1 //===-- UnwindAssemblyInstEmulation.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 "UnwindAssemblyInstEmulation.h" 10 11 #include "lldb/Core/Address.h" 12 #include "lldb/Core/Disassembler.h" 13 #include "lldb/Core/DumpDataExtractor.h" 14 #include "lldb/Core/DumpRegisterValue.h" 15 #include "lldb/Core/FormatEntity.h" 16 #include "lldb/Core/PluginManager.h" 17 #include "lldb/Target/ExecutionContext.h" 18 #include "lldb/Target/Process.h" 19 #include "lldb/Target/Target.h" 20 #include "lldb/Target/Thread.h" 21 #include "lldb/Utility/ArchSpec.h" 22 #include "lldb/Utility/DataBufferHeap.h" 23 #include "lldb/Utility/DataExtractor.h" 24 #include "lldb/Utility/Log.h" 25 #include "lldb/Utility/Status.h" 26 #include "lldb/Utility/StreamString.h" 27 28 using namespace lldb; 29 using namespace lldb_private; 30 31 LLDB_PLUGIN_DEFINE(UnwindAssemblyInstEmulation) 32 33 // UnwindAssemblyInstEmulation method definitions 34 35 bool UnwindAssemblyInstEmulation::GetNonCallSiteUnwindPlanFromAssembly( 36 AddressRange &range, Thread &thread, UnwindPlan &unwind_plan) { 37 std::vector<uint8_t> function_text(range.GetByteSize()); 38 ProcessSP process_sp(thread.GetProcess()); 39 if (process_sp) { 40 Status error; 41 const bool prefer_file_cache = true; 42 if (process_sp->GetTarget().ReadMemory( 43 range.GetBaseAddress(), prefer_file_cache, function_text.data(), 44 range.GetByteSize(), error) != range.GetByteSize()) { 45 return false; 46 } 47 } 48 return GetNonCallSiteUnwindPlanFromAssembly( 49 range, function_text.data(), function_text.size(), unwind_plan); 50 } 51 52 bool UnwindAssemblyInstEmulation::GetNonCallSiteUnwindPlanFromAssembly( 53 AddressRange &range, uint8_t *opcode_data, size_t opcode_size, 54 UnwindPlan &unwind_plan) { 55 if (opcode_data == nullptr || opcode_size == 0) 56 return false; 57 58 if (range.GetByteSize() > 0 && range.GetBaseAddress().IsValid() && 59 m_inst_emulator_up.get()) { 60 61 // The instruction emulation subclass setup the unwind plan for the first 62 // instruction. 63 m_inst_emulator_up->CreateFunctionEntryUnwind(unwind_plan); 64 65 // CreateFunctionEntryUnwind should have created the first row. If it 66 // doesn't, then we are done. 67 if (unwind_plan.GetRowCount() == 0) 68 return false; 69 70 const bool prefer_file_cache = true; 71 DisassemblerSP disasm_sp(Disassembler::DisassembleBytes( 72 m_arch, nullptr, nullptr, range.GetBaseAddress(), opcode_data, 73 opcode_size, 99999, prefer_file_cache)); 74 75 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_UNWIND)); 76 77 if (disasm_sp) { 78 79 m_range_ptr = ⦥ 80 m_unwind_plan_ptr = &unwind_plan; 81 82 const uint32_t addr_byte_size = m_arch.GetAddressByteSize(); 83 const bool show_address = true; 84 const bool show_bytes = true; 85 m_inst_emulator_up->GetRegisterInfo(unwind_plan.GetRegisterKind(), 86 unwind_plan.GetInitialCFARegister(), 87 m_cfa_reg_info); 88 89 m_fp_is_cfa = false; 90 m_register_values.clear(); 91 m_pushed_regs.clear(); 92 93 // Initialize the CFA with a known value. In the 32 bit case it will be 94 // 0x80000000, and in the 64 bit case 0x8000000000000000. We use the 95 // address byte size to be safe for any future address sizes 96 m_initial_sp = (1ull << ((addr_byte_size * 8) - 1)); 97 RegisterValue cfa_reg_value; 98 cfa_reg_value.SetUInt(m_initial_sp, m_cfa_reg_info.byte_size); 99 SetRegisterValue(m_cfa_reg_info, cfa_reg_value); 100 101 const InstructionList &inst_list = disasm_sp->GetInstructionList(); 102 const size_t num_instructions = inst_list.GetSize(); 103 104 if (num_instructions > 0) { 105 Instruction *inst = inst_list.GetInstructionAtIndex(0).get(); 106 const lldb::addr_t base_addr = inst->GetAddress().GetFileAddress(); 107 108 // Map for storing the unwind plan row and the value of the registers 109 // at a given offset. When we see a forward branch we add a new entry 110 // to this map with the actual unwind plan row and register context for 111 // the target address of the branch as the current data have to be 112 // valid for the target address of the branch too if we are in the same 113 // function. 114 std::map<lldb::addr_t, std::pair<UnwindPlan::RowSP, RegisterValueMap>> 115 saved_unwind_states; 116 117 // Make a copy of the current instruction Row and save it in m_curr_row 118 // so we can add updates as we process the instructions. 119 UnwindPlan::RowSP last_row = unwind_plan.GetLastRow(); 120 UnwindPlan::Row *newrow = new UnwindPlan::Row; 121 if (last_row.get()) 122 *newrow = *last_row.get(); 123 m_curr_row.reset(newrow); 124 125 // Add the initial state to the save list with offset 0. 126 saved_unwind_states.insert({0, {last_row, m_register_values}}); 127 128 // cache the pc register number (in whatever register numbering this 129 // UnwindPlan uses) for quick reference during instruction parsing. 130 RegisterInfo pc_reg_info; 131 m_inst_emulator_up->GetRegisterInfo( 132 eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, pc_reg_info); 133 134 // cache the return address register number (in whatever register 135 // numbering this UnwindPlan uses) for quick reference during 136 // instruction parsing. 137 RegisterInfo ra_reg_info; 138 m_inst_emulator_up->GetRegisterInfo( 139 eRegisterKindGeneric, LLDB_REGNUM_GENERIC_RA, ra_reg_info); 140 141 // The architecture dependent condition code of the last processed 142 // instruction. 143 EmulateInstruction::InstructionCondition last_condition = 144 EmulateInstruction::UnconditionalCondition; 145 lldb::addr_t condition_block_start_offset = 0; 146 147 for (size_t idx = 0; idx < num_instructions; ++idx) { 148 m_curr_row_modified = false; 149 m_forward_branch_offset = 0; 150 151 inst = inst_list.GetInstructionAtIndex(idx).get(); 152 if (inst) { 153 lldb::addr_t current_offset = 154 inst->GetAddress().GetFileAddress() - base_addr; 155 auto it = saved_unwind_states.upper_bound(current_offset); 156 assert(it != saved_unwind_states.begin() && 157 "Unwind row for the function entry missing"); 158 --it; // Move it to the row corresponding to the current offset 159 160 // If the offset of m_curr_row don't match with the offset we see 161 // in saved_unwind_states then we have to update m_curr_row and 162 // m_register_values based on the saved values. It is happening 163 // after we processed an epilogue and a return to caller 164 // instruction. 165 if (it->second.first->GetOffset() != m_curr_row->GetOffset()) { 166 UnwindPlan::Row *newrow = new UnwindPlan::Row; 167 *newrow = *it->second.first; 168 m_curr_row.reset(newrow); 169 m_register_values = it->second.second; 170 } 171 172 m_inst_emulator_up->SetInstruction(inst->GetOpcode(), 173 inst->GetAddress(), nullptr); 174 175 if (last_condition != 176 m_inst_emulator_up->GetInstructionCondition()) { 177 if (m_inst_emulator_up->GetInstructionCondition() != 178 EmulateInstruction::UnconditionalCondition && 179 saved_unwind_states.count(current_offset) == 0) { 180 // If we don't have a saved row for the current offset then 181 // save our current state because we will have to restore it 182 // after the conditional block. 183 auto new_row = 184 std::make_shared<UnwindPlan::Row>(*m_curr_row.get()); 185 saved_unwind_states.insert( 186 {current_offset, {new_row, m_register_values}}); 187 } 188 189 // If the last instruction was conditional with a different 190 // condition then the then current condition then restore the 191 // condition. 192 if (last_condition != 193 EmulateInstruction::UnconditionalCondition) { 194 const auto &saved_state = 195 saved_unwind_states.at(condition_block_start_offset); 196 m_curr_row = 197 std::make_shared<UnwindPlan::Row>(*saved_state.first); 198 m_curr_row->SetOffset(current_offset); 199 m_register_values = saved_state.second; 200 bool replace_existing = 201 true; // The last instruction might already 202 // created a row for this offset and 203 // we want to overwrite it. 204 unwind_plan.InsertRow( 205 std::make_shared<UnwindPlan::Row>(*m_curr_row), 206 replace_existing); 207 } 208 209 // We are starting a new conditional block at the actual offset 210 condition_block_start_offset = current_offset; 211 } 212 213 if (log && log->GetVerbose()) { 214 StreamString strm; 215 lldb_private::FormatEntity::Entry format; 216 FormatEntity::Parse("${frame.pc}: ", format); 217 inst->Dump(&strm, inst_list.GetMaxOpcocdeByteSize(), show_address, 218 show_bytes, nullptr, nullptr, nullptr, &format, 0); 219 log->PutString(strm.GetString()); 220 } 221 222 last_condition = m_inst_emulator_up->GetInstructionCondition(); 223 224 m_inst_emulator_up->EvaluateInstruction( 225 eEmulateInstructionOptionIgnoreConditions); 226 227 // If the current instruction is a branch forward then save the 228 // current CFI information for the offset where we are branching. 229 if (m_forward_branch_offset != 0 && 230 range.ContainsFileAddress(inst->GetAddress().GetFileAddress() + 231 m_forward_branch_offset)) { 232 auto newrow = 233 std::make_shared<UnwindPlan::Row>(*m_curr_row.get()); 234 newrow->SetOffset(current_offset + m_forward_branch_offset); 235 saved_unwind_states.insert( 236 {current_offset + m_forward_branch_offset, 237 {newrow, m_register_values}}); 238 unwind_plan.InsertRow(newrow); 239 } 240 241 // Were there any changes to the CFI while evaluating this 242 // instruction? 243 if (m_curr_row_modified) { 244 // Save the modified row if we don't already have a CFI row in 245 // the current address 246 if (saved_unwind_states.count( 247 current_offset + inst->GetOpcode().GetByteSize()) == 0) { 248 m_curr_row->SetOffset(current_offset + 249 inst->GetOpcode().GetByteSize()); 250 unwind_plan.InsertRow(m_curr_row); 251 saved_unwind_states.insert( 252 {current_offset + inst->GetOpcode().GetByteSize(), 253 {m_curr_row, m_register_values}}); 254 255 // Allocate a new Row for m_curr_row, copy the current state 256 // into it 257 UnwindPlan::Row *newrow = new UnwindPlan::Row; 258 *newrow = *m_curr_row.get(); 259 m_curr_row.reset(newrow); 260 } 261 } 262 } 263 } 264 } 265 } 266 267 if (log && log->GetVerbose()) { 268 StreamString strm; 269 lldb::addr_t base_addr = range.GetBaseAddress().GetFileAddress(); 270 strm.Printf("Resulting unwind rows for [0x%" PRIx64 " - 0x%" PRIx64 "):", 271 base_addr, base_addr + range.GetByteSize()); 272 unwind_plan.Dump(strm, nullptr, base_addr); 273 log->PutString(strm.GetString()); 274 } 275 return unwind_plan.GetRowCount() > 0; 276 } 277 return false; 278 } 279 280 bool UnwindAssemblyInstEmulation::AugmentUnwindPlanFromCallSite( 281 AddressRange &func, Thread &thread, UnwindPlan &unwind_plan) { 282 return false; 283 } 284 285 bool UnwindAssemblyInstEmulation::GetFastUnwindPlan(AddressRange &func, 286 Thread &thread, 287 UnwindPlan &unwind_plan) { 288 return false; 289 } 290 291 bool UnwindAssemblyInstEmulation::FirstNonPrologueInsn( 292 AddressRange &func, const ExecutionContext &exe_ctx, 293 Address &first_non_prologue_insn) { 294 return false; 295 } 296 297 UnwindAssembly * 298 UnwindAssemblyInstEmulation::CreateInstance(const ArchSpec &arch) { 299 std::unique_ptr<EmulateInstruction> inst_emulator_up( 300 EmulateInstruction::FindPlugin(arch, eInstructionTypePrologueEpilogue, 301 nullptr)); 302 // Make sure that all prologue instructions are handled 303 if (inst_emulator_up) 304 return new UnwindAssemblyInstEmulation(arch, inst_emulator_up.release()); 305 return nullptr; 306 } 307 308 // PluginInterface protocol in UnwindAssemblyParser_x86 309 ConstString UnwindAssemblyInstEmulation::GetPluginName() { 310 return GetPluginNameStatic(); 311 } 312 313 uint32_t UnwindAssemblyInstEmulation::GetPluginVersion() { return 1; } 314 315 void UnwindAssemblyInstEmulation::Initialize() { 316 PluginManager::RegisterPlugin(GetPluginNameStatic(), 317 GetPluginDescriptionStatic(), CreateInstance); 318 } 319 320 void UnwindAssemblyInstEmulation::Terminate() { 321 PluginManager::UnregisterPlugin(CreateInstance); 322 } 323 324 ConstString UnwindAssemblyInstEmulation::GetPluginNameStatic() { 325 static ConstString g_name("inst-emulation"); 326 return g_name; 327 } 328 329 const char *UnwindAssemblyInstEmulation::GetPluginDescriptionStatic() { 330 return "Instruction emulation based unwind information."; 331 } 332 333 uint64_t UnwindAssemblyInstEmulation::MakeRegisterKindValuePair( 334 const RegisterInfo ®_info) { 335 lldb::RegisterKind reg_kind; 336 uint32_t reg_num; 337 if (EmulateInstruction::GetBestRegisterKindAndNumber(®_info, reg_kind, 338 reg_num)) 339 return (uint64_t)reg_kind << 24 | reg_num; 340 return 0ull; 341 } 342 343 void UnwindAssemblyInstEmulation::SetRegisterValue( 344 const RegisterInfo ®_info, const RegisterValue ®_value) { 345 m_register_values[MakeRegisterKindValuePair(reg_info)] = reg_value; 346 } 347 348 bool UnwindAssemblyInstEmulation::GetRegisterValue(const RegisterInfo ®_info, 349 RegisterValue ®_value) { 350 const uint64_t reg_id = MakeRegisterKindValuePair(reg_info); 351 RegisterValueMap::const_iterator pos = m_register_values.find(reg_id); 352 if (pos != m_register_values.end()) { 353 reg_value = pos->second; 354 return true; // We had a real value that comes from an opcode that wrote 355 // to it... 356 } 357 // We are making up a value that is recognizable... 358 reg_value.SetUInt(reg_id, reg_info.byte_size); 359 return false; 360 } 361 362 size_t UnwindAssemblyInstEmulation::ReadMemory( 363 EmulateInstruction *instruction, void *baton, 364 const EmulateInstruction::Context &context, lldb::addr_t addr, void *dst, 365 size_t dst_len) { 366 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_UNWIND)); 367 368 if (log && log->GetVerbose()) { 369 StreamString strm; 370 strm.Printf( 371 "UnwindAssemblyInstEmulation::ReadMemory (addr = 0x%16.16" PRIx64 372 ", dst = %p, dst_len = %" PRIu64 ", context = ", 373 addr, dst, (uint64_t)dst_len); 374 context.Dump(strm, instruction); 375 log->PutString(strm.GetString()); 376 } 377 memset(dst, 0, dst_len); 378 return dst_len; 379 } 380 381 size_t UnwindAssemblyInstEmulation::WriteMemory( 382 EmulateInstruction *instruction, void *baton, 383 const EmulateInstruction::Context &context, lldb::addr_t addr, 384 const void *dst, size_t dst_len) { 385 if (baton && dst && dst_len) 386 return ((UnwindAssemblyInstEmulation *)baton) 387 ->WriteMemory(instruction, context, addr, dst, dst_len); 388 return 0; 389 } 390 391 size_t UnwindAssemblyInstEmulation::WriteMemory( 392 EmulateInstruction *instruction, const EmulateInstruction::Context &context, 393 lldb::addr_t addr, const void *dst, size_t dst_len) { 394 DataExtractor data(dst, dst_len, 395 instruction->GetArchitecture().GetByteOrder(), 396 instruction->GetArchitecture().GetAddressByteSize()); 397 398 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_UNWIND)); 399 400 if (log && log->GetVerbose()) { 401 StreamString strm; 402 403 strm.PutCString("UnwindAssemblyInstEmulation::WriteMemory ("); 404 DumpDataExtractor(data, &strm, 0, eFormatBytes, 1, dst_len, UINT32_MAX, 405 addr, 0, 0); 406 strm.PutCString(", context = "); 407 context.Dump(strm, instruction); 408 log->PutString(strm.GetString()); 409 } 410 411 const bool cant_replace = false; 412 413 switch (context.type) { 414 default: 415 case EmulateInstruction::eContextInvalid: 416 case EmulateInstruction::eContextReadOpcode: 417 case EmulateInstruction::eContextImmediate: 418 case EmulateInstruction::eContextAdjustBaseRegister: 419 case EmulateInstruction::eContextRegisterPlusOffset: 420 case EmulateInstruction::eContextAdjustPC: 421 case EmulateInstruction::eContextRegisterStore: 422 case EmulateInstruction::eContextRegisterLoad: 423 case EmulateInstruction::eContextRelativeBranchImmediate: 424 case EmulateInstruction::eContextAbsoluteBranchRegister: 425 case EmulateInstruction::eContextSupervisorCall: 426 case EmulateInstruction::eContextTableBranchReadMemory: 427 case EmulateInstruction::eContextWriteRegisterRandomBits: 428 case EmulateInstruction::eContextWriteMemoryRandomBits: 429 case EmulateInstruction::eContextArithmetic: 430 case EmulateInstruction::eContextAdvancePC: 431 case EmulateInstruction::eContextReturnFromException: 432 case EmulateInstruction::eContextPopRegisterOffStack: 433 case EmulateInstruction::eContextAdjustStackPointer: 434 break; 435 436 case EmulateInstruction::eContextPushRegisterOnStack: { 437 uint32_t reg_num = LLDB_INVALID_REGNUM; 438 uint32_t generic_regnum = LLDB_INVALID_REGNUM; 439 assert(context.info_type == 440 EmulateInstruction::eInfoTypeRegisterToRegisterPlusOffset && 441 "unhandled case, add code to handle this!"); 442 const uint32_t unwind_reg_kind = m_unwind_plan_ptr->GetRegisterKind(); 443 reg_num = context.info.RegisterToRegisterPlusOffset.data_reg 444 .kinds[unwind_reg_kind]; 445 generic_regnum = context.info.RegisterToRegisterPlusOffset.data_reg 446 .kinds[eRegisterKindGeneric]; 447 448 if (reg_num != LLDB_INVALID_REGNUM && 449 generic_regnum != LLDB_REGNUM_GENERIC_SP) { 450 if (m_pushed_regs.find(reg_num) == m_pushed_regs.end()) { 451 m_pushed_regs[reg_num] = addr; 452 const int32_t offset = addr - m_initial_sp; 453 m_curr_row->SetRegisterLocationToAtCFAPlusOffset(reg_num, offset, 454 cant_replace); 455 m_curr_row_modified = true; 456 } 457 } 458 } break; 459 } 460 461 return dst_len; 462 } 463 464 bool UnwindAssemblyInstEmulation::ReadRegister(EmulateInstruction *instruction, 465 void *baton, 466 const RegisterInfo *reg_info, 467 RegisterValue ®_value) { 468 469 if (baton && reg_info) 470 return ((UnwindAssemblyInstEmulation *)baton) 471 ->ReadRegister(instruction, reg_info, reg_value); 472 return false; 473 } 474 bool UnwindAssemblyInstEmulation::ReadRegister(EmulateInstruction *instruction, 475 const RegisterInfo *reg_info, 476 RegisterValue ®_value) { 477 bool synthetic = GetRegisterValue(*reg_info, reg_value); 478 479 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_UNWIND)); 480 481 if (log && log->GetVerbose()) { 482 483 StreamString strm; 484 strm.Printf("UnwindAssemblyInstEmulation::ReadRegister (name = \"%s\") => " 485 "synthetic_value = %i, value = ", 486 reg_info->name, synthetic); 487 DumpRegisterValue(reg_value, &strm, reg_info, false, false, eFormatDefault); 488 log->PutString(strm.GetString()); 489 } 490 return true; 491 } 492 493 bool UnwindAssemblyInstEmulation::WriteRegister( 494 EmulateInstruction *instruction, void *baton, 495 const EmulateInstruction::Context &context, const RegisterInfo *reg_info, 496 const RegisterValue ®_value) { 497 if (baton && reg_info) 498 return ((UnwindAssemblyInstEmulation *)baton) 499 ->WriteRegister(instruction, context, reg_info, reg_value); 500 return false; 501 } 502 bool UnwindAssemblyInstEmulation::WriteRegister( 503 EmulateInstruction *instruction, const EmulateInstruction::Context &context, 504 const RegisterInfo *reg_info, const RegisterValue ®_value) { 505 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_UNWIND)); 506 507 if (log && log->GetVerbose()) { 508 509 StreamString strm; 510 strm.Printf( 511 "UnwindAssemblyInstEmulation::WriteRegister (name = \"%s\", value = ", 512 reg_info->name); 513 DumpRegisterValue(reg_value, &strm, reg_info, false, false, eFormatDefault); 514 strm.PutCString(", context = "); 515 context.Dump(strm, instruction); 516 log->PutString(strm.GetString()); 517 } 518 519 SetRegisterValue(*reg_info, reg_value); 520 521 switch (context.type) { 522 case EmulateInstruction::eContextInvalid: 523 case EmulateInstruction::eContextReadOpcode: 524 case EmulateInstruction::eContextImmediate: 525 case EmulateInstruction::eContextAdjustBaseRegister: 526 case EmulateInstruction::eContextRegisterPlusOffset: 527 case EmulateInstruction::eContextAdjustPC: 528 case EmulateInstruction::eContextRegisterStore: 529 case EmulateInstruction::eContextSupervisorCall: 530 case EmulateInstruction::eContextTableBranchReadMemory: 531 case EmulateInstruction::eContextWriteRegisterRandomBits: 532 case EmulateInstruction::eContextWriteMemoryRandomBits: 533 case EmulateInstruction::eContextAdvancePC: 534 case EmulateInstruction::eContextReturnFromException: 535 case EmulateInstruction::eContextPushRegisterOnStack: 536 case EmulateInstruction::eContextRegisterLoad: 537 // { 538 // const uint32_t reg_num = 539 // reg_info->kinds[m_unwind_plan_ptr->GetRegisterKind()]; 540 // if (reg_num != LLDB_INVALID_REGNUM) 541 // { 542 // const bool can_replace_only_if_unspecified = true; 543 // 544 // m_curr_row.SetRegisterLocationToUndefined (reg_num, 545 // can_replace_only_if_unspecified, 546 // can_replace_only_if_unspecified); 547 // m_curr_row_modified = true; 548 // } 549 // } 550 break; 551 552 case EmulateInstruction::eContextArithmetic: { 553 // If we adjusted the current frame pointer by a constant then adjust the 554 // CFA offset 555 // with the same amount. 556 lldb::RegisterKind kind = m_unwind_plan_ptr->GetRegisterKind(); 557 if (m_fp_is_cfa && reg_info->kinds[kind] == m_cfa_reg_info.kinds[kind] && 558 context.info_type == EmulateInstruction::eInfoTypeRegisterPlusOffset && 559 context.info.RegisterPlusOffset.reg.kinds[kind] == 560 m_cfa_reg_info.kinds[kind]) { 561 const int64_t offset = context.info.RegisterPlusOffset.signed_offset; 562 m_curr_row->GetCFAValue().IncOffset(-1 * offset); 563 m_curr_row_modified = true; 564 } 565 } break; 566 567 case EmulateInstruction::eContextAbsoluteBranchRegister: 568 case EmulateInstruction::eContextRelativeBranchImmediate: { 569 if (context.info_type == EmulateInstruction::eInfoTypeISAAndImmediate && 570 context.info.ISAAndImmediate.unsigned_data32 > 0) { 571 m_forward_branch_offset = 572 context.info.ISAAndImmediateSigned.signed_data32; 573 } else if (context.info_type == 574 EmulateInstruction::eInfoTypeISAAndImmediateSigned && 575 context.info.ISAAndImmediateSigned.signed_data32 > 0) { 576 m_forward_branch_offset = context.info.ISAAndImmediate.unsigned_data32; 577 } else if (context.info_type == EmulateInstruction::eInfoTypeImmediate && 578 context.info.unsigned_immediate > 0) { 579 m_forward_branch_offset = context.info.unsigned_immediate; 580 } else if (context.info_type == 581 EmulateInstruction::eInfoTypeImmediateSigned && 582 context.info.signed_immediate > 0) { 583 m_forward_branch_offset = context.info.signed_immediate; 584 } 585 } break; 586 587 case EmulateInstruction::eContextPopRegisterOffStack: { 588 const uint32_t reg_num = 589 reg_info->kinds[m_unwind_plan_ptr->GetRegisterKind()]; 590 const uint32_t generic_regnum = reg_info->kinds[eRegisterKindGeneric]; 591 if (reg_num != LLDB_INVALID_REGNUM && 592 generic_regnum != LLDB_REGNUM_GENERIC_SP) { 593 switch (context.info_type) { 594 case EmulateInstruction::eInfoTypeAddress: 595 if (m_pushed_regs.find(reg_num) != m_pushed_regs.end() && 596 context.info.address == m_pushed_regs[reg_num]) { 597 m_curr_row->SetRegisterLocationToSame(reg_num, 598 false /*must_replace*/); 599 m_curr_row_modified = true; 600 } 601 break; 602 case EmulateInstruction::eInfoTypeISA: 603 assert( 604 (generic_regnum == LLDB_REGNUM_GENERIC_PC || 605 generic_regnum == LLDB_REGNUM_GENERIC_FLAGS) && 606 "eInfoTypeISA used for popping a register other the PC/FLAGS"); 607 if (generic_regnum != LLDB_REGNUM_GENERIC_FLAGS) { 608 m_curr_row->SetRegisterLocationToSame(reg_num, 609 false /*must_replace*/); 610 m_curr_row_modified = true; 611 } 612 break; 613 default: 614 assert(false && "unhandled case, add code to handle this!"); 615 break; 616 } 617 } 618 } break; 619 620 case EmulateInstruction::eContextSetFramePointer: 621 if (!m_fp_is_cfa) { 622 m_fp_is_cfa = true; 623 m_cfa_reg_info = *reg_info; 624 const uint32_t cfa_reg_num = 625 reg_info->kinds[m_unwind_plan_ptr->GetRegisterKind()]; 626 assert(cfa_reg_num != LLDB_INVALID_REGNUM); 627 m_curr_row->GetCFAValue().SetIsRegisterPlusOffset( 628 cfa_reg_num, m_initial_sp - reg_value.GetAsUInt64()); 629 m_curr_row_modified = true; 630 } 631 break; 632 633 case EmulateInstruction::eContextRestoreStackPointer: 634 if (m_fp_is_cfa) { 635 m_fp_is_cfa = false; 636 m_cfa_reg_info = *reg_info; 637 const uint32_t cfa_reg_num = 638 reg_info->kinds[m_unwind_plan_ptr->GetRegisterKind()]; 639 assert(cfa_reg_num != LLDB_INVALID_REGNUM); 640 m_curr_row->GetCFAValue().SetIsRegisterPlusOffset( 641 cfa_reg_num, m_initial_sp - reg_value.GetAsUInt64()); 642 m_curr_row_modified = true; 643 } 644 break; 645 646 case EmulateInstruction::eContextAdjustStackPointer: 647 // If we have created a frame using the frame pointer, don't follow 648 // subsequent adjustments to the stack pointer. 649 if (!m_fp_is_cfa) { 650 m_curr_row->GetCFAValue().SetIsRegisterPlusOffset( 651 m_curr_row->GetCFAValue().GetRegisterNumber(), 652 m_initial_sp - reg_value.GetAsUInt64()); 653 m_curr_row_modified = true; 654 } 655 break; 656 } 657 return true; 658 } 659