1 //===-- UnwindAssemblyInstEmulation.cpp --------------------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #include "UnwindAssemblyInstEmulation.h" 11 12 #include "llvm-c/EnhancedDisassembly.h" 13 14 #include "lldb/Core/Address.h" 15 #include "lldb/Core/ArchSpec.h" 16 #include "lldb/Core/DataBufferHeap.h" 17 #include "lldb/Core/Disassembler.h" 18 #include "lldb/Core/Error.h" 19 #include "lldb/Core/Log.h" 20 #include "lldb/Core/PluginManager.h" 21 #include "lldb/Core/StreamString.h" 22 #include "lldb/Target/ExecutionContext.h" 23 #include "lldb/Target/Process.h" 24 #include "lldb/Target/Thread.h" 25 #include "lldb/Target/Target.h" 26 27 using namespace lldb; 28 using namespace lldb_private; 29 30 31 32 //----------------------------------------------------------------------------------------------- 33 // UnwindAssemblyParser_x86 method definitions 34 //----------------------------------------------------------------------------------------------- 35 36 bool 37 UnwindAssemblyInstEmulation::GetNonCallSiteUnwindPlanFromAssembly (AddressRange& range, 38 Thread& thread, 39 UnwindPlan& unwind_plan) 40 { 41 if (range.GetByteSize() > 0 && 42 range.GetBaseAddress().IsValid() && 43 m_inst_emulator_ap.get()) 44 { 45 46 // The the instruction emulation subclass setup the unwind plan for the 47 // first instruction. 48 m_inst_emulator_ap->CreateFunctionEntryUnwind (unwind_plan); 49 50 // CreateFunctionEntryUnwind should have created the first row. If it 51 // doesn't, then we are done. 52 if (unwind_plan.GetRowCount() == 0) 53 return false; 54 55 ExecutionContext exe_ctx; 56 thread.CalculateExecutionContext(exe_ctx); 57 DisassemblerSP disasm_sp (Disassembler::DisassembleRange (m_arch, 58 NULL, 59 exe_ctx, 60 range)); 61 62 LogSP log(GetLogIfAllCategoriesSet (LIBLLDB_LOG_UNWIND)); 63 64 if (disasm_sp) 65 { 66 67 m_range_ptr = ⦥ 68 m_thread_ptr = &thread; 69 m_unwind_plan_ptr = &unwind_plan; 70 71 const uint32_t addr_byte_size = m_arch.GetAddressByteSize(); 72 const bool show_address = true; 73 const bool show_bytes = true; 74 const bool raw = false; 75 // Initialize the CFA with a known value. In the 32 bit case 76 // it will be 0x80000000, and in the 64 bit case 0x8000000000000000. 77 // We use the address byte size to be safe for any future addresss sizes 78 m_inst_emulator_ap->GetRegisterInfo (unwind_plan.GetRegisterKind(), 79 unwind_plan.GetInitialCFARegister(), 80 m_cfa_reg_info); 81 82 m_fp_is_cfa = false; 83 m_register_values.clear(); 84 m_pushed_regs.clear(); 85 86 m_initial_sp = (1ull << ((addr_byte_size * 8) - 1)); 87 RegisterValue cfa_reg_value; 88 cfa_reg_value.SetUInt (m_initial_sp, m_cfa_reg_info.byte_size); 89 SetRegisterValue (m_cfa_reg_info, cfa_reg_value); 90 91 const InstructionList &inst_list = disasm_sp->GetInstructionList (); 92 const size_t num_instructions = inst_list.GetSize(); 93 if (num_instructions > 0) 94 { 95 Instruction *inst = inst_list.GetInstructionAtIndex (0).get(); 96 const addr_t base_addr = inst->GetAddress().GetFileAddress(); 97 // Initialize the current row with the one row that was created 98 // from the CreateFunctionEntryUnwind call above... 99 m_curr_row = unwind_plan.GetLastRow(); 100 101 for (size_t idx=0; idx<num_instructions; ++idx) 102 { 103 inst = inst_list.GetInstructionAtIndex (idx).get(); 104 if (inst) 105 { 106 107 if (log && log->GetVerbose ()) 108 { 109 StreamString strm; 110 inst->Dump(&strm, inst_list.GetMaxOpcocdeByteSize (), show_address, show_bytes, &exe_ctx, raw); 111 log->PutCString (strm.GetData()); 112 } 113 114 m_inst_emulator_ap->SetInstruction (inst->GetOpcode(), 115 inst->GetAddress(), 116 exe_ctx.GetTargetPtr()); 117 118 m_inst_emulator_ap->EvaluateInstruction (eEmulateInstructionOptionIgnoreConditions); 119 120 if (unwind_plan.GetLastRow() != m_curr_row) 121 { 122 // Be sure to not edit the offset unless our row has changed 123 // so that the "!=" call above doesn't trigger every time 124 m_curr_row.SetOffset (inst->GetAddress().GetFileAddress() + inst->GetOpcode().GetByteSize() - base_addr); 125 // Append the new row 126 unwind_plan.AppendRow (m_curr_row); 127 } 128 } 129 } 130 } 131 } 132 133 if (log && log->GetVerbose ()) 134 { 135 StreamString strm; 136 lldb::addr_t base_addr = range.GetBaseAddress().GetLoadAddress(&thread.GetProcess().GetTarget()); 137 strm.Printf ("Resulting unwind rows for [0x%llx - 0x%llx):", base_addr, base_addr + range.GetByteSize()); 138 unwind_plan.Dump(strm, &thread, base_addr); 139 log->PutCString (strm.GetData()); 140 } 141 return unwind_plan.GetRowCount() > 0; 142 } 143 return false; 144 } 145 146 bool 147 UnwindAssemblyInstEmulation::GetFastUnwindPlan (AddressRange& func, 148 Thread& thread, 149 UnwindPlan &unwind_plan) 150 { 151 return false; 152 } 153 154 bool 155 UnwindAssemblyInstEmulation::FirstNonPrologueInsn (AddressRange& func, 156 Target& target, 157 Thread* thread, 158 Address& first_non_prologue_insn) 159 { 160 return false; 161 } 162 163 UnwindAssembly * 164 UnwindAssemblyInstEmulation::CreateInstance (const ArchSpec &arch) 165 { 166 std::auto_ptr<EmulateInstruction> inst_emulator_ap (EmulateInstruction::FindPlugin (arch, eInstructionTypePrologueEpilogue, NULL)); 167 // Make sure that all prologue instructions are handled 168 if (inst_emulator_ap.get()) 169 return new UnwindAssemblyInstEmulation (arch, inst_emulator_ap.release()); 170 return NULL; 171 } 172 173 174 //------------------------------------------------------------------ 175 // PluginInterface protocol in UnwindAssemblyParser_x86 176 //------------------------------------------------------------------ 177 178 const char * 179 UnwindAssemblyInstEmulation::GetPluginName() 180 { 181 return "UnwindAssemblyInstEmulation"; 182 } 183 184 const char * 185 UnwindAssemblyInstEmulation::GetShortPluginName() 186 { 187 return "unwindassembly.inst-emulation"; 188 } 189 190 191 uint32_t 192 UnwindAssemblyInstEmulation::GetPluginVersion() 193 { 194 return 1; 195 } 196 197 void 198 UnwindAssemblyInstEmulation::Initialize() 199 { 200 PluginManager::RegisterPlugin (GetPluginNameStatic(), 201 GetPluginDescriptionStatic(), 202 CreateInstance); 203 } 204 205 void 206 UnwindAssemblyInstEmulation::Terminate() 207 { 208 PluginManager::UnregisterPlugin (CreateInstance); 209 } 210 211 212 const char * 213 UnwindAssemblyInstEmulation::GetPluginNameStatic() 214 { 215 return "UnwindAssemblyInstEmulation"; 216 } 217 218 const char * 219 UnwindAssemblyInstEmulation::GetPluginDescriptionStatic() 220 { 221 return "Instruction emulation based unwind information."; 222 } 223 224 225 uint64_t 226 UnwindAssemblyInstEmulation::MakeRegisterKindValuePair (const RegisterInfo ®_info) 227 { 228 uint32_t reg_kind, reg_num; 229 if (EmulateInstruction::GetBestRegisterKindAndNumber (®_info, reg_kind, reg_num)) 230 return (uint64_t)reg_kind << 24 | reg_num; 231 return 0ull; 232 } 233 234 void 235 UnwindAssemblyInstEmulation::SetRegisterValue (const RegisterInfo ®_info, const RegisterValue ®_value) 236 { 237 m_register_values[MakeRegisterKindValuePair (reg_info)] = reg_value; 238 } 239 240 bool 241 UnwindAssemblyInstEmulation::GetRegisterValue (const RegisterInfo ®_info, RegisterValue ®_value) 242 { 243 const uint64_t reg_id = MakeRegisterKindValuePair (reg_info); 244 RegisterValueMap::const_iterator pos = m_register_values.find(reg_id); 245 if (pos != m_register_values.end()) 246 { 247 reg_value = pos->second; 248 return true; // We had a real value that comes from an opcode that wrote 249 // to it... 250 } 251 // We are making up a value that is recognizable... 252 reg_value.SetUInt(reg_id, reg_info.byte_size); 253 return false; 254 } 255 256 257 size_t 258 UnwindAssemblyInstEmulation::ReadMemory (EmulateInstruction *instruction, 259 void *baton, 260 const EmulateInstruction::Context &context, 261 lldb::addr_t addr, 262 void *dst, 263 size_t dst_len) 264 { 265 LogSP log(GetLogIfAllCategoriesSet (LIBLLDB_LOG_UNWIND)); 266 267 if (log && log->GetVerbose ()) 268 { 269 StreamString strm; 270 strm.Printf ("UnwindAssemblyInstEmulation::ReadMemory (addr = 0x%16.16llx, dst = %p, dst_len = %zu, context = ", 271 addr, 272 dst, 273 dst_len); 274 context.Dump(strm, instruction); 275 log->PutCString (strm.GetData ()); 276 } 277 return dst_len; 278 } 279 280 size_t 281 UnwindAssemblyInstEmulation::WriteMemory (EmulateInstruction *instruction, 282 void *baton, 283 const EmulateInstruction::Context &context, 284 lldb::addr_t addr, 285 const void *dst, 286 size_t dst_len) 287 { 288 if (baton && dst && dst_len) 289 return ((UnwindAssemblyInstEmulation *)baton)->WriteMemory (instruction, context, addr, dst, dst_len); 290 return 0; 291 } 292 293 size_t 294 UnwindAssemblyInstEmulation::WriteMemory (EmulateInstruction *instruction, 295 const EmulateInstruction::Context &context, 296 lldb::addr_t addr, 297 const void *dst, 298 size_t dst_len) 299 { 300 DataExtractor data (dst, 301 dst_len, 302 instruction->GetArchitecture ().GetByteOrder(), 303 instruction->GetArchitecture ().GetAddressByteSize()); 304 305 LogSP log(GetLogIfAllCategoriesSet (LIBLLDB_LOG_UNWIND)); 306 307 if (log && log->GetVerbose ()) 308 { 309 StreamString strm; 310 311 strm.PutCString ("UnwindAssemblyInstEmulation::WriteMemory ("); 312 data.Dump(&strm, 0, eFormatBytes, 1, dst_len, UINT32_MAX, addr, 0, 0); 313 strm.PutCString (", context = "); 314 context.Dump(strm, instruction); 315 log->PutCString (strm.GetData()); 316 } 317 318 const bool can_replace = true; 319 const bool cant_replace = false; 320 321 switch (context.type) 322 { 323 default: 324 case EmulateInstruction::eContextInvalid: 325 case EmulateInstruction::eContextReadOpcode: 326 case EmulateInstruction::eContextImmediate: 327 case EmulateInstruction::eContextAdjustBaseRegister: 328 case EmulateInstruction::eContextRegisterPlusOffset: 329 case EmulateInstruction::eContextAdjustPC: 330 case EmulateInstruction::eContextRegisterStore: 331 case EmulateInstruction::eContextRegisterLoad: 332 case EmulateInstruction::eContextRelativeBranchImmediate: 333 case EmulateInstruction::eContextAbsoluteBranchRegister: 334 case EmulateInstruction::eContextSupervisorCall: 335 case EmulateInstruction::eContextTableBranchReadMemory: 336 case EmulateInstruction::eContextWriteRegisterRandomBits: 337 case EmulateInstruction::eContextWriteMemoryRandomBits: 338 case EmulateInstruction::eContextArithmetic: 339 case EmulateInstruction::eContextAdvancePC: 340 case EmulateInstruction::eContextReturnFromException: 341 case EmulateInstruction::eContextPopRegisterOffStack: 342 case EmulateInstruction::eContextAdjustStackPointer: 343 break; 344 345 case EmulateInstruction::eContextPushRegisterOnStack: 346 { 347 uint32_t reg_num = LLDB_INVALID_REGNUM; 348 bool is_return_address_reg = false; 349 const uint32_t unwind_reg_kind = m_unwind_plan_ptr->GetRegisterKind(); 350 if (context.info_type == EmulateInstruction::eInfoTypeRegisterToRegisterPlusOffset) 351 { 352 reg_num = context.info.RegisterToRegisterPlusOffset.data_reg.kinds[unwind_reg_kind]; 353 if (context.info.RegisterToRegisterPlusOffset.data_reg.kinds[eRegisterKindGeneric] == LLDB_REGNUM_GENERIC_RA) 354 is_return_address_reg = true; 355 } 356 else 357 { 358 assert (!"unhandled case, add code to handle this!"); 359 } 360 361 if (reg_num != LLDB_INVALID_REGNUM) 362 { 363 if (m_pushed_regs.find (reg_num) == m_pushed_regs.end()) 364 { 365 m_pushed_regs[reg_num] = addr; 366 const int32_t offset = addr - m_initial_sp; 367 m_curr_row.SetRegisterLocationToAtCFAPlusOffset (reg_num, offset, cant_replace); 368 if (is_return_address_reg) 369 { 370 // This push was pushing the return address register, 371 // so this is also how we will unwind the PC... 372 RegisterInfo pc_reg_info; 373 if (instruction->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC, pc_reg_info)) 374 { 375 uint32_t pc_reg_num = pc_reg_info.kinds[unwind_reg_kind]; 376 if (pc_reg_num != LLDB_INVALID_REGNUM) 377 m_curr_row.SetRegisterLocationToAtCFAPlusOffset (pc_reg_num, offset, can_replace); 378 } 379 } 380 } 381 } 382 } 383 break; 384 385 } 386 387 return dst_len; 388 } 389 390 bool 391 UnwindAssemblyInstEmulation::ReadRegister (EmulateInstruction *instruction, 392 void *baton, 393 const RegisterInfo *reg_info, 394 RegisterValue ®_value) 395 { 396 397 if (baton && reg_info) 398 return ((UnwindAssemblyInstEmulation *)baton)->ReadRegister (instruction, reg_info, reg_value); 399 return false; 400 } 401 bool 402 UnwindAssemblyInstEmulation::ReadRegister (EmulateInstruction *instruction, 403 const RegisterInfo *reg_info, 404 RegisterValue ®_value) 405 { 406 bool synthetic = GetRegisterValue (*reg_info, reg_value); 407 408 LogSP log(GetLogIfAllCategoriesSet (LIBLLDB_LOG_UNWIND)); 409 410 if (log && log->GetVerbose ()) 411 { 412 413 StreamString strm; 414 strm.Printf ("UnwindAssemblyInstEmulation::ReadRegister (name = \"%s\") => synthetic_value = %i, value = ", reg_info->name, synthetic); 415 reg_value.Dump(&strm, reg_info, false, false, eFormatDefault); 416 log->PutCString(strm.GetData()); 417 } 418 return true; 419 } 420 421 bool 422 UnwindAssemblyInstEmulation::WriteRegister (EmulateInstruction *instruction, 423 void *baton, 424 const EmulateInstruction::Context &context, 425 const RegisterInfo *reg_info, 426 const RegisterValue ®_value) 427 { 428 if (baton && reg_info) 429 return ((UnwindAssemblyInstEmulation *)baton)->WriteRegister (instruction, context, reg_info, reg_value); 430 return false; 431 } 432 bool 433 UnwindAssemblyInstEmulation::WriteRegister (EmulateInstruction *instruction, 434 const EmulateInstruction::Context &context, 435 const RegisterInfo *reg_info, 436 const RegisterValue ®_value) 437 { 438 LogSP log(GetLogIfAllCategoriesSet (LIBLLDB_LOG_UNWIND)); 439 440 if (log && log->GetVerbose ()) 441 { 442 443 StreamString strm; 444 strm.Printf ("UnwindAssemblyInstEmulation::WriteRegister (name = \"%s\", value = ", reg_info->name); 445 reg_value.Dump(&strm, reg_info, false, false, eFormatDefault); 446 strm.PutCString (", context = "); 447 context.Dump(strm, instruction); 448 log->PutCString(strm.GetData()); 449 } 450 451 const bool must_replace = true; 452 SetRegisterValue (*reg_info, reg_value); 453 454 switch (context.type) 455 { 456 default: 457 case EmulateInstruction::eContextInvalid: 458 case EmulateInstruction::eContextReadOpcode: 459 case EmulateInstruction::eContextImmediate: 460 case EmulateInstruction::eContextAdjustBaseRegister: 461 case EmulateInstruction::eContextRegisterPlusOffset: 462 case EmulateInstruction::eContextAdjustPC: 463 case EmulateInstruction::eContextRegisterStore: 464 case EmulateInstruction::eContextRegisterLoad: 465 case EmulateInstruction::eContextRelativeBranchImmediate: 466 case EmulateInstruction::eContextAbsoluteBranchRegister: 467 case EmulateInstruction::eContextSupervisorCall: 468 case EmulateInstruction::eContextTableBranchReadMemory: 469 case EmulateInstruction::eContextWriteRegisterRandomBits: 470 case EmulateInstruction::eContextWriteMemoryRandomBits: 471 case EmulateInstruction::eContextArithmetic: 472 case EmulateInstruction::eContextAdvancePC: 473 case EmulateInstruction::eContextReturnFromException: 474 case EmulateInstruction::eContextPushRegisterOnStack: 475 // { 476 // const uint32_t reg_num = reg_info->kinds[m_unwind_plan_ptr->GetRegisterKind()]; 477 // if (reg_num != LLDB_INVALID_REGNUM) 478 // { 479 // const bool can_replace_only_if_unspecified = true; 480 // 481 // m_curr_row.SetRegisterLocationToUndefined (reg_num, 482 // can_replace_only_if_unspecified, 483 // can_replace_only_if_unspecified); 484 // } 485 // } 486 break; 487 488 case EmulateInstruction::eContextPopRegisterOffStack: 489 { 490 const uint32_t reg_num = reg_info->kinds[m_unwind_plan_ptr->GetRegisterKind()]; 491 if (reg_num != LLDB_INVALID_REGNUM) 492 { 493 m_curr_row.SetRegisterLocationToSame (reg_num, must_replace); 494 } 495 } 496 break; 497 498 case EmulateInstruction::eContextSetFramePointer: 499 if (!m_fp_is_cfa) 500 { 501 m_fp_is_cfa = true; 502 m_cfa_reg_info = *reg_info; 503 const uint32_t cfa_reg_num = reg_info->kinds[m_unwind_plan_ptr->GetRegisterKind()]; 504 assert (cfa_reg_num != LLDB_INVALID_REGNUM); 505 m_curr_row.SetCFARegister(cfa_reg_num); 506 m_curr_row.SetCFAOffset(m_initial_sp - reg_value.GetAsUInt64()); 507 } 508 break; 509 510 case EmulateInstruction::eContextAdjustStackPointer: 511 // If we have created a frame using the frame pointer, don't follow 512 // subsequent adjustments to the stack pointer. 513 if (!m_fp_is_cfa) 514 { 515 m_curr_row.SetCFAOffset (m_initial_sp - reg_value.GetAsUInt64()); 516 } 517 break; 518 } 519 return true; 520 } 521 522 523