627 // If the slice registers are included in the packet, we must step over 628 // the slice registers when parsing the packet -- relying on the 629 // RegisterInfo byte_offset field would be incorrect. If the slice 630 // registers are not included, then using the byte_offset values into the 631 // data buffer is the best way to find individual register values. 632 633 uint64_t size_including_slice_registers = 0; 634 uint64_t size_not_including_slice_registers = 0; 635 uint64_t size_by_highest_offset = 0; 636 637 for (uint32_t reg_idx = 0; 638 (reg_info = GetRegisterInfoAtIndex(reg_idx)) != nullptr; ++reg_idx) { 639 size_including_slice_registers += reg_info->byte_size; 640 if (reg_info->value_regs == nullptr) 641 size_not_including_slice_registers += reg_info->byte_size; 642 if (reg_info->byte_offset >= size_by_highest_offset) 643 size_by_highest_offset = reg_info->byte_offset + reg_info->byte_size; 644 } 645 646 bool use_byte_offset_into_buffer; 647 if (size_by_highest_offset == restore_data.GetByteSize()) { 648 // The size of the packet agrees with the highest offset: + size in the 649 // register file 650 use_byte_offset_into_buffer = true; 651 } else if (size_not_including_slice_registers == 652 restore_data.GetByteSize()) { 653 // The size of the packet is the same as concatenating all of the 654 // registers sequentially, skipping the slice registers 655 use_byte_offset_into_buffer = true; 656 } else if (size_including_slice_registers == restore_data.GetByteSize()) { 657 // The slice registers are present in the packet (when they shouldn't 658 // be). Don't try to use the RegisterInfo byte_offset into the 659 // restore_data, it will point to the wrong place. 660 use_byte_offset_into_buffer = false; 661 } else { 662 // None of our expected sizes match the actual g packet data we're 663 // looking at. The most conservative approach here is to use the 664 // running total byte offset. 665 use_byte_offset_into_buffer = false; 666 } 667 668 // In case our register definitions don't include the correct offsets, 669 // keep track of the size of each reg & compute offset based on that. 670 uint32_t running_byte_offset = 0; 671 for (uint32_t reg_idx = 0; 672 (reg_info = GetRegisterInfoAtIndex(reg_idx)) != nullptr; 673 ++reg_idx, running_byte_offset += reg_info->byte_size) { 674 // Skip composite aka slice registers (e.g. eax is a slice of rax). 675 if (reg_info->value_regs) 676 continue; 677 678 const uint32_t reg = reg_info->kinds[eRegisterKindLLDB]; 679 680 uint32_t register_offset; 681 if (use_byte_offset_into_buffer) { 682 register_offset = reg_info->byte_offset; 683 } else { 684 register_offset = running_byte_offset; 685 } 686 687 const uint32_t reg_byte_size = reg_info->byte_size; 688 689 const uint8_t *restore_src = 690 restore_data.PeekData(register_offset, reg_byte_size); 691 if (restore_src) { 692 SetRegisterIsValid(reg, false); 693 if (gdb_comm.WriteRegister( 694 m_thread.GetProtocolID(), 695 reg_info->kinds[eRegisterKindProcessPlugin], 696 {restore_src, reg_byte_size})) 697 ++num_restored; 698 } 699 } 700 return num_restored > 0; 701 } else { 702 // For the use_g_packet == false case, we're going to write each register 703 // individually. The data buffer is binary data in this case, instead of 704 // ascii characters. 705 706 bool arm64_debugserver = false; 707 if (m_thread.GetProcess().get()) { 708 const ArchSpec &arch = 709 m_thread.GetProcess()->GetTarget().GetArchitecture(); 710 if (arch.IsValid() && (arch.GetMachine() == llvm::Triple::aarch64 || 711 arch.GetMachine() == llvm::Triple::aarch64_32) && 712 arch.GetTriple().getVendor() == llvm::Triple::Apple && 713 arch.GetTriple().getOS() == llvm::Triple::IOS) { 714 arm64_debugserver = true; 715 } 716 } 717 uint32_t num_restored = 0; 718 const RegisterInfo *reg_info; 719 for (uint32_t i = 0; (reg_info = GetRegisterInfoAtIndex(i)) != nullptr; 720 i++) { 721 if (reg_info->value_regs) // skip registers that are slices of real 722 // registers 723 continue; 724 // Skip the fpsr and fpcr floating point status/control register 725 // writing to work around a bug in an older version of debugserver that 726 // would lead to register context corruption when writing fpsr/fpcr. 727 if (arm64_debugserver && (strcmp(reg_info->name, "fpsr") == 0 || 728 strcmp(reg_info->name, "fpcr") == 0)) { 729 continue; 730 } 731 732 SetRegisterIsValid(reg_info, false); 733 if (gdb_comm.WriteRegister(m_thread.GetProtocolID(), 734 reg_info->kinds[eRegisterKindProcessPlugin], 735 {data_sp->GetBytes() + reg_info->byte_offset, 736 reg_info->byte_size})) 737 ++num_restored; 738 } 739 return num_restored > 0; 740 } 741 } else { 742 Log *log(GetLog(GDBRLog::Thread | GDBRLog::Packets)); 743 if (log) { 744 if (log->GetVerbose()) { 745 StreamString strm; 746 process->DumpPluginHistory(strm); 747 LLDB_LOGF(log, 748 "error: failed to get packet sequence mutex, not sending " 749 "write all registers:\n%s", 750 strm.GetData()); 751 } else 752 LLDB_LOGF(log, 753 "error: failed to get packet sequence mutex, not sending " 754 "write all registers"); 755 } 756 } 757 return false; 758 } 759 760 uint32_t GDBRemoteRegisterContext::ConvertRegisterKindToRegisterNumber( 761 lldb::RegisterKind kind, uint32_t num) { 762 return m_reg_info_sp->ConvertRegisterKindToRegisterNumber(kind, num); 763 } 764 765 void GDBRemoteRegisterContext::AArch64Reconfigure() { 766 assert(m_reg_info_sp); 767 768 // Once we start to reconfigure registers, we cannot read any of them. 769 // So we must read VG and SVG up front. 770 771 const uint64_t fail_value = LLDB_INVALID_ADDRESS; 772 std::optional<uint64_t> vg_reg_value; 773 const RegisterInfo *vg_reg_info = m_reg_info_sp->GetRegisterInfo("vg"); 774 if (vg_reg_info) { 775 // Make sure we get the latest value of vg from the remote. 776 SetRegisterIsValid(vg_reg_info, false); 777 uint32_t vg_reg_num = vg_reg_info->kinds[eRegisterKindLLDB]; 778 uint64_t reg_value = ReadRegisterAsUnsigned(vg_reg_num, fail_value); 779 if (reg_value != fail_value && reg_value <= 32) 780 vg_reg_value = reg_value; 781 } 782 783 std::optional<uint64_t> svg_reg_value; 784 const RegisterInfo *svg_reg_info = m_reg_info_sp->GetRegisterInfo("svg"); 785 if (svg_reg_info) { 786 uint32_t svg_reg_num = svg_reg_info->kinds[eRegisterKindLLDB]; 787 uint64_t reg_value = ReadRegisterAsUnsigned(svg_reg_num, fail_value); 788 if (reg_value != fail_value && reg_value <= 32) 789 svg_reg_value = reg_value; 790 } 791 792 if (vg_reg_value) 793 m_reg_info_sp->UpdateARM64SVERegistersInfos(*vg_reg_value); 794 if (svg_reg_value) 795 m_reg_info_sp->UpdateARM64SMERegistersInfos(*svg_reg_value); 796 797 // At this point if we have updated any registers, their offsets will all be 798 // invalid. If we did, we need to update them all. 799 if (vg_reg_value || svg_reg_value) { 800 m_reg_info_sp->ConfigureOffsets(); 801 // From here we are able to read registers again. 802 803 // Make a heap based buffer that is big enough to store all registers 804 m_reg_data.SetData(std::make_shared<DataBufferHeap>( 805 m_reg_info_sp->GetRegisterDataByteSize(), 0)); 806 m_reg_data.SetByteOrder(GetByteOrder()); 807 } 808 } 809 810 void GDBRemoteDynamicRegisterInfo::UpdateARM64SVERegistersInfos(uint64_t vg) { 811 // SVE Z register size is vg x 8 bytes. 812 uint32_t z_reg_byte_size = vg * 8; 813 814 // SVE vector length has changed, accordingly set size of Z, P and FFR 815 // registers. Also invalidate register offsets it will be recalculated 816 // after SVE register size update. 817 for (auto ® : m_regs) { 818 if (reg.value_regs == nullptr) { 819 if (reg.name[0] == 'z' && isdigit(reg.name[1])) 820 reg.byte_size = z_reg_byte_size; 821 else if (reg.name[0] == 'p' && isdigit(reg.name[1])) 822 reg.byte_size = vg; 823 else if (strcmp(reg.name, "ffr") == 0) 824 reg.byte_size = vg; 825 } 826 reg.byte_offset = LLDB_INVALID_INDEX32; 827 } 828 } 829 830 void GDBRemoteDynamicRegisterInfo::UpdateARM64SMERegistersInfos(uint64_t svg) { 831 for (auto ® : m_regs) { 832 if (strcmp(reg.name, "za") == 0) { 833 // ZA is a register with size (svg*8) * (svg*8). A square essentially. 834 reg.byte_size = (svg * 8) * (svg * 8); 835 } 836 reg.byte_offset = LLDB_INVALID_INDEX32; 837 } 838 } 839