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 state 377 // If vector granule (vg) register is being written then thread's 378 // register context reconfiguration is triggered on success. 379 bool do_reconfigure_arm64_sve = false; 380 const ArchSpec &arch = process->GetTarget().GetArchitecture(); 381 if (arch.IsValid() && arch.GetTriple().isAArch64()) 382 if (strcmp(reg_info->name, "vg") == 0) 383 do_reconfigure_arm64_sve = true; 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 SetAllRegisterValid(false); 404 405 if (do_reconfigure_arm64_sve) 406 AArch64SVEReconfigure(); 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 AArch64SVEReconfigure(); 440 } 441 442 // Check if writing this register will invalidate any other register 443 // values? If so, invalidate them 444 if (reg_info->invalidate_regs) { 445 for (uint32_t idx = 0, reg = reg_info->invalidate_regs[0]; 446 reg != LLDB_INVALID_REGNUM; 447 reg = reg_info->invalidate_regs[++idx]) 448 SetRegisterIsValid(ConvertRegisterKindToRegisterNumber( 449 eRegisterKindLLDB, reg), 450 false); 451 } 452 453 return success; 454 } 455 } else { 456 Log *log(GetLog(GDBRLog::Thread | GDBRLog::Packets)); 457 if (log) { 458 if (log->GetVerbose()) { 459 StreamString strm; 460 gdb_comm.DumpHistory(strm); 461 LLDB_LOGF(log, 462 "error: failed to get packet sequence mutex, not sending " 463 "write register for \"%s\":\n%s", 464 reg_info->name, strm.GetData()); 465 } else 466 LLDB_LOGF(log, 467 "error: failed to get packet sequence mutex, not sending " 468 "write register for \"%s\"", 469 reg_info->name); 470 } 471 } 472 } 473 return false; 474 } 475 476 bool GDBRemoteRegisterContext::ReadAllRegisterValues( 477 RegisterCheckpoint ®_checkpoint) { 478 ExecutionContext exe_ctx(CalculateThread()); 479 480 Process *process = exe_ctx.GetProcessPtr(); 481 Thread *thread = exe_ctx.GetThreadPtr(); 482 if (process == nullptr || thread == nullptr) 483 return false; 484 485 GDBRemoteCommunicationClient &gdb_comm( 486 ((ProcessGDBRemote *)process)->GetGDBRemote()); 487 488 uint32_t save_id = 0; 489 if (gdb_comm.SaveRegisterState(thread->GetProtocolID(), save_id)) { 490 reg_checkpoint.SetID(save_id); 491 reg_checkpoint.GetData().reset(); 492 return true; 493 } else { 494 reg_checkpoint.SetID(0); // Invalid save ID is zero 495 return ReadAllRegisterValues(reg_checkpoint.GetData()); 496 } 497 } 498 499 bool GDBRemoteRegisterContext::WriteAllRegisterValues( 500 const RegisterCheckpoint ®_checkpoint) { 501 uint32_t save_id = reg_checkpoint.GetID(); 502 if (save_id != 0) { 503 ExecutionContext exe_ctx(CalculateThread()); 504 505 Process *process = exe_ctx.GetProcessPtr(); 506 Thread *thread = exe_ctx.GetThreadPtr(); 507 if (process == nullptr || thread == nullptr) 508 return false; 509 510 GDBRemoteCommunicationClient &gdb_comm( 511 ((ProcessGDBRemote *)process)->GetGDBRemote()); 512 513 return gdb_comm.RestoreRegisterState(m_thread.GetProtocolID(), save_id); 514 } else { 515 return WriteAllRegisterValues(reg_checkpoint.GetData()); 516 } 517 } 518 519 bool GDBRemoteRegisterContext::ReadAllRegisterValues( 520 lldb::DataBufferSP &data_sp) { 521 ExecutionContext exe_ctx(CalculateThread()); 522 523 Process *process = exe_ctx.GetProcessPtr(); 524 Thread *thread = exe_ctx.GetThreadPtr(); 525 if (process == nullptr || thread == nullptr) 526 return false; 527 528 GDBRemoteCommunicationClient &gdb_comm( 529 ((ProcessGDBRemote *)process)->GetGDBRemote()); 530 531 const bool use_g_packet = 532 !gdb_comm.AvoidGPackets((ProcessGDBRemote *)process); 533 534 GDBRemoteClientBase::Lock lock(gdb_comm); 535 if (lock) { 536 if (gdb_comm.SyncThreadState(m_thread.GetProtocolID())) 537 InvalidateAllRegisters(); 538 539 if (use_g_packet && 540 (data_sp = gdb_comm.ReadAllRegisters(m_thread.GetProtocolID()))) 541 return true; 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 gdb_comm.DumpHistory(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 gdb_comm.DumpHistory(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::AArch64SVEReconfigure() { 760 if (!m_reg_info_sp) 761 return false; 762 763 const RegisterInfo *reg_info = m_reg_info_sp->GetRegisterInfo("vg"); 764 if (!reg_info) 765 return false; 766 767 uint64_t fail_value = LLDB_INVALID_ADDRESS; 768 uint32_t vg_reg_num = reg_info->kinds[eRegisterKindLLDB]; 769 uint64_t vg_reg_value = ReadRegisterAsUnsigned(vg_reg_num, fail_value); 770 771 if (vg_reg_value != fail_value && vg_reg_value <= 32) { 772 const RegisterInfo *reg_info = m_reg_info_sp->GetRegisterInfo("p0"); 773 if (!reg_info || vg_reg_value == reg_info->byte_size) 774 return false; 775 776 if (m_reg_info_sp->UpdateARM64SVERegistersInfos(vg_reg_value)) { 777 // Make a heap based buffer that is big enough to store all registers 778 m_reg_data.SetData(std::make_shared<DataBufferHeap>( 779 m_reg_info_sp->GetRegisterDataByteSize(), 0)); 780 m_reg_data.SetByteOrder(GetByteOrder()); 781 782 InvalidateAllRegisters(); 783 784 return true; 785 } 786 } 787 788 return false; 789 } 790 791 bool GDBRemoteDynamicRegisterInfo::UpdateARM64SVERegistersInfos(uint64_t vg) { 792 // SVE Z register size is vg x 8 bytes. 793 uint32_t z_reg_byte_size = vg * 8; 794 795 // SVE vector length has changed, accordingly set size of Z, P and FFR 796 // registers. Also invalidate register offsets it will be recalculated 797 // after SVE register size update. 798 for (auto ® : m_regs) { 799 if (reg.value_regs == nullptr) { 800 if (reg.name[0] == 'z' && isdigit(reg.name[1])) 801 reg.byte_size = z_reg_byte_size; 802 else if (reg.name[0] == 'p' && isdigit(reg.name[1])) 803 reg.byte_size = vg; 804 else if (strcmp(reg.name, "ffr") == 0) 805 reg.byte_size = vg; 806 } 807 reg.byte_offset = LLDB_INVALID_INDEX32; 808 } 809 810 // Re-calculate register offsets 811 ConfigureOffsets(); 812 return true; 813 } 814