1 //===-- ABISysV_arm64.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 "ABISysV_arm64.h" 10 11 #include <optional> 12 #include <vector> 13 14 #include "llvm/ADT/STLExtras.h" 15 #include "llvm/ADT/Triple.h" 16 17 #include "lldb/Core/Module.h" 18 #include "lldb/Core/PluginManager.h" 19 #include "lldb/Core/Value.h" 20 #include "lldb/Core/ValueObjectConstResult.h" 21 #include "lldb/Symbol/UnwindPlan.h" 22 #include "lldb/Target/Process.h" 23 #include "lldb/Target/RegisterContext.h" 24 #include "lldb/Target/Target.h" 25 #include "lldb/Target/Thread.h" 26 #include "lldb/Utility/ConstString.h" 27 #include "lldb/Utility/LLDBLog.h" 28 #include "lldb/Utility/Log.h" 29 #include "lldb/Utility/RegisterValue.h" 30 #include "lldb/Utility/Scalar.h" 31 #include "lldb/Utility/Status.h" 32 33 #include "Utility/ARM64_DWARF_Registers.h" 34 35 using namespace lldb; 36 using namespace lldb_private; 37 38 bool ABISysV_arm64::GetPointerReturnRegister(const char *&name) { 39 name = "x0"; 40 return true; 41 } 42 43 size_t ABISysV_arm64::GetRedZoneSize() const { return 128; } 44 45 // Static Functions 46 47 ABISP 48 ABISysV_arm64::CreateInstance(lldb::ProcessSP process_sp, const ArchSpec &arch) { 49 const llvm::Triple::ArchType arch_type = arch.GetTriple().getArch(); 50 const llvm::Triple::VendorType vendor_type = arch.GetTriple().getVendor(); 51 52 if (vendor_type != llvm::Triple::Apple) { 53 if (arch_type == llvm::Triple::aarch64 || 54 arch_type == llvm::Triple::aarch64_32) { 55 return ABISP( 56 new ABISysV_arm64(std::move(process_sp), MakeMCRegisterInfo(arch))); 57 } 58 } 59 60 return ABISP(); 61 } 62 63 bool ABISysV_arm64::PrepareTrivialCall(Thread &thread, addr_t sp, 64 addr_t func_addr, addr_t return_addr, 65 llvm::ArrayRef<addr_t> args) const { 66 RegisterContext *reg_ctx = thread.GetRegisterContext().get(); 67 if (!reg_ctx) 68 return false; 69 70 Log *log = GetLog(LLDBLog::Expressions); 71 72 if (log) { 73 StreamString s; 74 s.Printf("ABISysV_arm64::PrepareTrivialCall (tid = 0x%" PRIx64 75 ", sp = 0x%" PRIx64 ", func_addr = 0x%" PRIx64 76 ", return_addr = 0x%" PRIx64, 77 thread.GetID(), (uint64_t)sp, (uint64_t)func_addr, 78 (uint64_t)return_addr); 79 80 for (size_t i = 0; i < args.size(); ++i) 81 s.Printf(", arg%d = 0x%" PRIx64, static_cast<int>(i + 1), args[i]); 82 s.PutCString(")"); 83 log->PutString(s.GetString()); 84 } 85 86 // x0 - x7 contain first 8 simple args 87 if (args.size() > 8) 88 return false; 89 90 for (size_t i = 0; i < args.size(); ++i) { 91 const RegisterInfo *reg_info = reg_ctx->GetRegisterInfo( 92 eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1 + i); 93 LLDB_LOGF(log, "About to write arg%d (0x%" PRIx64 ") into %s", 94 static_cast<int>(i + 1), args[i], reg_info->name); 95 if (!reg_ctx->WriteRegisterFromUnsigned(reg_info, args[i])) 96 return false; 97 } 98 99 // Set "lr" to the return address 100 if (!reg_ctx->WriteRegisterFromUnsigned( 101 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, 102 LLDB_REGNUM_GENERIC_RA), 103 return_addr)) 104 return false; 105 106 // Set "sp" to the requested value 107 if (!reg_ctx->WriteRegisterFromUnsigned( 108 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, 109 LLDB_REGNUM_GENERIC_SP), 110 sp)) 111 return false; 112 113 // Set "pc" to the address requested 114 if (!reg_ctx->WriteRegisterFromUnsigned( 115 reg_ctx->GetRegisterInfo(eRegisterKindGeneric, 116 LLDB_REGNUM_GENERIC_PC), 117 func_addr)) 118 return false; 119 120 return true; 121 } 122 123 // TODO: We dont support fp/SIMD arguments in v0-v7 124 bool ABISysV_arm64::GetArgumentValues(Thread &thread, ValueList &values) const { 125 uint32_t num_values = values.GetSize(); 126 127 ExecutionContext exe_ctx(thread.shared_from_this()); 128 129 // Extract the register context so we can read arguments from registers 130 131 RegisterContext *reg_ctx = thread.GetRegisterContext().get(); 132 133 if (!reg_ctx) 134 return false; 135 136 addr_t sp = 0; 137 138 for (uint32_t value_idx = 0; value_idx < num_values; ++value_idx) { 139 // We currently only support extracting values with Clang QualTypes. Do we 140 // care about others? 141 Value *value = values.GetValueAtIndex(value_idx); 142 143 if (!value) 144 return false; 145 146 CompilerType value_type = value->GetCompilerType(); 147 if (value_type) { 148 bool is_signed = false; 149 size_t bit_width = 0; 150 std::optional<uint64_t> bit_size = value_type.GetBitSize(&thread); 151 if (!bit_size) 152 return false; 153 if (value_type.IsIntegerOrEnumerationType(is_signed)) { 154 bit_width = *bit_size; 155 } else if (value_type.IsPointerOrReferenceType()) { 156 bit_width = *bit_size; 157 } else { 158 // We only handle integer, pointer and reference types currently... 159 return false; 160 } 161 162 if (bit_width <= (exe_ctx.GetProcessRef().GetAddressByteSize() * 8)) { 163 if (value_idx < 8) { 164 // Arguments 1-8 are in x0-x7... 165 const RegisterInfo *reg_info = nullptr; 166 reg_info = reg_ctx->GetRegisterInfo( 167 eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1 + value_idx); 168 169 if (reg_info) { 170 RegisterValue reg_value; 171 172 if (reg_ctx->ReadRegister(reg_info, reg_value)) { 173 if (is_signed) 174 reg_value.SignExtend(bit_width); 175 if (!reg_value.GetScalarValue(value->GetScalar())) 176 return false; 177 continue; 178 } 179 } 180 return false; 181 } else { 182 // TODO: Verify for stack layout for SysV 183 if (sp == 0) { 184 // Read the stack pointer if we already haven't read it 185 sp = reg_ctx->GetSP(0); 186 if (sp == 0) 187 return false; 188 } 189 190 // Arguments 5 on up are on the stack 191 const uint32_t arg_byte_size = (bit_width + (8 - 1)) / 8; 192 Status error; 193 if (!exe_ctx.GetProcessRef().ReadScalarIntegerFromMemory( 194 sp, arg_byte_size, is_signed, value->GetScalar(), error)) 195 return false; 196 197 sp += arg_byte_size; 198 // Align up to the next 8 byte boundary if needed 199 if (sp % 8) { 200 sp >>= 3; 201 sp += 1; 202 sp <<= 3; 203 } 204 } 205 } 206 } 207 } 208 return true; 209 } 210 211 Status ABISysV_arm64::SetReturnValueObject(lldb::StackFrameSP &frame_sp, 212 lldb::ValueObjectSP &new_value_sp) { 213 Status error; 214 if (!new_value_sp) { 215 error.SetErrorString("Empty value object for return value."); 216 return error; 217 } 218 219 CompilerType return_value_type = new_value_sp->GetCompilerType(); 220 if (!return_value_type) { 221 error.SetErrorString("Null clang type for return value."); 222 return error; 223 } 224 225 Thread *thread = frame_sp->GetThread().get(); 226 227 RegisterContext *reg_ctx = thread->GetRegisterContext().get(); 228 229 if (reg_ctx) { 230 DataExtractor data; 231 Status data_error; 232 const uint64_t byte_size = new_value_sp->GetData(data, data_error); 233 if (data_error.Fail()) { 234 error.SetErrorStringWithFormat( 235 "Couldn't convert return value to raw data: %s", 236 data_error.AsCString()); 237 return error; 238 } 239 240 const uint32_t type_flags = return_value_type.GetTypeInfo(nullptr); 241 if (type_flags & eTypeIsScalar || type_flags & eTypeIsPointer) { 242 if (type_flags & eTypeIsInteger || type_flags & eTypeIsPointer) { 243 // Extract the register context so we can read arguments from registers 244 lldb::offset_t offset = 0; 245 if (byte_size <= 16) { 246 const RegisterInfo *x0_info = reg_ctx->GetRegisterInfo( 247 eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1); 248 if (byte_size <= 8) { 249 uint64_t raw_value = data.GetMaxU64(&offset, byte_size); 250 251 if (!reg_ctx->WriteRegisterFromUnsigned(x0_info, raw_value)) 252 error.SetErrorString("failed to write register x0"); 253 } else { 254 uint64_t raw_value = data.GetMaxU64(&offset, 8); 255 256 if (reg_ctx->WriteRegisterFromUnsigned(x0_info, raw_value)) { 257 const RegisterInfo *x1_info = reg_ctx->GetRegisterInfo( 258 eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG2); 259 raw_value = data.GetMaxU64(&offset, byte_size - offset); 260 261 if (!reg_ctx->WriteRegisterFromUnsigned(x1_info, raw_value)) 262 error.SetErrorString("failed to write register x1"); 263 } 264 } 265 } else { 266 error.SetErrorString("We don't support returning longer than 128 bit " 267 "integer values at present."); 268 } 269 } else if (type_flags & eTypeIsFloat) { 270 if (type_flags & eTypeIsComplex) { 271 // Don't handle complex yet. 272 error.SetErrorString( 273 "returning complex float values are not supported"); 274 } else { 275 const RegisterInfo *v0_info = reg_ctx->GetRegisterInfoByName("v0", 0); 276 277 if (v0_info) { 278 if (byte_size <= 16) { 279 if (byte_size <= RegisterValue::GetMaxByteSize()) { 280 RegisterValue reg_value; 281 error = reg_value.SetValueFromData(*v0_info, data, 0, true); 282 if (error.Success()) { 283 if (!reg_ctx->WriteRegister(v0_info, reg_value)) 284 error.SetErrorString("failed to write register v0"); 285 } 286 } else { 287 error.SetErrorStringWithFormat( 288 "returning float values with a byte size of %" PRIu64 289 " are not supported", 290 byte_size); 291 } 292 } else { 293 error.SetErrorString("returning float values longer than 128 " 294 "bits are not supported"); 295 } 296 } else { 297 error.SetErrorString("v0 register is not available on this target"); 298 } 299 } 300 } 301 } else if (type_flags & eTypeIsVector) { 302 if (byte_size > 0) { 303 const RegisterInfo *v0_info = reg_ctx->GetRegisterInfoByName("v0", 0); 304 305 if (v0_info) { 306 if (byte_size <= v0_info->byte_size) { 307 RegisterValue reg_value; 308 error = reg_value.SetValueFromData(*v0_info, data, 0, true); 309 if (error.Success()) { 310 if (!reg_ctx->WriteRegister(v0_info, reg_value)) 311 error.SetErrorString("failed to write register v0"); 312 } 313 } 314 } 315 } 316 } 317 } else { 318 error.SetErrorString("no registers are available"); 319 } 320 321 return error; 322 } 323 324 bool ABISysV_arm64::CreateFunctionEntryUnwindPlan(UnwindPlan &unwind_plan) { 325 unwind_plan.Clear(); 326 unwind_plan.SetRegisterKind(eRegisterKindDWARF); 327 328 uint32_t lr_reg_num = arm64_dwarf::lr; 329 uint32_t sp_reg_num = arm64_dwarf::sp; 330 331 UnwindPlan::RowSP row(new UnwindPlan::Row); 332 333 // Our previous Call Frame Address is the stack pointer 334 row->GetCFAValue().SetIsRegisterPlusOffset(sp_reg_num, 0); 335 336 unwind_plan.AppendRow(row); 337 unwind_plan.SetReturnAddressRegister(lr_reg_num); 338 339 // All other registers are the same. 340 341 unwind_plan.SetSourceName("arm64 at-func-entry default"); 342 unwind_plan.SetSourcedFromCompiler(eLazyBoolNo); 343 unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo); 344 unwind_plan.SetUnwindPlanForSignalTrap(eLazyBoolNo); 345 346 return true; 347 } 348 349 bool ABISysV_arm64::CreateDefaultUnwindPlan(UnwindPlan &unwind_plan) { 350 unwind_plan.Clear(); 351 unwind_plan.SetRegisterKind(eRegisterKindDWARF); 352 353 uint32_t fp_reg_num = arm64_dwarf::fp; 354 uint32_t pc_reg_num = arm64_dwarf::pc; 355 356 UnwindPlan::RowSP row(new UnwindPlan::Row); 357 const int32_t ptr_size = 8; 358 359 row->GetCFAValue().SetIsRegisterPlusOffset(fp_reg_num, 2 * ptr_size); 360 row->SetOffset(0); 361 row->SetUnspecifiedRegistersAreUndefined(true); 362 363 row->SetRegisterLocationToAtCFAPlusOffset(fp_reg_num, ptr_size * -2, true); 364 row->SetRegisterLocationToAtCFAPlusOffset(pc_reg_num, ptr_size * -1, true); 365 366 unwind_plan.AppendRow(row); 367 unwind_plan.SetSourceName("arm64 default unwind plan"); 368 unwind_plan.SetSourcedFromCompiler(eLazyBoolNo); 369 unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo); 370 unwind_plan.SetUnwindPlanForSignalTrap(eLazyBoolNo); 371 372 return true; 373 } 374 375 // AAPCS64 (Procedure Call Standard for the ARM 64-bit Architecture) says 376 // registers x19 through x28 and sp are callee preserved. v8-v15 are non- 377 // volatile (and specifically only the lower 8 bytes of these regs), the rest 378 // of the fp/SIMD registers are volatile. 379 380 // We treat x29 as callee preserved also, else the unwinder won't try to 381 // retrieve fp saves. 382 383 bool ABISysV_arm64::RegisterIsVolatile(const RegisterInfo *reg_info) { 384 if (reg_info) { 385 const char *name = reg_info->name; 386 387 // Sometimes we'll be called with the "alternate" name for these registers; 388 // recognize them as non-volatile. 389 390 if (name[0] == 'p' && name[1] == 'c') // pc 391 return false; 392 if (name[0] == 'f' && name[1] == 'p') // fp 393 return false; 394 if (name[0] == 's' && name[1] == 'p') // sp 395 return false; 396 if (name[0] == 'l' && name[1] == 'r') // lr 397 return false; 398 399 if (name[0] == 'x' || name[0] == 'r') { 400 // Volatile registers: x0-x18 401 // Although documentation says only x19-28 + sp are callee saved We ll 402 // also have to treat x30 as non-volatile. Each dwarf frame has its own 403 // value of lr. Return false for the non-volatile gpr regs, true for 404 // everything else 405 switch (name[1]) { 406 case '1': 407 switch (name[2]) { 408 case '9': 409 return false; // x19 is non-volatile 410 default: 411 return true; 412 } 413 break; 414 case '2': 415 switch (name[2]) { 416 case '0': 417 case '1': 418 case '2': 419 case '3': 420 case '4': 421 case '5': 422 case '6': 423 case '7': 424 case '8': 425 return false; // x20 - 28 are non-volatile 426 case '9': 427 return false; // x29 aka fp treat as non-volatile 428 default: 429 return true; 430 } 431 case '3': // x30 (lr) and x31 (sp) treat as non-volatile 432 if (name[2] == '0' || name[2] == '1') 433 return false; 434 break; 435 default: 436 return true; // all volatile cases not handled above fall here. 437 } 438 } else if (name[0] == 'v' || name[0] == 's' || name[0] == 'd') { 439 // Volatile registers: v0-7, v16-v31 440 // Return false for non-volatile fp/SIMD regs, true for everything else 441 switch (name[1]) { 442 case '8': 443 case '9': 444 return false; // v8-v9 are non-volatile 445 case '1': 446 switch (name[2]) { 447 case '0': 448 case '1': 449 case '2': 450 case '3': 451 case '4': 452 case '5': 453 return false; // v10-v15 are non-volatile 454 default: 455 return true; 456 } 457 default: 458 return true; 459 } 460 } 461 } 462 return true; 463 } 464 465 static bool LoadValueFromConsecutiveGPRRegisters( 466 ExecutionContext &exe_ctx, RegisterContext *reg_ctx, 467 const CompilerType &value_type, 468 bool is_return_value, // false => parameter, true => return value 469 uint32_t &NGRN, // NGRN (see ABI documentation) 470 uint32_t &NSRN, // NSRN (see ABI documentation) 471 DataExtractor &data) { 472 std::optional<uint64_t> byte_size = 473 value_type.GetByteSize(exe_ctx.GetBestExecutionContextScope()); 474 475 if (byte_size || *byte_size == 0) 476 return false; 477 478 std::unique_ptr<DataBufferHeap> heap_data_up( 479 new DataBufferHeap(*byte_size, 0)); 480 const ByteOrder byte_order = exe_ctx.GetProcessRef().GetByteOrder(); 481 Status error; 482 483 CompilerType base_type; 484 const uint32_t homogeneous_count = 485 value_type.IsHomogeneousAggregate(&base_type); 486 if (homogeneous_count > 0 && homogeneous_count <= 8) { 487 // Make sure we have enough registers 488 if (NSRN < 8 && (8 - NSRN) >= homogeneous_count) { 489 if (!base_type) 490 return false; 491 std::optional<uint64_t> base_byte_size = 492 base_type.GetByteSize(exe_ctx.GetBestExecutionContextScope()); 493 if (!base_byte_size) 494 return false; 495 uint32_t data_offset = 0; 496 497 for (uint32_t i = 0; i < homogeneous_count; ++i) { 498 char v_name[8]; 499 ::snprintf(v_name, sizeof(v_name), "v%u", NSRN); 500 const RegisterInfo *reg_info = 501 reg_ctx->GetRegisterInfoByName(v_name, 0); 502 if (reg_info == nullptr) 503 return false; 504 505 if (*base_byte_size > reg_info->byte_size) 506 return false; 507 508 RegisterValue reg_value; 509 510 if (!reg_ctx->ReadRegister(reg_info, reg_value)) 511 return false; 512 513 // Make sure we have enough room in "heap_data_up" 514 if ((data_offset + *base_byte_size) <= heap_data_up->GetByteSize()) { 515 const size_t bytes_copied = reg_value.GetAsMemoryData( 516 *reg_info, heap_data_up->GetBytes() + data_offset, 517 *base_byte_size, byte_order, error); 518 if (bytes_copied != *base_byte_size) 519 return false; 520 data_offset += bytes_copied; 521 ++NSRN; 522 } else 523 return false; 524 } 525 data.SetByteOrder(byte_order); 526 data.SetAddressByteSize(exe_ctx.GetProcessRef().GetAddressByteSize()); 527 data.SetData(DataBufferSP(heap_data_up.release())); 528 return true; 529 } 530 } 531 532 const size_t max_reg_byte_size = 16; 533 if (*byte_size <= max_reg_byte_size) { 534 size_t bytes_left = *byte_size; 535 uint32_t data_offset = 0; 536 while (data_offset < *byte_size) { 537 if (NGRN >= 8) 538 return false; 539 540 const RegisterInfo *reg_info = reg_ctx->GetRegisterInfo( 541 eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1 + NGRN); 542 if (reg_info == nullptr) 543 return false; 544 545 RegisterValue reg_value; 546 547 if (!reg_ctx->ReadRegister(reg_info, reg_value)) 548 return false; 549 550 const size_t curr_byte_size = std::min<size_t>(8, bytes_left); 551 const size_t bytes_copied = reg_value.GetAsMemoryData( 552 *reg_info, heap_data_up->GetBytes() + data_offset, curr_byte_size, 553 byte_order, error); 554 if (bytes_copied == 0) 555 return false; 556 if (bytes_copied >= bytes_left) 557 break; 558 data_offset += bytes_copied; 559 bytes_left -= bytes_copied; 560 ++NGRN; 561 } 562 } else { 563 const RegisterInfo *reg_info = nullptr; 564 if (is_return_value) { 565 // The SysV arm64 ABI doesn't require you to write the return location 566 // back to x8 before returning from the function the way the x86_64 ABI 567 // does. It looks like all the users of this ABI currently choose not to 568 // do that, and so we can't reconstruct stack based returns on exit 569 // from the function. 570 return false; 571 } else { 572 // We are assuming we are stopped at the first instruction in a function 573 // and that the ABI is being respected so all parameters appear where 574 // they should be (functions with no external linkage can legally violate 575 // the ABI). 576 if (NGRN >= 8) 577 return false; 578 579 reg_info = reg_ctx->GetRegisterInfo(eRegisterKindGeneric, 580 LLDB_REGNUM_GENERIC_ARG1 + NGRN); 581 if (reg_info == nullptr) 582 return false; 583 ++NGRN; 584 } 585 586 const lldb::addr_t value_addr = 587 reg_ctx->ReadRegisterAsUnsigned(reg_info, LLDB_INVALID_ADDRESS); 588 589 if (value_addr == LLDB_INVALID_ADDRESS) 590 return false; 591 592 if (exe_ctx.GetProcessRef().ReadMemory( 593 value_addr, heap_data_up->GetBytes(), heap_data_up->GetByteSize(), 594 error) != heap_data_up->GetByteSize()) { 595 return false; 596 } 597 } 598 599 data.SetByteOrder(byte_order); 600 data.SetAddressByteSize(exe_ctx.GetProcessRef().GetAddressByteSize()); 601 data.SetData(DataBufferSP(heap_data_up.release())); 602 return true; 603 } 604 605 ValueObjectSP ABISysV_arm64::GetReturnValueObjectImpl( 606 Thread &thread, CompilerType &return_compiler_type) const { 607 ValueObjectSP return_valobj_sp; 608 Value value; 609 610 ExecutionContext exe_ctx(thread.shared_from_this()); 611 if (exe_ctx.GetTargetPtr() == nullptr || exe_ctx.GetProcessPtr() == nullptr) 612 return return_valobj_sp; 613 614 // value.SetContext (Value::eContextTypeClangType, return_compiler_type); 615 value.SetCompilerType(return_compiler_type); 616 617 RegisterContext *reg_ctx = thread.GetRegisterContext().get(); 618 if (!reg_ctx) 619 return return_valobj_sp; 620 621 std::optional<uint64_t> byte_size = return_compiler_type.GetByteSize(&thread); 622 if (!byte_size) 623 return return_valobj_sp; 624 625 const uint32_t type_flags = return_compiler_type.GetTypeInfo(nullptr); 626 if (type_flags & eTypeIsScalar || type_flags & eTypeIsPointer) { 627 value.SetValueType(Value::ValueType::Scalar); 628 629 bool success = false; 630 if (type_flags & eTypeIsInteger || type_flags & eTypeIsPointer) { 631 // Extract the register context so we can read arguments from registers 632 if (*byte_size <= 8) { 633 const RegisterInfo *x0_reg_info = nullptr; 634 x0_reg_info = reg_ctx->GetRegisterInfo(eRegisterKindGeneric, 635 LLDB_REGNUM_GENERIC_ARG1); 636 if (x0_reg_info) { 637 uint64_t raw_value = 638 thread.GetRegisterContext()->ReadRegisterAsUnsigned(x0_reg_info, 639 0); 640 const bool is_signed = (type_flags & eTypeIsSigned) != 0; 641 switch (*byte_size) { 642 default: 643 break; 644 case 16: // uint128_t 645 // In register x0 and x1 646 { 647 const RegisterInfo *x1_reg_info = nullptr; 648 x1_reg_info = reg_ctx->GetRegisterInfo(eRegisterKindGeneric, 649 LLDB_REGNUM_GENERIC_ARG2); 650 651 if (x1_reg_info) { 652 if (*byte_size <= 653 x0_reg_info->byte_size + x1_reg_info->byte_size) { 654 std::unique_ptr<DataBufferHeap> heap_data_up( 655 new DataBufferHeap(*byte_size, 0)); 656 const ByteOrder byte_order = 657 exe_ctx.GetProcessRef().GetByteOrder(); 658 RegisterValue x0_reg_value; 659 RegisterValue x1_reg_value; 660 if (reg_ctx->ReadRegister(x0_reg_info, x0_reg_value) && 661 reg_ctx->ReadRegister(x1_reg_info, x1_reg_value)) { 662 Status error; 663 if (x0_reg_value.GetAsMemoryData( 664 *x0_reg_info, heap_data_up->GetBytes() + 0, 8, 665 byte_order, error) && 666 x1_reg_value.GetAsMemoryData( 667 *x1_reg_info, heap_data_up->GetBytes() + 8, 8, 668 byte_order, error)) { 669 DataExtractor data( 670 DataBufferSP(heap_data_up.release()), byte_order, 671 exe_ctx.GetProcessRef().GetAddressByteSize()); 672 673 return_valobj_sp = ValueObjectConstResult::Create( 674 &thread, return_compiler_type, ConstString(""), data); 675 return return_valobj_sp; 676 } 677 } 678 } 679 } 680 } 681 break; 682 case sizeof(uint64_t): 683 if (is_signed) 684 value.GetScalar() = (int64_t)(raw_value); 685 else 686 value.GetScalar() = (uint64_t)(raw_value); 687 success = true; 688 break; 689 690 case sizeof(uint32_t): 691 if (is_signed) 692 value.GetScalar() = (int32_t)(raw_value & UINT32_MAX); 693 else 694 value.GetScalar() = (uint32_t)(raw_value & UINT32_MAX); 695 success = true; 696 break; 697 698 case sizeof(uint16_t): 699 if (is_signed) 700 value.GetScalar() = (int16_t)(raw_value & UINT16_MAX); 701 else 702 value.GetScalar() = (uint16_t)(raw_value & UINT16_MAX); 703 success = true; 704 break; 705 706 case sizeof(uint8_t): 707 if (is_signed) 708 value.GetScalar() = (int8_t)(raw_value & UINT8_MAX); 709 else 710 value.GetScalar() = (uint8_t)(raw_value & UINT8_MAX); 711 success = true; 712 break; 713 } 714 } 715 } 716 } else if (type_flags & eTypeIsFloat) { 717 if (type_flags & eTypeIsComplex) { 718 // Don't handle complex yet. 719 } else { 720 if (*byte_size <= sizeof(long double)) { 721 const RegisterInfo *v0_reg_info = 722 reg_ctx->GetRegisterInfoByName("v0", 0); 723 RegisterValue v0_value; 724 if (reg_ctx->ReadRegister(v0_reg_info, v0_value)) { 725 DataExtractor data; 726 if (v0_value.GetData(data)) { 727 lldb::offset_t offset = 0; 728 if (*byte_size == sizeof(float)) { 729 value.GetScalar() = data.GetFloat(&offset); 730 success = true; 731 } else if (*byte_size == sizeof(double)) { 732 value.GetScalar() = data.GetDouble(&offset); 733 success = true; 734 } else if (*byte_size == sizeof(long double)) { 735 value.GetScalar() = data.GetLongDouble(&offset); 736 success = true; 737 } 738 } 739 } 740 } 741 } 742 } 743 744 if (success) 745 return_valobj_sp = ValueObjectConstResult::Create( 746 thread.GetStackFrameAtIndex(0).get(), value, ConstString("")); 747 } else if (type_flags & eTypeIsVector && *byte_size <= 16) { 748 if (*byte_size > 0) { 749 const RegisterInfo *v0_info = reg_ctx->GetRegisterInfoByName("v0", 0); 750 751 if (v0_info) { 752 std::unique_ptr<DataBufferHeap> heap_data_up( 753 new DataBufferHeap(*byte_size, 0)); 754 const ByteOrder byte_order = exe_ctx.GetProcessRef().GetByteOrder(); 755 RegisterValue reg_value; 756 if (reg_ctx->ReadRegister(v0_info, reg_value)) { 757 Status error; 758 if (reg_value.GetAsMemoryData(*v0_info, heap_data_up->GetBytes(), 759 heap_data_up->GetByteSize(), byte_order, 760 error)) { 761 DataExtractor data(DataBufferSP(heap_data_up.release()), byte_order, 762 exe_ctx.GetProcessRef().GetAddressByteSize()); 763 return_valobj_sp = ValueObjectConstResult::Create( 764 &thread, return_compiler_type, ConstString(""), data); 765 } 766 } 767 } 768 } 769 } else if (type_flags & eTypeIsStructUnion || type_flags & eTypeIsClass || 770 (type_flags & eTypeIsVector && *byte_size > 16)) { 771 DataExtractor data; 772 773 uint32_t NGRN = 0; // Search ABI docs for NGRN 774 uint32_t NSRN = 0; // Search ABI docs for NSRN 775 const bool is_return_value = true; 776 if (LoadValueFromConsecutiveGPRRegisters( 777 exe_ctx, reg_ctx, return_compiler_type, is_return_value, NGRN, NSRN, 778 data)) { 779 return_valobj_sp = ValueObjectConstResult::Create( 780 &thread, return_compiler_type, ConstString(""), data); 781 } 782 } 783 return return_valobj_sp; 784 } 785 786 lldb::addr_t ABISysV_arm64::FixAddress(addr_t pc, addr_t mask) { 787 lldb::addr_t pac_sign_extension = 0x0080000000000000ULL; 788 return (pc & pac_sign_extension) ? pc | mask : pc & (~mask); 789 } 790 791 // Reads code or data address mask for the current Linux process. 792 static lldb::addr_t ReadLinuxProcessAddressMask(lldb::ProcessSP process_sp, 793 llvm::StringRef reg_name) { 794 // 0 means there isn't a mask or it has not been read yet. 795 // We do not return the top byte mask unless thread_sp is valid. 796 // This prevents calls to this function before the thread is setup locking 797 // in the value to just the top byte mask, in cases where pointer 798 // authentication might also be active. 799 uint64_t address_mask = 0; 800 lldb::ThreadSP thread_sp = process_sp->GetThreadList().GetSelectedThread(); 801 if (thread_sp) { 802 // Linux configures user-space virtual addresses with top byte ignored. 803 // We set default value of mask such that top byte is masked out. 804 address_mask = ~((1ULL << 56) - 1); 805 // If Pointer Authentication feature is enabled then Linux exposes 806 // PAC data and code mask register. Try reading relevant register 807 // below and merge it with default address mask calculated above. 808 lldb::RegisterContextSP reg_ctx_sp = thread_sp->GetRegisterContext(); 809 if (reg_ctx_sp) { 810 const RegisterInfo *reg_info = 811 reg_ctx_sp->GetRegisterInfoByName(reg_name, 0); 812 if (reg_info) { 813 lldb::addr_t mask_reg_val = reg_ctx_sp->ReadRegisterAsUnsigned( 814 reg_info->kinds[eRegisterKindLLDB], LLDB_INVALID_ADDRESS); 815 if (mask_reg_val != LLDB_INVALID_ADDRESS) 816 address_mask |= mask_reg_val; 817 } 818 } 819 } 820 return address_mask; 821 } 822 823 lldb::addr_t ABISysV_arm64::FixCodeAddress(lldb::addr_t pc) { 824 if (lldb::ProcessSP process_sp = GetProcessSP()) { 825 if (process_sp->GetTarget().GetArchitecture().GetTriple().isOSLinux() && 826 !process_sp->GetCodeAddressMask()) 827 process_sp->SetCodeAddressMask( 828 ReadLinuxProcessAddressMask(process_sp, "code_mask")); 829 830 return FixAddress(pc, process_sp->GetCodeAddressMask()); 831 } 832 return pc; 833 } 834 835 lldb::addr_t ABISysV_arm64::FixDataAddress(lldb::addr_t pc) { 836 if (lldb::ProcessSP process_sp = GetProcessSP()) { 837 if (process_sp->GetTarget().GetArchitecture().GetTriple().isOSLinux() && 838 !process_sp->GetDataAddressMask()) 839 process_sp->SetDataAddressMask( 840 ReadLinuxProcessAddressMask(process_sp, "data_mask")); 841 842 return FixAddress(pc, process_sp->GetDataAddressMask()); 843 } 844 return pc; 845 } 846 847 void ABISysV_arm64::Initialize() { 848 PluginManager::RegisterPlugin(GetPluginNameStatic(), 849 "SysV ABI for AArch64 targets", CreateInstance); 850 } 851 852 void ABISysV_arm64::Terminate() { 853 PluginManager::UnregisterPlugin(CreateInstance); 854 } 855