lldb/source/Core/Value.cpp

   1 //===-- Value.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 "lldb/Core/Value.h"
  10
  11 #include "lldb/Core/Address.h"
  12 #include "lldb/Core/Module.h"
  13 #include "lldb/Symbol/CompilerType.h"
  14 #include "lldb/Symbol/ObjectFile.h"
  15 #include "lldb/Symbol/SymbolContext.h"
  16 #include "lldb/Symbol/Type.h"
  17 #include "lldb/Symbol/Variable.h"
  18 #include "lldb/Target/ExecutionContext.h"
  19 #include "lldb/Target/Process.h"
  20 #include "lldb/Target/SectionLoadList.h"
  21 #include "lldb/Target/Target.h"
  22 #include "lldb/Utility/ConstString.h"
  23 #include "lldb/Utility/DataBufferHeap.h"
  24 #include "lldb/Utility/DataExtractor.h"
  25 #include "lldb/Utility/Endian.h"
  26 #include "lldb/Utility/FileSpec.h"
  27 #include "lldb/Utility/State.h"
  28 #include "lldb/Utility/Stream.h"
  29 #include "lldb/lldb-defines.h"
  30 #include "lldb/lldb-forward.h"
  31 #include "lldb/lldb-types.h"
  32
  33 #include <memory>
  34 #include <optional>
  35 #include <string>
  36
  37 #include <cinttypes>
  38
  39 using namespace lldb;
  40 using namespace lldb_private;
  41
  42 Value::Value() : m_value(), m_compiler_type(), m_data_buffer() {}
  43
  44 Value::Value(const Scalar &scalar)
  45     : m_value(scalar), m_compiler_type(), m_data_buffer() {}
  46
  47 Value::Value(const void *bytes, int len)
  48     : m_value(), m_compiler_type(), m_value_type(ValueType::HostAddress),
  49       m_data_buffer() {
  50   SetBytes(bytes, len);
  51 }
  52
  53 Value::Value(const Value &v)
  54     : m_value(v.m_value), m_compiler_type(v.m_compiler_type),
  55       m_context(v.m_context), m_value_type(v.m_value_type),
  56       m_context_type(v.m_context_type), m_data_buffer() {
  57   const uintptr_t rhs_value =
  58       (uintptr_t)v.m_value.ULongLong(LLDB_INVALID_ADDRESS);
  59   if ((rhs_value != 0) &&
  60       (rhs_value == (uintptr_t)v.m_data_buffer.GetBytes())) {
  61     m_data_buffer.CopyData(v.m_data_buffer.GetBytes(),
  62                            v.m_data_buffer.GetByteSize());
  63
  64     m_value = (uintptr_t)m_data_buffer.GetBytes();
  65   }
  66 }
  67
  68 Value &Value::operator=(const Value &rhs) {
  69   if (this != &rhs) {
  70     m_value = rhs.m_value;
  71     m_compiler_type = rhs.m_compiler_type;
  72     m_context = rhs.m_context;
  73     m_value_type = rhs.m_value_type;
  74     m_context_type = rhs.m_context_type;
  75     const uintptr_t rhs_value =
  76         (uintptr_t)rhs.m_value.ULongLong(LLDB_INVALID_ADDRESS);
  77     if ((rhs_value != 0) &&
  78         (rhs_value == (uintptr_t)rhs.m_data_buffer.GetBytes())) {
  79       m_data_buffer.CopyData(rhs.m_data_buffer.GetBytes(),
  80                              rhs.m_data_buffer.GetByteSize());
  81
  82       m_value = (uintptr_t)m_data_buffer.GetBytes();
  83     }
  84   }
  85   return *this;
  86 }
  87
  88 void Value::SetBytes(const void *bytes, int len) {
  89   m_value_type = ValueType::HostAddress;
  90   m_data_buffer.CopyData(bytes, len);
  91   m_value = (uintptr_t)m_data_buffer.GetBytes();
  92 }
  93
  94 void Value::AppendBytes(const void *bytes, int len) {
  95   m_value_type = ValueType::HostAddress;
  96   m_data_buffer.AppendData(bytes, len);
  97   m_value = (uintptr_t)m_data_buffer.GetBytes();
  98 }
  99
 100 void Value::Dump(Stream *strm) {
 101   if (!strm)
 102     return;
 103   m_value.GetValue(*strm, true);
 104   strm->Printf(", value_type = %s, context = %p, context_type = %s",
 105                Value::GetValueTypeAsCString(m_value_type), m_context,
 106                Value::GetContextTypeAsCString(m_context_type));
 107 }
 108
 109 Value::ValueType Value::GetValueType() const { return m_value_type; }
 110
 111 AddressType Value::GetValueAddressType() const {
 112   switch (m_value_type) {
 113   case ValueType::Invalid:
 114   case ValueType::Scalar:
 115     break;
 116   case ValueType::LoadAddress:
 117     return eAddressTypeLoad;
 118   case ValueType::FileAddress:
 119     return eAddressTypeFile;
 120   case ValueType::HostAddress:
 121     return eAddressTypeHost;
 122   }
 123   return eAddressTypeInvalid;
 124 }
 125
 126 Value::ValueType Value::GetValueTypeFromAddressType(AddressType address_type) {
 127   switch (address_type) {
 128     case eAddressTypeFile:
 129       return Value::ValueType::FileAddress;
 130     case eAddressTypeLoad:
 131       return Value::ValueType::LoadAddress;
 132     case eAddressTypeHost:
 133       return Value::ValueType::HostAddress;
 134     case eAddressTypeInvalid:
 135       return Value::ValueType::Invalid;
 136   }
 137   llvm_unreachable("Unexpected address type!");
 138 }
 139
 140 RegisterInfo *Value::GetRegisterInfo() const {
 141   if (m_context_type == ContextType::RegisterInfo)
 142     return static_cast<RegisterInfo *>(m_context);
 143   return nullptr;
 144 }
 145
 146 Type *Value::GetType() {
 147   if (m_context_type == ContextType::LLDBType)
 148     return static_cast<Type *>(m_context);
 149   return nullptr;
 150 }
 151
 152 size_t Value::AppendDataToHostBuffer(const Value &rhs) {
 153   if (this == &rhs)
 154     return 0;
 155
 156   size_t curr_size = m_data_buffer.GetByteSize();
 157   Status error;
 158   switch (rhs.GetValueType()) {
 159   case ValueType::Invalid:
 160     return 0;
 161   case ValueType::Scalar: {
 162     const size_t scalar_size = rhs.m_value.GetByteSize();
 163     if (scalar_size > 0) {
 164       const size_t new_size = curr_size + scalar_size;
 165       if (ResizeData(new_size) == new_size) {
 166         rhs.m_value.GetAsMemoryData(m_data_buffer.GetBytes() + curr_size,
 167                                     scalar_size, endian::InlHostByteOrder(),
 168                                     error);
 169         return scalar_size;
 170       }
 171     }
 172   } break;
 173   case ValueType::FileAddress:
 174   case ValueType::LoadAddress:
 175   case ValueType::HostAddress: {
 176     const uint8_t *src = rhs.GetBuffer().GetBytes();
 177     const size_t src_len = rhs.GetBuffer().GetByteSize();
 178     if (src && src_len > 0) {
 179       const size_t new_size = curr_size + src_len;
 180       if (ResizeData(new_size) == new_size) {
 181         ::memcpy(m_data_buffer.GetBytes() + curr_size, src, src_len);
 182         return src_len;
 183       }
 184     }
 185   } break;
 186   }
 187   return 0;
 188 }
 189
 190 size_t Value::ResizeData(size_t len) {
 191   m_value_type = ValueType::HostAddress;
 192   m_data_buffer.SetByteSize(len);
 193   m_value = (uintptr_t)m_data_buffer.GetBytes();
 194   return m_data_buffer.GetByteSize();
 195 }
 196
 197 bool Value::ValueOf(ExecutionContext *exe_ctx) {
 198   switch (m_context_type) {
 199   case ContextType::Invalid:
 200   case ContextType::RegisterInfo: // RegisterInfo *
 201   case ContextType::LLDBType:     // Type *
 202     break;
 203
 204   case ContextType::Variable: // Variable *
 205     ResolveValue(exe_ctx);
 206     return true;
 207   }
 208   return false;
 209 }
 210
 211 uint64_t Value::GetValueByteSize(Status *error_ptr, ExecutionContext *exe_ctx) {
 212   switch (m_context_type) {
 213   case ContextType::RegisterInfo: // RegisterInfo *
 214     if (GetRegisterInfo()) {
 215       if (error_ptr)
 216         error_ptr->Clear();
 217       return GetRegisterInfo()->byte_size;
 218     }
 219     break;
 220
 221   case ContextType::Invalid:
 222   case ContextType::LLDBType: // Type *
 223   case ContextType::Variable: // Variable *
 224   {
 225     auto *scope = exe_ctx ? exe_ctx->GetBestExecutionContextScope() : nullptr;
 226     if (std::optional<uint64_t> size = GetCompilerType().GetByteSize(scope)) {
 227       if (error_ptr)
 228         error_ptr->Clear();
 229       return *size;
 230     }
 231     break;
 232   }
 233   }
 234   if (error_ptr && error_ptr->Success())
 235     error_ptr->SetErrorString("Unable to determine byte size.");
 236   return 0;
 237 }
 238
 239 const CompilerType &Value::GetCompilerType() {
 240   if (!m_compiler_type.IsValid()) {
 241     switch (m_context_type) {
 242     case ContextType::Invalid:
 243       break;
 244
 245     case ContextType::RegisterInfo:
 246       break; // TODO: Eventually convert into a compiler type?
 247
 248     case ContextType::LLDBType: {
 249       Type *lldb_type = GetType();
 250       if (lldb_type)
 251         m_compiler_type = lldb_type->GetForwardCompilerType();
 252     } break;
 253
 254     case ContextType::Variable: {
 255       Variable *variable = GetVariable();
 256       if (variable) {
 257         Type *variable_type = variable->GetType();
 258         if (variable_type)
 259           m_compiler_type = variable_type->GetForwardCompilerType();
 260       }
 261     } break;
 262     }
 263   }
 264
 265   return m_compiler_type;
 266 }
 267
 268 void Value::SetCompilerType(const CompilerType &compiler_type) {
 269   m_compiler_type = compiler_type;
 270 }
 271
 272 lldb::Format Value::GetValueDefaultFormat() {
 273   switch (m_context_type) {
 274   case ContextType::RegisterInfo:
 275     if (GetRegisterInfo())
 276       return GetRegisterInfo()->format;
 277     break;
 278
 279   case ContextType::Invalid:
 280   case ContextType::LLDBType:
 281   case ContextType::Variable: {
 282     const CompilerType &ast_type = GetCompilerType();
 283     if (ast_type.IsValid())
 284       return ast_type.GetFormat();
 285   } break;
 286   }
 287
 288   // Return a good default in case we can't figure anything out
 289   return eFormatHex;
 290 }
 291
 292 bool Value::GetData(DataExtractor &data) {
 293   switch (m_value_type) {
 294   case ValueType::Invalid:
 295     return false;
 296   case ValueType::Scalar:
 297     if (m_value.GetData(data))
 298       return true;
 299     break;
 300
 301   case ValueType::LoadAddress:
 302   case ValueType::FileAddress:
 303   case ValueType::HostAddress:
 304     if (m_data_buffer.GetByteSize()) {
 305       data.SetData(m_data_buffer.GetBytes(), m_data_buffer.GetByteSize(),
 306                    data.GetByteOrder());
 307       return true;
 308     }
 309     break;
 310   }
 311
 312   return false;
 313 }
 314
 315 Status Value::GetValueAsData(ExecutionContext *exe_ctx, DataExtractor &data,
 316                              Module *module) {
 317   data.Clear();
 318
 319   Status error;
 320   lldb::addr_t address = LLDB_INVALID_ADDRESS;
 321   AddressType address_type = eAddressTypeFile;
 322   Address file_so_addr;
 323   const CompilerType &ast_type = GetCompilerType();
 324   std::optional<uint64_t> type_size = ast_type.GetByteSize(
 325       exe_ctx ? exe_ctx->GetBestExecutionContextScope() : nullptr);
 326   // Nothing to be done for a zero-sized type.
 327   if (type_size && *type_size == 0)
 328     return error;
 329
 330   switch (m_value_type) {
 331   case ValueType::Invalid:
 332     error.SetErrorString("invalid value");
 333     break;
 334   case ValueType::Scalar: {
 335     data.SetByteOrder(endian::InlHostByteOrder());
 336     if (ast_type.IsValid())
 337       data.SetAddressByteSize(ast_type.GetPointerByteSize());
 338     else
 339       data.SetAddressByteSize(sizeof(void *));
 340
 341     uint32_t limit_byte_size = UINT32_MAX;
 342
 343     if (type_size)
 344       limit_byte_size = *type_size;
 345
 346     if (limit_byte_size <= m_value.GetByteSize()) {
 347       if (m_value.GetData(data, limit_byte_size))
 348         return error; // Success;
 349     }
 350
 351     error.SetErrorString("extracting data from value failed");
 352     break;
 353   }
 354   case ValueType::LoadAddress:
 355     if (exe_ctx == nullptr) {
 356       error.SetErrorString("can't read load address (no execution context)");
 357     } else {
 358       Process *process = exe_ctx->GetProcessPtr();
 359       if (process == nullptr || !process->IsAlive()) {
 360         Target *target = exe_ctx->GetTargetPtr();
 361         if (target) {
 362           // Allow expressions to run and evaluate things when the target has
 363           // memory sections loaded. This allows you to use "target modules
 364           // load" to load your executable and any shared libraries, then
 365           // execute commands where you can look at types in data sections.
 366           const SectionLoadList &target_sections = target->GetSectionLoadList();
 367           if (!target_sections.IsEmpty()) {
 368             address = m_value.ULongLong(LLDB_INVALID_ADDRESS);
 369             if (target_sections.ResolveLoadAddress(address, file_so_addr)) {
 370               address_type = eAddressTypeLoad;
 371               data.SetByteOrder(target->GetArchitecture().GetByteOrder());
 372               data.SetAddressByteSize(
 373                   target->GetArchitecture().GetAddressByteSize());
 374             } else
 375               address = LLDB_INVALID_ADDRESS;
 376           }
 377         } else {
 378           error.SetErrorString("can't read load address (invalid process)");
 379         }
 380       } else {
 381         address = m_value.ULongLong(LLDB_INVALID_ADDRESS);
 382         address_type = eAddressTypeLoad;
 383         data.SetByteOrder(
 384             process->GetTarget().GetArchitecture().GetByteOrder());
 385         data.SetAddressByteSize(
 386             process->GetTarget().GetArchitecture().GetAddressByteSize());
 387       }
 388     }
 389     break;
 390
 391   case ValueType::FileAddress:
 392     if (exe_ctx == nullptr) {
 393       error.SetErrorString("can't read file address (no execution context)");
 394     } else if (exe_ctx->GetTargetPtr() == nullptr) {
 395       error.SetErrorString("can't read file address (invalid target)");
 396     } else {
 397       address = m_value.ULongLong(LLDB_INVALID_ADDRESS);
 398       if (address == LLDB_INVALID_ADDRESS) {
 399         error.SetErrorString("invalid file address");
 400       } else {
 401         if (module == nullptr) {
 402           // The only thing we can currently lock down to a module so that we
 403           // can resolve a file address, is a variable.
 404           Variable *variable = GetVariable();
 405           if (variable) {
 406             SymbolContext var_sc;
 407             variable->CalculateSymbolContext(&var_sc);
 408             module = var_sc.module_sp.get();
 409           }
 410         }
 411
 412         if (module) {
 413           bool resolved = false;
 414           ObjectFile *objfile = module->GetObjectFile();
 415           if (objfile) {
 416             Address so_addr(address, objfile->GetSectionList());
 417             addr_t load_address =
 418                 so_addr.GetLoadAddress(exe_ctx->GetTargetPtr());
 419             bool process_launched_and_stopped =
 420                 exe_ctx->GetProcessPtr()
 421                     ? StateIsStoppedState(exe_ctx->GetProcessPtr()->GetState(),
 422                                           true /* must_exist */)
 423                     : false;
 424             // Don't use the load address if the process has exited.
 425             if (load_address != LLDB_INVALID_ADDRESS &&
 426                 process_launched_and_stopped) {
 427               resolved = true;
 428               address = load_address;
 429               address_type = eAddressTypeLoad;
 430               data.SetByteOrder(
 431                   exe_ctx->GetTargetRef().GetArchitecture().GetByteOrder());
 432               data.SetAddressByteSize(exe_ctx->GetTargetRef()
 433                                           .GetArchitecture()
 434                                           .GetAddressByteSize());
 435             } else {
 436               if (so_addr.IsSectionOffset()) {
 437                 resolved = true;
 438                 file_so_addr = so_addr;
 439                 data.SetByteOrder(objfile->GetByteOrder());
 440                 data.SetAddressByteSize(objfile->GetAddressByteSize());
 441               }
 442             }
 443           }
 444           if (!resolved) {
 445             Variable *variable = GetVariable();
 446
 447             if (module) {
 448               if (variable)
 449                 error.SetErrorStringWithFormat(
 450                     "unable to resolve the module for file address 0x%" PRIx64
 451                     " for variable '%s' in %s",
 452                     address, variable->GetName().AsCString(""),
 453                     module->GetFileSpec().GetPath().c_str());
 454               else
 455                 error.SetErrorStringWithFormat(
 456                     "unable to resolve the module for file address 0x%" PRIx64
 457                     " in %s",
 458                     address, module->GetFileSpec().GetPath().c_str());
 459             } else {
 460               if (variable)
 461                 error.SetErrorStringWithFormat(
 462                     "unable to resolve the module for file address 0x%" PRIx64
 463                     " for variable '%s'",
 464                     address, variable->GetName().AsCString(""));
 465               else
 466                 error.SetErrorStringWithFormat(
 467                     "unable to resolve the module for file address 0x%" PRIx64,
 468                     address);
 469             }
 470           }
 471         } else {
 472           // Can't convert a file address to anything valid without more
 473           // context (which Module it came from)
 474           error.SetErrorString(
 475               "can't read memory from file address without more context");
 476         }
 477       }
 478     }
 479     break;
 480
 481   case ValueType::HostAddress:
 482     address = m_value.ULongLong(LLDB_INVALID_ADDRESS);
 483     address_type = eAddressTypeHost;
 484     if (exe_ctx) {
 485       Target *target = exe_ctx->GetTargetPtr();
 486       if (target) {
 487         data.SetByteOrder(target->GetArchitecture().GetByteOrder());
 488         data.SetAddressByteSize(target->GetArchitecture().GetAddressByteSize());
 489         break;
 490       }
 491     }
 492     // fallback to host settings
 493     data.SetByteOrder(endian::InlHostByteOrder());
 494     data.SetAddressByteSize(sizeof(void *));
 495     break;
 496   }
 497
 498   // Bail if we encountered any errors
 499   if (error.Fail())
 500     return error;
 501
 502   if (address == LLDB_INVALID_ADDRESS) {
 503     error.SetErrorStringWithFormat("invalid %s address",
 504                                    address_type == eAddressTypeHost ? "host"
 505                                                                     : "load");
 506     return error;
 507   }
 508
 509   // If we got here, we need to read the value from memory.
 510   size_t byte_size = GetValueByteSize(&error, exe_ctx);
 511
 512   // Bail if we encountered any errors getting the byte size.
 513   if (error.Fail())
 514     return error;
 515
 516   // No memory to read for zero-sized types.
 517   if (byte_size == 0)
 518     return error;
 519
 520   // Make sure we have enough room within "data", and if we don't make
 521   // something large enough that does
 522   if (!data.ValidOffsetForDataOfSize(0, byte_size)) {
 523     auto data_sp = std::make_shared<DataBufferHeap>(byte_size, '\0');
 524     data.SetData(data_sp);
 525   }
 526
 527   uint8_t *dst = const_cast<uint8_t *>(data.PeekData(0, byte_size));
 528   if (dst != nullptr) {
 529     if (address_type == eAddressTypeHost) {
 530       // The address is an address in this process, so just copy it.
 531       if (address == 0) {
 532         error.SetErrorString("trying to read from host address of 0.");
 533         return error;
 534       }
 535       memcpy(dst, reinterpret_cast<uint8_t *>(address), byte_size);
 536     } else if ((address_type == eAddressTypeLoad) ||
 537                (address_type == eAddressTypeFile)) {
 538       if (file_so_addr.IsValid()) {
 539         const bool force_live_memory = true;
 540         if (exe_ctx->GetTargetRef().ReadMemory(file_so_addr, dst, byte_size,
 541                                                error, force_live_memory) !=
 542             byte_size) {
 543           error.SetErrorStringWithFormat(
 544               "read memory from 0x%" PRIx64 " failed", (uint64_t)address);
 545         }
 546       } else {
 547         // The execution context might have a NULL process, but it might have a
 548         // valid process in the exe_ctx->target, so use the
 549         // ExecutionContext::GetProcess accessor to ensure we get the process
 550         // if there is one.
 551         Process *process = exe_ctx->GetProcessPtr();
 552
 553         if (process) {
 554           const size_t bytes_read =
 555               process->ReadMemory(address, dst, byte_size, error);
 556           if (bytes_read != byte_size)
 557             error.SetErrorStringWithFormat(
 558                 "read memory from 0x%" PRIx64 " failed (%u of %u bytes read)",
 559                 (uint64_t)address, (uint32_t)bytes_read, (uint32_t)byte_size);
 560         } else {
 561           error.SetErrorStringWithFormat("read memory from 0x%" PRIx64
 562                                          " failed (invalid process)",
 563                                          (uint64_t)address);
 564         }
 565       }
 566     } else {
 567       error.SetErrorStringWithFormat("unsupported AddressType value (%i)",
 568                                      address_type);
 569     }
 570   } else {
 571     error.SetErrorString("out of memory");
 572   }
 573
 574   return error;
 575 }
 576
 577 Scalar &Value::ResolveValue(ExecutionContext *exe_ctx, Module *module) {
 578   const CompilerType &compiler_type = GetCompilerType();
 579   if (compiler_type.IsValid()) {
 580     switch (m_value_type) {
 581     case ValueType::Invalid:
 582     case ValueType::Scalar: // raw scalar value
 583       break;
 584
 585     case ValueType::FileAddress:
 586     case ValueType::LoadAddress: // load address value
 587     case ValueType::HostAddress: // host address value (for memory in the process
 588                                 // that is using liblldb)
 589     {
 590       DataExtractor data;
 591       lldb::addr_t addr = m_value.ULongLong(LLDB_INVALID_ADDRESS);
 592       Status error(GetValueAsData(exe_ctx, data, module));
 593       if (error.Success()) {
 594         Scalar scalar;
 595         if (compiler_type.GetValueAsScalar(
 596                 data, 0, data.GetByteSize(), scalar,
 597                 exe_ctx ? exe_ctx->GetBestExecutionContextScope() : nullptr)) {
 598           m_value = scalar;
 599           m_value_type = ValueType::Scalar;
 600         } else {
 601           if ((uintptr_t)addr != (uintptr_t)m_data_buffer.GetBytes()) {
 602             m_value.Clear();
 603             m_value_type = ValueType::Scalar;
 604           }
 605         }
 606       } else {
 607         if ((uintptr_t)addr != (uintptr_t)m_data_buffer.GetBytes()) {
 608           m_value.Clear();
 609           m_value_type = ValueType::Scalar;
 610         }
 611       }
 612     } break;
 613     }
 614   }
 615   return m_value;
 616 }
 617
 618 Variable *Value::GetVariable() {
 619   if (m_context_type == ContextType::Variable)
 620     return static_cast<Variable *>(m_context);
 621   return nullptr;
 622 }
 623
 624 void Value::Clear() {
 625   m_value.Clear();
 626   m_compiler_type.Clear();
 627   m_value_type = ValueType::Scalar;
 628   m_context = nullptr;
 629   m_context_type = ContextType::Invalid;
 630   m_data_buffer.Clear();
 631 }
 632
 633 const char *Value::GetValueTypeAsCString(ValueType value_type) {
 634   switch (value_type) {
 635   case ValueType::Invalid:
 636     return "invalid";
 637   case ValueType::Scalar:
 638     return "scalar";
 639   case ValueType::FileAddress:
 640     return "file address";
 641   case ValueType::LoadAddress:
 642     return "load address";
 643   case ValueType::HostAddress:
 644     return "host address";
 645   };
 646   llvm_unreachable("enum cases exhausted.");
 647 }
 648
 649 const char *Value::GetContextTypeAsCString(ContextType context_type) {
 650   switch (context_type) {
 651   case ContextType::Invalid:
 652     return "invalid";
 653   case ContextType::RegisterInfo:
 654     return "RegisterInfo *";
 655   case ContextType::LLDBType:
 656     return "Type *";
 657   case ContextType::Variable:
 658     return "Variable *";
 659   };
 660   llvm_unreachable("enum cases exhausted.");
 661 }
 662
 663 void Value::ConvertToLoadAddress(Module *module, Target *target) {
 664   if (!module || !target || (GetValueType() != ValueType::FileAddress))
 665     return;
 666
 667   lldb::addr_t file_addr = GetScalar().ULongLong(LLDB_INVALID_ADDRESS);
 668   if (file_addr == LLDB_INVALID_ADDRESS)
 669     return;
 670
 671   Address so_addr;
 672   if (!module->ResolveFileAddress(file_addr, so_addr))
 673     return;
 674   lldb::addr_t load_addr = so_addr.GetLoadAddress(target);
 675   if (load_addr == LLDB_INVALID_ADDRESS)
 676     return;
 677
 678   SetValueType(Value::ValueType::LoadAddress);
 679   GetScalar() = load_addr;
 680 }
 681
 682 void ValueList::PushValue(const Value &value) { m_values.push_back(value); }
 683
 684 size_t ValueList::GetSize() { return m_values.size(); }
 685
 686 Value *ValueList::GetValueAtIndex(size_t idx) {
 687   if (idx < GetSize()) {
 688     return &(m_values[idx]);
 689   } else
 690     return nullptr;
 691 }
 692
 693 void ValueList::Clear() { m_values.clear(); }