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1//===------ MachOPlatform.cpp - Utilities for executing MachO in Orc ------===//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-exception6//7//===----------------------------------------------------------------------===//8 9#include "llvm/ExecutionEngine/Orc/MachOPlatform.h"10 11#include "llvm/BinaryFormat/MachO.h"12#include "llvm/ExecutionEngine/JITLink/EHFrameSupport.h"13#include "llvm/ExecutionEngine/JITLink/MachO.h"14#include "llvm/ExecutionEngine/JITLink/aarch64.h"15#include "llvm/ExecutionEngine/JITLink/x86_64.h"16#include "llvm/ExecutionEngine/Orc/AbsoluteSymbols.h"17#include "llvm/ExecutionEngine/Orc/ExecutionUtils.h"18#include "llvm/ExecutionEngine/Orc/MachOBuilder.h"19#include "llvm/Support/Debug.h"20#include <optional>21 22#define DEBUG_TYPE "orc"23 24using namespace llvm;25using namespace llvm::orc;26using namespace llvm::orc::shared;27 28namespace llvm {29namespace orc {30namespace shared {31 32using SPSMachOJITDylibDepInfo = SPSTuple<bool, SPSSequence<SPSExecutorAddr>>;33using SPSMachOJITDylibDepInfoMap =34    SPSSequence<SPSTuple<SPSExecutorAddr, SPSMachOJITDylibDepInfo>>;35 36class SPSMachOExecutorSymbolFlags;37 38template <>39class SPSSerializationTraits<SPSMachOJITDylibDepInfo,40                             MachOPlatform::MachOJITDylibDepInfo> {41public:42  static size_t size(const MachOPlatform::MachOJITDylibDepInfo &DDI) {43    return SPSMachOJITDylibDepInfo::AsArgList::size(DDI.Sealed, DDI.DepHeaders);44  }45 46  static bool serialize(SPSOutputBuffer &OB,47                        const MachOPlatform::MachOJITDylibDepInfo &DDI) {48    return SPSMachOJITDylibDepInfo::AsArgList::serialize(OB, DDI.Sealed,49                                                         DDI.DepHeaders);50  }51 52  static bool deserialize(SPSInputBuffer &IB,53                          MachOPlatform::MachOJITDylibDepInfo &DDI) {54    return SPSMachOJITDylibDepInfo::AsArgList::deserialize(IB, DDI.Sealed,55                                                           DDI.DepHeaders);56  }57};58 59template <>60class SPSSerializationTraits<SPSMachOExecutorSymbolFlags,61                             MachOPlatform::MachOExecutorSymbolFlags> {62private:63  using UT = std::underlying_type_t<MachOPlatform::MachOExecutorSymbolFlags>;64 65public:66  static size_t size(const MachOPlatform::MachOExecutorSymbolFlags &SF) {67    return sizeof(UT);68  }69 70  static bool serialize(SPSOutputBuffer &OB,71                        const MachOPlatform::MachOExecutorSymbolFlags &SF) {72    return SPSArgList<UT>::serialize(OB, static_cast<UT>(SF));73  }74 75  static bool deserialize(SPSInputBuffer &IB,76                          MachOPlatform::MachOExecutorSymbolFlags &SF) {77    UT Tmp;78    if (!SPSArgList<UT>::deserialize(IB, Tmp))79      return false;80    SF = static_cast<MachOPlatform::MachOExecutorSymbolFlags>(Tmp);81    return true;82  }83};84 85} // namespace shared86} // namespace orc87} // namespace llvm88 89namespace {90 91using SPSRegisterSymbolsArgs =92    SPSArgList<SPSExecutorAddr,93               SPSSequence<SPSTuple<SPSExecutorAddr, SPSExecutorAddr,94                                    SPSMachOExecutorSymbolFlags>>>;95 96std::unique_ptr<jitlink::LinkGraph> createPlatformGraph(MachOPlatform &MOP,97                                                        std::string Name) {98  auto &ES = MOP.getExecutionSession();99  return std::make_unique<jitlink::LinkGraph>(100      std::move(Name), ES.getSymbolStringPool(), ES.getTargetTriple(),101      SubtargetFeatures(), jitlink::getGenericEdgeKindName);102}103 104// Creates a Bootstrap-Complete LinkGraph to run deferred actions.105class MachOPlatformCompleteBootstrapMaterializationUnit106    : public MaterializationUnit {107public:108  using SymbolTableVector =109      SmallVector<std::tuple<ExecutorAddr, ExecutorAddr,110                             MachOPlatform::MachOExecutorSymbolFlags>>;111 112  MachOPlatformCompleteBootstrapMaterializationUnit(113      MachOPlatform &MOP, StringRef PlatformJDName,114      SymbolStringPtr CompleteBootstrapSymbol, SymbolTableVector SymTab,115      shared::AllocActions DeferredAAs, ExecutorAddr MachOHeaderAddr,116      ExecutorAddr PlatformBootstrap, ExecutorAddr PlatformShutdown,117      ExecutorAddr RegisterJITDylib, ExecutorAddr DeregisterJITDylib,118      ExecutorAddr RegisterObjectSymbolTable,119      ExecutorAddr DeregisterObjectSymbolTable)120      : MaterializationUnit(121            {{{CompleteBootstrapSymbol, JITSymbolFlags::None}}, nullptr}),122        MOP(MOP), PlatformJDName(PlatformJDName),123        CompleteBootstrapSymbol(std::move(CompleteBootstrapSymbol)),124        SymTab(std::move(SymTab)), DeferredAAs(std::move(DeferredAAs)),125        MachOHeaderAddr(MachOHeaderAddr), PlatformBootstrap(PlatformBootstrap),126        PlatformShutdown(PlatformShutdown), RegisterJITDylib(RegisterJITDylib),127        DeregisterJITDylib(DeregisterJITDylib),128        RegisterObjectSymbolTable(RegisterObjectSymbolTable),129        DeregisterObjectSymbolTable(DeregisterObjectSymbolTable) {}130 131  StringRef getName() const override {132    return "MachOPlatformCompleteBootstrap";133  }134 135  void materialize(std::unique_ptr<MaterializationResponsibility> R) override {136    using namespace jitlink;137    auto G = createPlatformGraph(MOP, "<OrcRTCompleteBootstrap>");138    auto &PlaceholderSection =139        G->createSection("__orc_rt_cplt_bs", MemProt::Read);140    auto &PlaceholderBlock =141        G->createZeroFillBlock(PlaceholderSection, 1, ExecutorAddr(), 1, 0);142    G->addDefinedSymbol(PlaceholderBlock, 0, *CompleteBootstrapSymbol, 1,143                        Linkage::Strong, Scope::Hidden, false, true);144 145    // Reserve space for the stolen actions, plus two extras.146    G->allocActions().reserve(DeferredAAs.size() + 3);147 148    // 1. Bootstrap the platform support code.149    G->allocActions().push_back(150        {cantFail(WrapperFunctionCall::Create<SPSArgList<>>(PlatformBootstrap)),151         cantFail(152             WrapperFunctionCall::Create<SPSArgList<>>(PlatformShutdown))});153 154    // 2. Register the platform JITDylib.155    G->allocActions().push_back(156        {cantFail(WrapperFunctionCall::Create<157                  SPSArgList<SPSString, SPSExecutorAddr>>(158             RegisterJITDylib, PlatformJDName, MachOHeaderAddr)),159         cantFail(WrapperFunctionCall::Create<SPSArgList<SPSExecutorAddr>>(160             DeregisterJITDylib, MachOHeaderAddr))});161 162    // 3. Register deferred symbols.163    G->allocActions().push_back(164        {cantFail(WrapperFunctionCall::Create<SPSRegisterSymbolsArgs>(165             RegisterObjectSymbolTable, MachOHeaderAddr, SymTab)),166         cantFail(WrapperFunctionCall::Create<SPSRegisterSymbolsArgs>(167             DeregisterObjectSymbolTable, MachOHeaderAddr, SymTab))});168 169    // 4. Add the deferred actions to the graph.170    std::move(DeferredAAs.begin(), DeferredAAs.end(),171              std::back_inserter(G->allocActions()));172 173    MOP.getObjectLinkingLayer().emit(std::move(R), std::move(G));174  }175 176  void discard(const JITDylib &JD, const SymbolStringPtr &Sym) override {}177 178private:179  MachOPlatform &MOP;180  StringRef PlatformJDName;181  SymbolStringPtr CompleteBootstrapSymbol;182  SymbolTableVector SymTab;183  shared::AllocActions DeferredAAs;184  ExecutorAddr MachOHeaderAddr;185  ExecutorAddr PlatformBootstrap;186  ExecutorAddr PlatformShutdown;187  ExecutorAddr RegisterJITDylib;188  ExecutorAddr DeregisterJITDylib;189  ExecutorAddr RegisterObjectSymbolTable;190  ExecutorAddr DeregisterObjectSymbolTable;191};192 193static StringRef ObjCRuntimeObjectSectionsData[] = {194    MachOObjCCatListSectionName,   MachOObjCCatList2SectionName,195    MachOObjCClassListSectionName, MachOObjCClassRefsSectionName,196    MachOObjCConstSectionName,     MachOObjCDataSectionName,197    MachOObjCProtoListSectionName, MachOObjCProtoRefsSectionName,198    MachOObjCNLCatListSectionName, MachOObjCNLClassListSectionName,199    MachOObjCSelRefsSectionName};200 201static StringRef ObjCRuntimeObjectSectionsText[] = {202    MachOObjCClassNameSectionName, MachOObjCMethNameSectionName,203    MachOObjCMethTypeSectionName,  MachOSwift5TypesSectionName,204    MachOSwift5TypeRefSectionName, MachOSwift5FieldMetadataSectionName,205    MachOSwift5EntrySectionName,   MachOSwift5ProtoSectionName,206    MachOSwift5ProtosSectionName};207 208static StringRef ObjCRuntimeObjectSectionName =209    "__llvm_jitlink_ObjCRuntimeRegistrationObject";210 211static StringRef ObjCImageInfoSymbolName =212    "__llvm_jitlink_macho_objc_imageinfo";213 214struct ObjCImageInfoFlags {215  uint16_t SwiftABIVersion;216  uint16_t SwiftVersion;217  bool HasCategoryClassProperties;218  bool HasSignedObjCClassROs;219 220  static constexpr uint32_t SIGNED_CLASS_RO = (1 << 4);221  static constexpr uint32_t HAS_CATEGORY_CLASS_PROPERTIES = (1 << 6);222 223  explicit ObjCImageInfoFlags(uint32_t RawFlags) {224    HasSignedObjCClassROs = RawFlags & SIGNED_CLASS_RO;225    HasCategoryClassProperties = RawFlags & HAS_CATEGORY_CLASS_PROPERTIES;226    SwiftABIVersion = (RawFlags >> 8) & 0xFF;227    SwiftVersion = (RawFlags >> 16) & 0xFFFF;228  }229 230  uint32_t rawFlags() const {231    uint32_t Result = 0;232    if (HasCategoryClassProperties)233      Result |= HAS_CATEGORY_CLASS_PROPERTIES;234    if (HasSignedObjCClassROs)235      Result |= SIGNED_CLASS_RO;236    Result |= (SwiftABIVersion << 8);237    Result |= (SwiftVersion << 16);238    return Result;239  }240};241} // end anonymous namespace242 243namespace llvm {244namespace orc {245 246std::optional<MachOPlatform::HeaderOptions::BuildVersionOpts>247MachOPlatform::HeaderOptions::BuildVersionOpts::fromTriple(const Triple &TT,248                                                           uint32_t MinOS,249                                                           uint32_t SDK) {250 251  uint32_t Platform;252  switch (TT.getOS()) {253  case Triple::IOS:254    Platform = TT.isSimulatorEnvironment() ? MachO::PLATFORM_IOSSIMULATOR255                                           : MachO::PLATFORM_IOS;256    break;257  case Triple::MacOSX:258    Platform = MachO::PLATFORM_MACOS;259    break;260  case Triple::TvOS:261    Platform = TT.isSimulatorEnvironment() ? MachO::PLATFORM_TVOSSIMULATOR262                                           : MachO::PLATFORM_TVOS;263    break;264  case Triple::WatchOS:265    Platform = TT.isSimulatorEnvironment() ? MachO::PLATFORM_WATCHOSSIMULATOR266                                           : MachO::PLATFORM_WATCHOS;267    break;268  case Triple::XROS:269    Platform = TT.isSimulatorEnvironment() ? MachO::PLATFORM_XROS_SIMULATOR270                                           : MachO::PLATFORM_XROS;271    break;272  default:273    return std::nullopt;274  }275 276  return MachOPlatform::HeaderOptions::BuildVersionOpts{Platform, MinOS, SDK};277}278 279Expected<std::unique_ptr<MachOPlatform>>280MachOPlatform::Create(ObjectLinkingLayer &ObjLinkingLayer, JITDylib &PlatformJD,281                      std::unique_ptr<DefinitionGenerator> OrcRuntime,282                      HeaderOptions PlatformJDOpts,283                      MachOHeaderMUBuilder BuildMachOHeaderMU,284                      std::optional<SymbolAliasMap> RuntimeAliases) {285 286  auto &ES = ObjLinkingLayer.getExecutionSession();287 288  // If the target is not supported then bail out immediately.289  if (!supportedTarget(ES.getTargetTriple()))290    return make_error<StringError>("Unsupported MachOPlatform triple: " +291                                       ES.getTargetTriple().str(),292                                   inconvertibleErrorCode());293 294  auto &EPC = ES.getExecutorProcessControl();295 296  // Create default aliases if the caller didn't supply any.297  if (!RuntimeAliases)298    RuntimeAliases = standardPlatformAliases(ES);299 300  // Define the aliases.301  if (auto Err = PlatformJD.define(symbolAliases(std::move(*RuntimeAliases))))302    return std::move(Err);303 304  // Add JIT-dispatch function support symbols.305  if (auto Err = PlatformJD.define(306          absoluteSymbols({{ES.intern("___orc_rt_jit_dispatch"),307                            {EPC.getJITDispatchInfo().JITDispatchFunction,308                             JITSymbolFlags::Exported}},309                           {ES.intern("___orc_rt_jit_dispatch_ctx"),310                            {EPC.getJITDispatchInfo().JITDispatchContext,311                             JITSymbolFlags::Exported}}})))312    return std::move(Err);313 314  // Create the instance.315  Error Err = Error::success();316  auto P = std::unique_ptr<MachOPlatform>(new MachOPlatform(317      ObjLinkingLayer, PlatformJD, std::move(OrcRuntime),318      std::move(PlatformJDOpts), std::move(BuildMachOHeaderMU), Err));319  if (Err)320    return std::move(Err);321  return std::move(P);322}323 324Expected<std::unique_ptr<MachOPlatform>>325MachOPlatform::Create(ObjectLinkingLayer &ObjLinkingLayer, JITDylib &PlatformJD,326                      const char *OrcRuntimePath, HeaderOptions PlatformJDOpts,327                      MachOHeaderMUBuilder BuildMachOHeaderMU,328                      std::optional<SymbolAliasMap> RuntimeAliases) {329 330  // Create a generator for the ORC runtime archive.331  auto OrcRuntimeArchiveGenerator =332      StaticLibraryDefinitionGenerator::Load(ObjLinkingLayer, OrcRuntimePath);333  if (!OrcRuntimeArchiveGenerator)334    return OrcRuntimeArchiveGenerator.takeError();335 336  return Create(ObjLinkingLayer, PlatformJD,337                std::move(*OrcRuntimeArchiveGenerator),338                std::move(PlatformJDOpts), std::move(BuildMachOHeaderMU),339                std::move(RuntimeAliases));340}341 342Error MachOPlatform::setupJITDylib(JITDylib &JD) {343  return setupJITDylib(JD, /*Opts=*/{});344}345 346Error MachOPlatform::setupJITDylib(JITDylib &JD, HeaderOptions Opts) {347  if (auto Err = JD.define(BuildMachOHeaderMU(*this, std::move(Opts))))348    return Err;349 350  return ES.lookup({&JD}, MachOHeaderStartSymbol).takeError();351}352 353Error MachOPlatform::teardownJITDylib(JITDylib &JD) {354  std::lock_guard<std::mutex> Lock(PlatformMutex);355  auto I = JITDylibToHeaderAddr.find(&JD);356  if (I != JITDylibToHeaderAddr.end()) {357    assert(HeaderAddrToJITDylib.count(I->second) &&358           "HeaderAddrToJITDylib missing entry");359    HeaderAddrToJITDylib.erase(I->second);360    JITDylibToHeaderAddr.erase(I);361  }362  JITDylibToPThreadKey.erase(&JD);363  return Error::success();364}365 366Error MachOPlatform::notifyAdding(ResourceTracker &RT,367                                  const MaterializationUnit &MU) {368  auto &JD = RT.getJITDylib();369  const auto &InitSym = MU.getInitializerSymbol();370  if (!InitSym)371    return Error::success();372 373  RegisteredInitSymbols[&JD].add(InitSym,374                                 SymbolLookupFlags::WeaklyReferencedSymbol);375  LLVM_DEBUG({376    dbgs() << "MachOPlatform: Registered init symbol " << *InitSym << " for MU "377           << MU.getName() << "\n";378  });379  return Error::success();380}381 382Error MachOPlatform::notifyRemoving(ResourceTracker &RT) {383  llvm_unreachable("Not supported yet");384}385 386static void addAliases(ExecutionSession &ES, SymbolAliasMap &Aliases,387                       ArrayRef<std::pair<const char *, const char *>> AL) {388  for (auto &KV : AL) {389    auto AliasName = ES.intern(KV.first);390    assert(!Aliases.count(AliasName) && "Duplicate symbol name in alias map");391    Aliases[std::move(AliasName)] = {ES.intern(KV.second),392                                     JITSymbolFlags::Exported};393  }394}395 396SymbolAliasMap MachOPlatform::standardPlatformAliases(ExecutionSession &ES) {397  SymbolAliasMap Aliases;398  addAliases(ES, Aliases, requiredCXXAliases());399  addAliases(ES, Aliases, standardRuntimeUtilityAliases());400  addAliases(ES, Aliases, standardLazyCompilationAliases());401  return Aliases;402}403 404ArrayRef<std::pair<const char *, const char *>>405MachOPlatform::requiredCXXAliases() {406  static const std::pair<const char *, const char *> RequiredCXXAliases[] = {407      {"___cxa_atexit", "___orc_rt_macho_cxa_atexit"}};408 409  return ArrayRef<std::pair<const char *, const char *>>(RequiredCXXAliases);410}411 412ArrayRef<std::pair<const char *, const char *>>413MachOPlatform::standardRuntimeUtilityAliases() {414  static const std::pair<const char *, const char *>415      StandardRuntimeUtilityAliases[] = {416          {"___orc_rt_run_program", "___orc_rt_macho_run_program"},417          {"___orc_rt_jit_dlerror", "___orc_rt_macho_jit_dlerror"},418          {"___orc_rt_jit_dlopen", "___orc_rt_macho_jit_dlopen"},419          {"___orc_rt_jit_dlupdate", "___orc_rt_macho_jit_dlupdate"},420          {"___orc_rt_jit_dlclose", "___orc_rt_macho_jit_dlclose"},421          {"___orc_rt_jit_dlsym", "___orc_rt_macho_jit_dlsym"},422          {"___orc_rt_log_error", "___orc_rt_log_error_to_stderr"}};423 424  return ArrayRef<std::pair<const char *, const char *>>(425      StandardRuntimeUtilityAliases);426}427 428ArrayRef<std::pair<const char *, const char *>>429MachOPlatform::standardLazyCompilationAliases() {430  static const std::pair<const char *, const char *>431      StandardLazyCompilationAliases[] = {432          {"__orc_rt_reenter", "__orc_rt_sysv_reenter"},433          {"__orc_rt_resolve_tag", "___orc_rt_resolve_tag"}};434 435  return ArrayRef<std::pair<const char *, const char *>>(436      StandardLazyCompilationAliases);437}438 439bool MachOPlatform::supportedTarget(const Triple &TT) {440  switch (TT.getArch()) {441  case Triple::aarch64:442  case Triple::x86_64:443    return true;444  default:445    return false;446  }447}448 449jitlink::Edge::Kind MachOPlatform::getPointerEdgeKind(jitlink::LinkGraph &G) {450  switch (G.getTargetTriple().getArch()) {451  case Triple::aarch64:452    return jitlink::aarch64::Pointer64;453  case Triple::x86_64:454    return jitlink::x86_64::Pointer64;455  default:456    llvm_unreachable("Unsupported architecture");457  }458}459 460MachOPlatform::MachOExecutorSymbolFlags461MachOPlatform::flagsForSymbol(jitlink::Symbol &Sym) {462  MachOPlatform::MachOExecutorSymbolFlags Flags{};463  if (Sym.getLinkage() == jitlink::Linkage::Weak)464    Flags |= MachOExecutorSymbolFlags::Weak;465 466  if (Sym.isCallable())467    Flags |= MachOExecutorSymbolFlags::Callable;468 469  return Flags;470}471 472MachOPlatform::MachOPlatform(473    ObjectLinkingLayer &ObjLinkingLayer, JITDylib &PlatformJD,474    std::unique_ptr<DefinitionGenerator> OrcRuntimeGenerator,475    HeaderOptions PlatformJDOpts, MachOHeaderMUBuilder BuildMachOHeaderMU,476    Error &Err)477    : ES(ObjLinkingLayer.getExecutionSession()), PlatformJD(PlatformJD),478      ObjLinkingLayer(ObjLinkingLayer),479      BuildMachOHeaderMU(std::move(BuildMachOHeaderMU)) {480  ErrorAsOutParameter _(Err);481  ObjLinkingLayer.addPlugin(std::make_unique<MachOPlatformPlugin>(*this));482  PlatformJD.addGenerator(std::move(OrcRuntimeGenerator));483 484  {485    // Check for force-eh-frame486    std::optional<bool> ForceEHFrames;487    if ((Err = ES.getBootstrapMapValue<bool, bool>("darwin-use-ehframes-only",488                                                   ForceEHFrames)))489      return;490    this->ForceEHFrames = ForceEHFrames.value_or(false);491  }492 493  BootstrapInfo BI;494  Bootstrap = &BI;495 496  // Bootstrap process -- here be phase-ordering dragons.497  //498  // The MachOPlatform class uses allocation actions to register metadata499  // sections with the ORC runtime, however the runtime contains metadata500  // registration functions that have their own metadata that they need to501  // register (e.g. the frame-info registration functions have frame-info).502  // We can't use an ordinary lookup to find these registration functions503  // because their address is needed during the link of the containing graph504  // itself (to build the allocation actions that will call the registration505  // functions). Further complicating the situation (a) the graph containing506  // the registration functions is allowed to depend on other graphs (e.g. the507  // graph containing the ORC runtime RTTI support) so we need to handle an508  // unknown set of dependencies during bootstrap, and (b) these graphs may509  // be linked concurrently if the user has installed a concurrent dispatcher.510  //511  // We satisfy these constraints by implementing a bootstrap phase during which512  // allocation actions generated by MachOPlatform are appended to a list of513  // deferred allocation actions, rather than to the graphs themselves. At the514  // end of the bootstrap process the deferred actions are attached to a final515  // "complete-bootstrap" graph that causes them to be run.516  //517  // The bootstrap steps are as follows:518  //519  // 1. Request the graph containing the mach header. This graph is guaranteed520  //    not to have any metadata so the fact that the registration functions521  //    are not available yet is not a problem.522  //523  // 2. Look up the registration functions and discard the results. This will524  //    trigger linking of the graph containing these functions, and525  //    consequently any graphs that it depends on. We do not use the lookup526  //    result to find the addresses of the functions requested (as described527  //    above the lookup will return too late for that), instead we capture the528  //    addresses in a post-allocation pass injected by the platform runtime529  //    during bootstrap only.530  //531  // 3. During bootstrap the MachOPlatformPlugin keeps a count of the number of532  //    graphs being linked (potentially concurrently), and we block until all533  //    of these graphs have completed linking. This is to avoid a race on the534  //    deferred-actions vector: the lookup for the runtime registration535  //    functions may return while some functions (those that are being536  //    incidentally linked in, but aren't reachable via the runtime functions)537  //    are still being linked, and we need to capture any allocation actions538  //    for this incidental code before we proceed.539  //540  // 4. Once all active links are complete we transfer the deferred actions to541  //    a newly added CompleteBootstrap graph and then request a symbol from542  //    the CompleteBootstrap graph to trigger materialization. This will cause543  //    all deferred actions to be run, and once this lookup returns we can544  //    proceed.545  //546  // 5. Finally, we associate runtime support methods in MachOPlatform with547  //    the corresponding jit-dispatch tag variables in the ORC runtime to make548  //    the support methods callable. The bootstrap is now complete.549 550  // Step (1) Add header materialization unit and request.551  if ((Err = PlatformJD.define(552           this->BuildMachOHeaderMU(*this, std::move(PlatformJDOpts)))))553    return;554  if ((Err = ES.lookup(&PlatformJD, MachOHeaderStartSymbol).takeError()))555    return;556 557  // Step (2) Request runtime registration functions to trigger558  // materialization..559  if ((Err = ES.lookup(makeJITDylibSearchOrder(&PlatformJD),560                       SymbolLookupSet(561                           {PlatformBootstrap.Name, PlatformShutdown.Name,562                            RegisterJITDylib.Name, DeregisterJITDylib.Name,563                            RegisterObjectSymbolTable.Name,564                            DeregisterObjectSymbolTable.Name,565                            RegisterObjectPlatformSections.Name,566                            DeregisterObjectPlatformSections.Name,567                            CreatePThreadKey.Name}))568                 .takeError()))569    return;570 571  // Step (3) Wait for any incidental linker work to complete.572  {573    std::unique_lock<std::mutex> Lock(PlatformMutex);574    BI.CV.wait(Lock, [&]() { return BI.ActiveGraphs == 0; });575    Bootstrap = nullptr;576  }577 578  // Step (4) Add complete-bootstrap materialization unit and request.579  auto BootstrapCompleteSymbol = ES.intern("__orc_rt_macho_complete_bootstrap");580  if ((Err = PlatformJD.define(581           std::make_unique<MachOPlatformCompleteBootstrapMaterializationUnit>(582               *this, PlatformJD.getName(), BootstrapCompleteSymbol,583               std::move(BI.SymTab), std::move(BI.DeferredAAs),584               BI.MachOHeaderAddr, PlatformBootstrap.Addr,585               PlatformShutdown.Addr, RegisterJITDylib.Addr,586               DeregisterJITDylib.Addr, RegisterObjectSymbolTable.Addr,587               DeregisterObjectSymbolTable.Addr))))588    return;589  if ((Err = ES.lookup(makeJITDylibSearchOrder(590                           &PlatformJD, JITDylibLookupFlags::MatchAllSymbols),591                       std::move(BootstrapCompleteSymbol))592                 .takeError()))593    return;594 595  // (5) Associate runtime support functions.596  // TODO: Consider moving this above (4) to make runtime support functions597  //       available to the bootstrap completion graph. We'd just need to be598  //       sure that the runtime support functions are fully usable before any599  //       bootstrap completion actions use them (e.g. the ORC runtime600  //       macho_platform object would have to have been created and601  //       initialized).602  if ((Err = associateRuntimeSupportFunctions()))603    return;604}605 606Error MachOPlatform::associateRuntimeSupportFunctions() {607  ExecutionSession::JITDispatchHandlerAssociationMap WFs;608 609  using PushInitializersSPSSig =610      SPSExpected<SPSMachOJITDylibDepInfoMap>(SPSExecutorAddr);611  WFs[ES.intern("___orc_rt_macho_push_initializers_tag")] =612      ES.wrapAsyncWithSPS<PushInitializersSPSSig>(613          this, &MachOPlatform::rt_pushInitializers);614 615  using PushSymbolsSPSSig =616      SPSError(SPSExecutorAddr, SPSSequence<SPSTuple<SPSString, bool>>);617  WFs[ES.intern("___orc_rt_macho_push_symbols_tag")] =618      ES.wrapAsyncWithSPS<PushSymbolsSPSSig>(this,619                                             &MachOPlatform::rt_pushSymbols);620 621  return ES.registerJITDispatchHandlers(PlatformJD, std::move(WFs));622}623 624void MachOPlatform::pushInitializersLoop(625    PushInitializersSendResultFn SendResult, JITDylibSP JD) {626  DenseMap<JITDylib *, SymbolLookupSet> NewInitSymbols;627  DenseMap<JITDylib *, SmallVector<JITDylib *>> JDDepMap;628  SmallVector<JITDylib *, 16> Worklist({JD.get()});629 630  ES.runSessionLocked([&]() {631    while (!Worklist.empty()) {632      // FIXME: Check for defunct dylibs.633 634      auto DepJD = Worklist.back();635      Worklist.pop_back();636 637      // If we've already visited this JITDylib on this iteration then continue.638      auto [It, Inserted] = JDDepMap.try_emplace(DepJD);639      if (!Inserted)640        continue;641 642      // Add dep info.643      auto &DM = It->second;644      DepJD->withLinkOrderDo([&](const JITDylibSearchOrder &O) {645        for (auto &KV : O) {646          if (KV.first == DepJD)647            continue;648          DM.push_back(KV.first);649          Worklist.push_back(KV.first);650        }651      });652 653      // Add any registered init symbols.654      auto RISItr = RegisteredInitSymbols.find(DepJD);655      if (RISItr != RegisteredInitSymbols.end()) {656        NewInitSymbols[DepJD] = std::move(RISItr->second);657        RegisteredInitSymbols.erase(RISItr);658      }659    }660  });661 662  // If there are no further init symbols to look up then send the link order663  // (as a list of header addresses) to the caller.664  if (NewInitSymbols.empty()) {665 666    // To make the list intelligible to the runtime we need to convert all667    // JITDylib pointers to their header addresses. Only include JITDylibs668    // that appear in the JITDylibToHeaderAddr map (i.e. those that have been669    // through setupJITDylib) -- bare JITDylibs aren't managed by the platform.670    DenseMap<JITDylib *, ExecutorAddr> HeaderAddrs;671    HeaderAddrs.reserve(JDDepMap.size());672    {673      std::lock_guard<std::mutex> Lock(PlatformMutex);674      for (auto &KV : JDDepMap) {675        auto I = JITDylibToHeaderAddr.find(KV.first);676        if (I != JITDylibToHeaderAddr.end())677          HeaderAddrs[KV.first] = I->second;678      }679    }680 681    // Build the dep info map to return.682    MachOJITDylibDepInfoMap DIM;683    DIM.reserve(JDDepMap.size());684    for (auto &KV : JDDepMap) {685      auto HI = HeaderAddrs.find(KV.first);686      // Skip unmanaged JITDylibs.687      if (HI == HeaderAddrs.end())688        continue;689      auto H = HI->second;690      MachOJITDylibDepInfo DepInfo;691      for (auto &Dep : KV.second) {692        auto HJ = HeaderAddrs.find(Dep);693        if (HJ != HeaderAddrs.end())694          DepInfo.DepHeaders.push_back(HJ->second);695      }696      DIM.push_back(std::make_pair(H, std::move(DepInfo)));697    }698    SendResult(DIM);699    return;700  }701 702  // Otherwise issue a lookup and re-run this phase when it completes.703  lookupInitSymbolsAsync(704      [this, SendResult = std::move(SendResult), JD](Error Err) mutable {705        if (Err)706          SendResult(std::move(Err));707        else708          pushInitializersLoop(std::move(SendResult), JD);709      },710      ES, std::move(NewInitSymbols));711}712 713void MachOPlatform::rt_pushInitializers(PushInitializersSendResultFn SendResult,714                                        ExecutorAddr JDHeaderAddr) {715  JITDylibSP JD;716  {717    std::lock_guard<std::mutex> Lock(PlatformMutex);718    auto I = HeaderAddrToJITDylib.find(JDHeaderAddr);719    if (I != HeaderAddrToJITDylib.end())720      JD = I->second;721  }722 723  LLVM_DEBUG({724    dbgs() << "MachOPlatform::rt_pushInitializers(" << JDHeaderAddr << ") ";725    if (JD)726      dbgs() << "pushing initializers for " << JD->getName() << "\n";727    else728      dbgs() << "No JITDylib for header address.\n";729  });730 731  if (!JD) {732    SendResult(make_error<StringError>("No JITDylib with header addr " +733                                           formatv("{0:x}", JDHeaderAddr),734                                       inconvertibleErrorCode()));735    return;736  }737 738  pushInitializersLoop(std::move(SendResult), JD);739}740 741void MachOPlatform::rt_pushSymbols(742    PushSymbolsInSendResultFn SendResult, ExecutorAddr Handle,743    const std::vector<std::pair<StringRef, bool>> &SymbolNames) {744 745  JITDylib *JD = nullptr;746 747  {748    std::lock_guard<std::mutex> Lock(PlatformMutex);749    auto I = HeaderAddrToJITDylib.find(Handle);750    if (I != HeaderAddrToJITDylib.end())751      JD = I->second;752  }753  LLVM_DEBUG({754    dbgs() << "MachOPlatform::rt_pushSymbols(";755    if (JD)756      dbgs() << "\"" << JD->getName() << "\", [ ";757    else758      dbgs() << "<invalid handle " << Handle << ">, [ ";759    for (auto &Name : SymbolNames)760      dbgs() << "\"" << Name.first << "\" ";761    dbgs() << "])\n";762  });763 764  if (!JD) {765    SendResult(make_error<StringError>("No JITDylib associated with handle " +766                                           formatv("{0:x}", Handle),767                                       inconvertibleErrorCode()));768    return;769  }770 771  SymbolLookupSet LS;772  for (auto &[Name, Required] : SymbolNames)773    LS.add(ES.intern(Name), Required774                                ? SymbolLookupFlags::RequiredSymbol775                                : SymbolLookupFlags::WeaklyReferencedSymbol);776 777  ES.lookup(778      LookupKind::DLSym, {{JD, JITDylibLookupFlags::MatchExportedSymbolsOnly}},779      std::move(LS), SymbolState::Ready,780      [SendResult = std::move(SendResult)](Expected<SymbolMap> Result) mutable {781        SendResult(Result.takeError());782      },783      NoDependenciesToRegister);784}785 786Expected<uint64_t> MachOPlatform::createPThreadKey() {787  if (!CreatePThreadKey.Addr)788    return make_error<StringError>(789        "Attempting to create pthread key in target, but runtime support has "790        "not been loaded yet",791        inconvertibleErrorCode());792 793  Expected<uint64_t> Result(0);794  if (auto Err = ES.callSPSWrapper<SPSExpected<uint64_t>(void)>(795          CreatePThreadKey.Addr, Result))796    return std::move(Err);797  return Result;798}799 800void MachOPlatform::MachOPlatformPlugin::modifyPassConfig(801    MaterializationResponsibility &MR, jitlink::LinkGraph &LG,802    jitlink::PassConfiguration &Config) {803 804  using namespace jitlink;805 806  bool InBootstrapPhase = false;807 808  ExecutorAddr HeaderAddr;809  {810    std::lock_guard<std::mutex> Lock(MP.PlatformMutex);811    if (LLVM_UNLIKELY(&MR.getTargetJITDylib() == &MP.PlatformJD)) {812      if (MP.Bootstrap) {813        InBootstrapPhase = true;814        ++MP.Bootstrap->ActiveGraphs;815      }816    }817 818    // Get the dso-base address if available.819    auto I = MP.JITDylibToHeaderAddr.find(&MR.getTargetJITDylib());820    if (I != MP.JITDylibToHeaderAddr.end())821      HeaderAddr = I->second;822  }823 824  // If we're forcing eh-frame use then discard the compact-unwind section825  // immediately to prevent FDEs from being stripped.826  if (MP.ForceEHFrames)827    if (auto *CUSec = LG.findSectionByName(MachOCompactUnwindSectionName))828      LG.removeSection(*CUSec);829 830  // Point the libunwind dso-base absolute symbol at the header for the831  // JITDylib. This will prevent us from synthesizing a new header for832  // every object.833  if (HeaderAddr)834    LG.addAbsoluteSymbol("__jitlink$libunwind_dso_base", HeaderAddr, 0,835                         Linkage::Strong, Scope::Local, true);836 837  // If we're in the bootstrap phase then increment the active graphs.838  if (LLVM_UNLIKELY(InBootstrapPhase))839    Config.PostAllocationPasses.push_back([this](LinkGraph &G) {840      return bootstrapPipelineRecordRuntimeFunctions(G);841    });842 843  // --- Handle Initializers ---844  if (auto InitSymbol = MR.getInitializerSymbol()) {845 846    // If the initializer symbol is the MachOHeader start symbol then just847    // register it and then bail out -- the header materialization unit848    // definitely doesn't need any other passes.849    if (InitSymbol == MP.MachOHeaderStartSymbol && !InBootstrapPhase) {850      Config.PostAllocationPasses.push_back([this, &MR](LinkGraph &G) {851        return associateJITDylibHeaderSymbol(G, MR);852      });853      return;854    }855 856    // If the object contains an init symbol other than the header start symbol857    // then add passes to preserve, process and register the init858    // sections/symbols.859    Config.PrePrunePasses.push_back([this, &MR](LinkGraph &G) {860      if (auto Err = preserveImportantSections(G, MR))861        return Err;862      return processObjCImageInfo(G, MR);863    });864    Config.PostPrunePasses.push_back(865        [this](LinkGraph &G) { return createObjCRuntimeObject(G); });866    Config.PostAllocationPasses.push_back(867        [this, &MR](LinkGraph &G) { return populateObjCRuntimeObject(G, MR); });868  }869 870  // Insert TLV lowering at the start of the PostPrunePasses, since we want871  // it to run before GOT/PLT lowering.872  Config.PostPrunePasses.insert(873      Config.PostPrunePasses.begin(),874      [this, &JD = MR.getTargetJITDylib()](LinkGraph &G) {875        return fixTLVSectionsAndEdges(G, JD);876      });877 878  // Add symbol table prepare and register passes: These will add strings for879  // all symbols to the c-strings section, and build a symbol table registration880  // call.881  auto JITSymTabInfo = std::make_shared<JITSymTabVector>();882  Config.PostPrunePasses.push_back([this, JITSymTabInfo](LinkGraph &G) {883    return prepareSymbolTableRegistration(G, *JITSymTabInfo);884  });885  Config.PostFixupPasses.push_back([this, &MR, JITSymTabInfo,886                                    InBootstrapPhase](LinkGraph &G) {887    return addSymbolTableRegistration(G, MR, *JITSymTabInfo, InBootstrapPhase);888  });889 890  // Add a pass to register the final addresses of any special sections in the891  // object with the runtime.892  Config.PostAllocationPasses.push_back([this, &JD = MR.getTargetJITDylib(),893                                         HeaderAddr,894                                         InBootstrapPhase](LinkGraph &G) {895    return registerObjectPlatformSections(G, JD, HeaderAddr, InBootstrapPhase);896  });897 898  // If we're in the bootstrap phase then steal allocation actions and then899  // decrement the active graphs.900  if (InBootstrapPhase)901    Config.PostFixupPasses.push_back(902        [this](LinkGraph &G) { return bootstrapPipelineEnd(G); });903}904 905Error MachOPlatform::MachOPlatformPlugin::906    bootstrapPipelineRecordRuntimeFunctions(jitlink::LinkGraph &G) {907  // Record bootstrap function names.908  std::pair<StringRef, ExecutorAddr *> RuntimeSymbols[] = {909      {*MP.MachOHeaderStartSymbol, &MP.Bootstrap->MachOHeaderAddr},910      {*MP.PlatformBootstrap.Name, &MP.PlatformBootstrap.Addr},911      {*MP.PlatformShutdown.Name, &MP.PlatformShutdown.Addr},912      {*MP.RegisterJITDylib.Name, &MP.RegisterJITDylib.Addr},913      {*MP.DeregisterJITDylib.Name, &MP.DeregisterJITDylib.Addr},914      {*MP.RegisterObjectSymbolTable.Name, &MP.RegisterObjectSymbolTable.Addr},915      {*MP.DeregisterObjectSymbolTable.Name,916       &MP.DeregisterObjectSymbolTable.Addr},917      {*MP.RegisterObjectPlatformSections.Name,918       &MP.RegisterObjectPlatformSections.Addr},919      {*MP.DeregisterObjectPlatformSections.Name,920       &MP.DeregisterObjectPlatformSections.Addr},921      {*MP.CreatePThreadKey.Name, &MP.CreatePThreadKey.Addr},922      {*MP.RegisterObjCRuntimeObject.Name, &MP.RegisterObjCRuntimeObject.Addr},923      {*MP.DeregisterObjCRuntimeObject.Name,924       &MP.DeregisterObjCRuntimeObject.Addr}};925 926  bool RegisterMachOHeader = false;927 928  for (auto *Sym : G.defined_symbols()) {929    for (auto &RTSym : RuntimeSymbols) {930      if (Sym->hasName() && *Sym->getName() == RTSym.first) {931        if (*RTSym.second)932          return make_error<StringError>(933              "Duplicate " + RTSym.first +934                  " detected during MachOPlatform bootstrap",935              inconvertibleErrorCode());936 937        if (Sym->getName() == MP.MachOHeaderStartSymbol)938          RegisterMachOHeader = true;939 940        *RTSym.second = Sym->getAddress();941      }942    }943  }944 945  if (RegisterMachOHeader) {946    // If this graph defines the macho header symbol then create the internal947    // mapping between it and PlatformJD.948    std::lock_guard<std::mutex> Lock(MP.PlatformMutex);949    MP.JITDylibToHeaderAddr[&MP.PlatformJD] = MP.Bootstrap->MachOHeaderAddr;950    MP.HeaderAddrToJITDylib[MP.Bootstrap->MachOHeaderAddr] = &MP.PlatformJD;951  }952 953  return Error::success();954}955 956Error MachOPlatform::MachOPlatformPlugin::bootstrapPipelineEnd(957    jitlink::LinkGraph &G) {958  std::lock_guard<std::mutex> Lock(MP.PlatformMutex);959 960  --MP.Bootstrap->ActiveGraphs;961  // Notify Bootstrap->CV while holding the mutex because the mutex is962  // also keeping Bootstrap->CV alive.963  if (MP.Bootstrap->ActiveGraphs == 0)964    MP.Bootstrap->CV.notify_all();965  return Error::success();966}967 968Error MachOPlatform::MachOPlatformPlugin::associateJITDylibHeaderSymbol(969    jitlink::LinkGraph &G, MaterializationResponsibility &MR) {970  auto I = llvm::find_if(G.defined_symbols(), [this](jitlink::Symbol *Sym) {971    return Sym->getName() == MP.MachOHeaderStartSymbol;972  });973  assert(I != G.defined_symbols().end() && "Missing MachO header start symbol");974 975  auto &JD = MR.getTargetJITDylib();976  std::lock_guard<std::mutex> Lock(MP.PlatformMutex);977  auto HeaderAddr = (*I)->getAddress();978  MP.JITDylibToHeaderAddr[&JD] = HeaderAddr;979  MP.HeaderAddrToJITDylib[HeaderAddr] = &JD;980  // We can unconditionally add these actions to the Graph because this pass981  // isn't used during bootstrap.982  G.allocActions().push_back(983      {cantFail(984           WrapperFunctionCall::Create<SPSArgList<SPSString, SPSExecutorAddr>>(985               MP.RegisterJITDylib.Addr, JD.getName(), HeaderAddr)),986       cantFail(WrapperFunctionCall::Create<SPSArgList<SPSExecutorAddr>>(987           MP.DeregisterJITDylib.Addr, HeaderAddr))});988  return Error::success();989}990 991Error MachOPlatform::MachOPlatformPlugin::preserveImportantSections(992    jitlink::LinkGraph &G, MaterializationResponsibility &MR) {993  // __objc_imageinfo is "important": we want to preserve it and record its994  // address in the first graph that it appears in, then verify and discard it995  // in all subsequent graphs. In this pass we preserve unconditionally -- we'll996  // manually throw it away in the processObjCImageInfo pass.997  if (auto *ObjCImageInfoSec =998          G.findSectionByName(MachOObjCImageInfoSectionName)) {999    if (ObjCImageInfoSec->blocks_size() != 1)1000      return make_error<StringError>(1001          "In " + G.getName() +1002              "__DATA,__objc_imageinfo contains multiple blocks",1003          inconvertibleErrorCode());1004    G.addAnonymousSymbol(**ObjCImageInfoSec->blocks().begin(), 0, 0, false,1005                         true);1006 1007    for (auto *B : ObjCImageInfoSec->blocks())1008      if (!B->edges_empty())1009        return make_error<StringError>("In " + G.getName() + ", " +1010                                           MachOObjCImageInfoSectionName +1011                                           " contains references to symbols",1012                                       inconvertibleErrorCode());1013  }1014 1015  // Init sections are important: We need to preserve them and so that their1016  // addresses can be captured and reported to the ORC runtime in1017  // registerObjectPlatformSections.1018  if (const auto &InitSymName = MR.getInitializerSymbol()) {1019 1020    jitlink::Symbol *InitSym = nullptr;1021    for (auto &InitSectionName : MachOInitSectionNames) {1022      // Skip ObjCImageInfo -- this shouldn't have any dependencies, and we may1023      // remove it later.1024      if (InitSectionName == MachOObjCImageInfoSectionName)1025        continue;1026 1027      // Skip non-init sections.1028      auto *InitSection = G.findSectionByName(InitSectionName);1029      if (!InitSection || InitSection->empty())1030        continue;1031 1032      // Create the init symbol if it has not been created already and attach it1033      // to the first block.1034      if (!InitSym) {1035        auto &B = **InitSection->blocks().begin();1036        InitSym = &G.addDefinedSymbol(1037            B, 0, *InitSymName, B.getSize(), jitlink::Linkage::Strong,1038            jitlink::Scope::SideEffectsOnly, false, true);1039      }1040 1041      // Add keep-alive edges to anonymous symbols in all other init blocks.1042      for (auto *B : InitSection->blocks()) {1043        if (B == &InitSym->getBlock())1044          continue;1045 1046        auto &S = G.addAnonymousSymbol(*B, 0, B->getSize(), false, true);1047        InitSym->getBlock().addEdge(jitlink::Edge::KeepAlive, 0, S, 0);1048      }1049    }1050  }1051 1052  return Error::success();1053}1054 1055Error MachOPlatform::MachOPlatformPlugin::processObjCImageInfo(1056    jitlink::LinkGraph &G, MaterializationResponsibility &MR) {1057 1058  // If there's an ObjC imagine info then either1059  //   (1) It's the first __objc_imageinfo we've seen in this JITDylib. In1060  //       this case we name and record it.1061  // OR1062  //   (2) We already have a recorded __objc_imageinfo for this JITDylib,1063  //       in which case we just verify it.1064  auto *ObjCImageInfo = G.findSectionByName(MachOObjCImageInfoSectionName);1065  if (!ObjCImageInfo)1066    return Error::success();1067 1068  auto ObjCImageInfoBlocks = ObjCImageInfo->blocks();1069 1070  // Check that the section is not empty if present.1071  if (ObjCImageInfoBlocks.empty())1072    return make_error<StringError>("Empty " + MachOObjCImageInfoSectionName +1073                                       " section in " + G.getName(),1074                                   inconvertibleErrorCode());1075 1076  // Check that there's only one block in the section.1077  if (std::next(ObjCImageInfoBlocks.begin()) != ObjCImageInfoBlocks.end())1078    return make_error<StringError>("Multiple blocks in " +1079                                       MachOObjCImageInfoSectionName +1080                                       " section in " + G.getName(),1081                                   inconvertibleErrorCode());1082 1083  // Check that the __objc_imageinfo section is unreferenced.1084  // FIXME: We could optimize this check if Symbols had a ref-count.1085  for (auto &Sec : G.sections()) {1086    if (&Sec != ObjCImageInfo)1087      for (auto *B : Sec.blocks())1088        for (auto &E : B->edges())1089          if (E.getTarget().isDefined() &&1090              &E.getTarget().getSection() == ObjCImageInfo)1091            return make_error<StringError>(MachOObjCImageInfoSectionName +1092                                               " is referenced within file " +1093                                               G.getName(),1094                                           inconvertibleErrorCode());1095  }1096 1097  auto &ObjCImageInfoBlock = **ObjCImageInfoBlocks.begin();1098  auto *ObjCImageInfoData = ObjCImageInfoBlock.getContent().data();1099  auto Version = support::endian::read32(ObjCImageInfoData, G.getEndianness());1100  auto Flags =1101      support::endian::read32(ObjCImageInfoData + 4, G.getEndianness());1102 1103  // Lock the mutex while we verify / update the ObjCImageInfos map.1104  std::lock_guard<std::mutex> Lock(PluginMutex);1105 1106  auto ObjCImageInfoItr = ObjCImageInfos.find(&MR.getTargetJITDylib());1107  if (ObjCImageInfoItr != ObjCImageInfos.end()) {1108    // We've already registered an __objc_imageinfo section. Verify the1109    // content of this new section matches, then delete it.1110    if (ObjCImageInfoItr->second.Version != Version)1111      return make_error<StringError>(1112          "ObjC version in " + G.getName() +1113              " does not match first registered version",1114          inconvertibleErrorCode());1115    if (ObjCImageInfoItr->second.Flags != Flags)1116      if (Error E = mergeImageInfoFlags(G, MR, ObjCImageInfoItr->second, Flags))1117        return E;1118 1119    // __objc_imageinfo is valid. Delete the block.1120    for (auto *S : ObjCImageInfo->symbols())1121      G.removeDefinedSymbol(*S);1122    G.removeBlock(ObjCImageInfoBlock);1123  } else {1124    LLVM_DEBUG({1125      dbgs() << "MachOPlatform: Registered __objc_imageinfo for "1126             << MR.getTargetJITDylib().getName() << " in " << G.getName()1127             << "; flags = " << formatv("{0:x4}", Flags) << "\n";1128    });1129    // We haven't registered an __objc_imageinfo section yet. Register and1130    // move on. The section should already be marked no-dead-strip.1131    G.addDefinedSymbol(ObjCImageInfoBlock, 0, ObjCImageInfoSymbolName,1132                       ObjCImageInfoBlock.getSize(), jitlink::Linkage::Strong,1133                       jitlink::Scope::Hidden, false, true);1134    if (auto Err = MR.defineMaterializing(1135            {{MR.getExecutionSession().intern(ObjCImageInfoSymbolName),1136              JITSymbolFlags()}}))1137      return Err;1138    ObjCImageInfos[&MR.getTargetJITDylib()] = {Version, Flags, false};1139  }1140 1141  return Error::success();1142}1143 1144Error MachOPlatform::MachOPlatformPlugin::mergeImageInfoFlags(1145    jitlink::LinkGraph &G, MaterializationResponsibility &MR,1146    ObjCImageInfo &Info, uint32_t NewFlags) {1147  if (Info.Flags == NewFlags)1148    return Error::success();1149 1150  ObjCImageInfoFlags Old(Info.Flags);1151  ObjCImageInfoFlags New(NewFlags);1152 1153  // Check for incompatible flags.1154  if (Old.SwiftABIVersion && New.SwiftABIVersion &&1155      Old.SwiftABIVersion != New.SwiftABIVersion)1156    return make_error<StringError>("Swift ABI version in " + G.getName() +1157                                       " does not match first registered flags",1158                                   inconvertibleErrorCode());1159 1160  // HasCategoryClassProperties and HasSignedObjCClassROs can be disabled before1161  // they are registered, if necessary, but once they are in use must be1162  // supported by subsequent objects.1163  if (Info.Finalized && Old.HasCategoryClassProperties &&1164      !New.HasCategoryClassProperties)1165    return make_error<StringError>("ObjC category class property support in " +1166                                       G.getName() +1167                                       " does not match first registered flags",1168                                   inconvertibleErrorCode());1169  if (Info.Finalized && Old.HasSignedObjCClassROs && !New.HasSignedObjCClassROs)1170    return make_error<StringError>("ObjC class_ro_t pointer signing in " +1171                                       G.getName() +1172                                       " does not match first registered flags",1173                                   inconvertibleErrorCode());1174 1175  // If we cannot change the flags, ignore any remaining differences. Adding1176  // Swift or changing its version are unlikely to cause problems in practice.1177  if (Info.Finalized)1178    return Error::success();1179 1180  // Use the minimum Swift version.1181  if (Old.SwiftVersion && New.SwiftVersion)1182    New.SwiftVersion = std::min(Old.SwiftVersion, New.SwiftVersion);1183  else if (Old.SwiftVersion)1184    New.SwiftVersion = Old.SwiftVersion;1185  // Add a Swift ABI version if it was pure objc before.1186  if (!New.SwiftABIVersion)1187    New.SwiftABIVersion = Old.SwiftABIVersion;1188  // Disable class properties if any object does not support it.1189  if (Old.HasCategoryClassProperties != New.HasCategoryClassProperties)1190    New.HasCategoryClassProperties = false;1191  // Disable signed class ro data if any object does not support it.1192  if (Old.HasSignedObjCClassROs != New.HasSignedObjCClassROs)1193    New.HasSignedObjCClassROs = false;1194 1195  LLVM_DEBUG({1196    dbgs() << "MachOPlatform: Merging __objc_imageinfo flags for "1197           << MR.getTargetJITDylib().getName() << " (was "1198           << formatv("{0:x4}", Old.rawFlags()) << ")"1199           << " with " << G.getName() << " (" << formatv("{0:x4}", NewFlags)1200           << ")"1201           << " -> " << formatv("{0:x4}", New.rawFlags()) << "\n";1202  });1203 1204  Info.Flags = New.rawFlags();1205  return Error::success();1206}1207 1208Error MachOPlatform::MachOPlatformPlugin::fixTLVSectionsAndEdges(1209    jitlink::LinkGraph &G, JITDylib &JD) {1210  auto TLVBootStrapSymbolName = G.intern("__tlv_bootstrap");1211  // Rename external references to __tlv_bootstrap to ___orc_rt_tlv_get_addr.1212  for (auto *Sym : G.external_symbols())1213    if (Sym->getName() == TLVBootStrapSymbolName) {1214      auto TLSGetADDR =1215          MP.getExecutionSession().intern("___orc_rt_macho_tlv_get_addr");1216      Sym->setName(std::move(TLSGetADDR));1217      break;1218    }1219 1220  // Store key in __thread_vars struct fields.1221  if (auto *ThreadDataSec = G.findSectionByName(MachOThreadVarsSectionName)) {1222    std::optional<uint64_t> Key;1223    {1224      std::lock_guard<std::mutex> Lock(MP.PlatformMutex);1225      auto I = MP.JITDylibToPThreadKey.find(&JD);1226      if (I != MP.JITDylibToPThreadKey.end())1227        Key = I->second;1228    }1229 1230    if (!Key) {1231      if (auto KeyOrErr = MP.createPThreadKey())1232        Key = *KeyOrErr;1233      else1234        return KeyOrErr.takeError();1235    }1236 1237    uint64_t PlatformKeyBits =1238        support::endian::byte_swap(*Key, G.getEndianness());1239 1240    for (auto *B : ThreadDataSec->blocks()) {1241      if (B->getSize() != 3 * G.getPointerSize())1242        return make_error<StringError>("__thread_vars block at " +1243                                           formatv("{0:x}", B->getAddress()) +1244                                           " has unexpected size",1245                                       inconvertibleErrorCode());1246 1247      auto NewBlockContent = G.allocateBuffer(B->getSize());1248      llvm::copy(B->getContent(), NewBlockContent.data());1249      memcpy(NewBlockContent.data() + G.getPointerSize(), &PlatformKeyBits,1250             G.getPointerSize());1251      B->setContent(NewBlockContent);1252    }1253  }1254 1255  // Transform any TLV edges into GOT edges.1256  for (auto *B : G.blocks())1257    for (auto &E : B->edges())1258      if (E.getKind() ==1259          jitlink::x86_64::RequestTLVPAndTransformToPCRel32TLVPLoadREXRelaxable)1260        E.setKind(jitlink::x86_64::1261                      RequestGOTAndTransformToPCRel32GOTLoadREXRelaxable);1262 1263  return Error::success();1264}1265 1266std::optional<MachOPlatform::MachOPlatformPlugin::UnwindSections>1267MachOPlatform::MachOPlatformPlugin::findUnwindSectionInfo(1268    jitlink::LinkGraph &G) {1269  using namespace jitlink;1270 1271  UnwindSections US;1272 1273  // ScanSection records a section range and adds any executable blocks that1274  // that section points to to the CodeBlocks vector.1275  SmallVector<Block *> CodeBlocks;1276  auto ScanUnwindInfoSection = [&](Section &Sec, ExecutorAddrRange &SecRange,1277                                   auto AddCodeBlocks) {1278    if (Sec.blocks().empty())1279      return;1280    SecRange = (*Sec.blocks().begin())->getRange();1281    for (auto *B : Sec.blocks()) {1282      auto R = B->getRange();1283      SecRange.Start = std::min(SecRange.Start, R.Start);1284      SecRange.End = std::max(SecRange.End, R.End);1285      AddCodeBlocks(*B);1286    }1287  };1288 1289  if (Section *EHFrameSec = G.findSectionByName(MachOEHFrameSectionName)) {1290    ScanUnwindInfoSection(*EHFrameSec, US.DwarfSection, [&](Block &B) {1291      if (auto *Fn = jitlink::EHFrameCFIBlockInspector::FromEdgeScan(B)1292                         .getPCBeginEdge())1293        if (Fn->getTarget().isDefined())1294          CodeBlocks.push_back(&Fn->getTarget().getBlock());1295    });1296  }1297 1298  if (Section *CUInfoSec = G.findSectionByName(MachOUnwindInfoSectionName)) {1299    ScanUnwindInfoSection(1300        *CUInfoSec, US.CompactUnwindSection, [&](Block &B) {1301          for (auto &E : B.edges()) {1302            assert(E.getTarget().isDefined() &&1303                   "unwind-info record edge has external target");1304            assert(E.getKind() == Edge::KeepAlive &&1305                   "unwind-info record has unexpected edge kind");1306            CodeBlocks.push_back(&E.getTarget().getBlock());1307          }1308        });1309  }1310 1311  // If we didn't find any pointed-to code-blocks then there's no need to1312  // register any info.1313  if (CodeBlocks.empty())1314    return std::nullopt;1315 1316  // We have info to register. Sort the code blocks into address order and1317  // build a list of contiguous address ranges covering them all.1318  llvm::sort(CodeBlocks, [](const Block *LHS, const Block *RHS) {1319    return LHS->getAddress() < RHS->getAddress();1320  });1321  for (auto *B : CodeBlocks) {1322    if (US.CodeRanges.empty() || US.CodeRanges.back().End != B->getAddress())1323      US.CodeRanges.push_back(B->getRange());1324    else1325      US.CodeRanges.back().End = B->getRange().End;1326  }1327 1328  LLVM_DEBUG({1329    dbgs() << "MachOPlatform identified unwind info in " << G.getName() << ":\n"1330           << "  DWARF: ";1331    if (US.DwarfSection.Start)1332      dbgs() << US.DwarfSection << "\n";1333    else1334      dbgs() << "none\n";1335    dbgs() << "  Compact-unwind: ";1336    if (US.CompactUnwindSection.Start)1337      dbgs() << US.CompactUnwindSection << "\n";1338    else1339      dbgs() << "none\n"1340             << "for code ranges:\n";1341    for (auto &CR : US.CodeRanges)1342      dbgs() << "  " << CR << "\n";1343    if (US.CodeRanges.size() >= G.sections_size())1344      dbgs() << "WARNING: High number of discontiguous code ranges! "1345                "Padding may be interfering with coalescing.\n";1346  });1347 1348  return US;1349}1350 1351Error MachOPlatform::MachOPlatformPlugin::registerObjectPlatformSections(1352    jitlink::LinkGraph &G, JITDylib &JD, ExecutorAddr HeaderAddr,1353    bool InBootstrapPhase) {1354 1355  // Get a pointer to the thread data section if there is one. It will be used1356  // below.1357  jitlink::Section *ThreadDataSection =1358      G.findSectionByName(MachOThreadDataSectionName);1359 1360  // Handle thread BSS section if there is one.1361  if (auto *ThreadBSSSection = G.findSectionByName(MachOThreadBSSSectionName)) {1362    // If there's already a thread data section in this graph then merge the1363    // thread BSS section content into it, otherwise just treat the thread1364    // BSS section as the thread data section.1365    if (ThreadDataSection)1366      G.mergeSections(*ThreadDataSection, *ThreadBSSSection);1367    else1368      ThreadDataSection = ThreadBSSSection;1369  }1370 1371  SmallVector<std::pair<StringRef, ExecutorAddrRange>, 8> MachOPlatformSecs;1372 1373  // Collect data sections to register.1374  StringRef DataSections[] = {MachODataDataSectionName,1375                              MachODataCommonSectionName,1376                              MachOEHFrameSectionName};1377  for (auto &SecName : DataSections) {1378    if (auto *Sec = G.findSectionByName(SecName)) {1379      jitlink::SectionRange R(*Sec);1380      if (!R.empty())1381        MachOPlatformSecs.push_back({SecName, R.getRange()});1382    }1383  }1384 1385  // Having merged thread BSS (if present) and thread data (if present),1386  // record the resulting section range.1387  if (ThreadDataSection) {1388    jitlink::SectionRange R(*ThreadDataSection);1389    if (!R.empty())1390      MachOPlatformSecs.push_back({MachOThreadDataSectionName, R.getRange()});1391  }1392 1393  // If any platform sections were found then add an allocation action to call1394  // the registration function.1395  StringRef PlatformSections[] = {MachOModInitFuncSectionName,1396                                  ObjCRuntimeObjectSectionName};1397 1398  for (auto &SecName : PlatformSections) {1399    auto *Sec = G.findSectionByName(SecName);1400    if (!Sec)1401      continue;1402    jitlink::SectionRange R(*Sec);1403    if (R.empty())1404      continue;1405 1406    MachOPlatformSecs.push_back({SecName, R.getRange()});1407  }1408 1409  std::optional<std::tuple<SmallVector<ExecutorAddrRange>, ExecutorAddrRange,1410                           ExecutorAddrRange>>1411      UnwindInfo;1412  if (auto UI = findUnwindSectionInfo(G))1413    UnwindInfo = std::make_tuple(std::move(UI->CodeRanges), UI->DwarfSection,1414                                 UI->CompactUnwindSection);1415 1416  if (!MachOPlatformSecs.empty() || UnwindInfo) {1417    // Dump the scraped inits.1418    LLVM_DEBUG({1419      dbgs() << "MachOPlatform: Scraped " << G.getName() << " init sections:\n";1420      for (auto &KV : MachOPlatformSecs)1421        dbgs() << "  " << KV.first << ": " << KV.second << "\n";1422    });1423 1424    assert(HeaderAddr && "Null header registered for JD");1425    using SPSRegisterObjectPlatformSectionsArgs = SPSArgList<1426        SPSExecutorAddr,1427        SPSOptional<SPSTuple<SPSSequence<SPSExecutorAddrRange>,1428                             SPSExecutorAddrRange, SPSExecutorAddrRange>>,1429        SPSSequence<SPSTuple<SPSString, SPSExecutorAddrRange>>>;1430 1431    AllocActionCallPair AllocActions = {1432        cantFail(1433            WrapperFunctionCall::Create<SPSRegisterObjectPlatformSectionsArgs>(1434                MP.RegisterObjectPlatformSections.Addr, HeaderAddr, UnwindInfo,1435                MachOPlatformSecs)),1436        cantFail(1437            WrapperFunctionCall::Create<SPSRegisterObjectPlatformSectionsArgs>(1438                MP.DeregisterObjectPlatformSections.Addr, HeaderAddr,1439                UnwindInfo, MachOPlatformSecs))};1440 1441    if (LLVM_LIKELY(!InBootstrapPhase))1442      G.allocActions().push_back(std::move(AllocActions));1443    else {1444      std::lock_guard<std::mutex> Lock(MP.PlatformMutex);1445      MP.Bootstrap->DeferredAAs.push_back(std::move(AllocActions));1446    }1447  }1448 1449  return Error::success();1450}1451 1452Error MachOPlatform::MachOPlatformPlugin::createObjCRuntimeObject(1453    jitlink::LinkGraph &G) {1454 1455  bool NeedTextSegment = false;1456  size_t NumRuntimeSections = 0;1457 1458  for (auto ObjCRuntimeSectionName : ObjCRuntimeObjectSectionsData)1459    if (G.findSectionByName(ObjCRuntimeSectionName))1460      ++NumRuntimeSections;1461 1462  for (auto ObjCRuntimeSectionName : ObjCRuntimeObjectSectionsText) {1463    if (G.findSectionByName(ObjCRuntimeSectionName)) {1464      ++NumRuntimeSections;1465      NeedTextSegment = true;1466    }1467  }1468 1469  // Early out for no runtime sections.1470  if (NumRuntimeSections == 0)1471    return Error::success();1472 1473  // If there were any runtime sections then we need to add an __objc_imageinfo1474  // section.1475  ++NumRuntimeSections;1476 1477  size_t MachOSize = sizeof(MachO::mach_header_64) +1478                     (NeedTextSegment + 1) * sizeof(MachO::segment_command_64) +1479                     NumRuntimeSections * sizeof(MachO::section_64);1480 1481  auto &Sec = G.createSection(ObjCRuntimeObjectSectionName,1482                              MemProt::Read | MemProt::Write);1483  G.createMutableContentBlock(Sec, MachOSize, ExecutorAddr(), 16, 0, true);1484 1485  return Error::success();1486}1487 1488Error MachOPlatform::MachOPlatformPlugin::populateObjCRuntimeObject(1489    jitlink::LinkGraph &G, MaterializationResponsibility &MR) {1490 1491  auto *ObjCRuntimeObjectSec =1492      G.findSectionByName(ObjCRuntimeObjectSectionName);1493 1494  if (!ObjCRuntimeObjectSec)1495    return Error::success();1496 1497  switch (G.getTargetTriple().getArch()) {1498  case Triple::aarch64:1499  case Triple::x86_64:1500    // Supported.1501    break;1502  default:1503    return make_error<StringError>("Unrecognized MachO arch in triple " +1504                                       G.getTargetTriple().str(),1505                                   inconvertibleErrorCode());1506  }1507 1508  auto &SecBlock = **ObjCRuntimeObjectSec->blocks().begin();1509 1510  struct SecDesc {1511    MachO::section_64 Sec;1512    unique_function<void(size_t RecordOffset)> AddFixups;1513  };1514 1515  std::vector<SecDesc> TextSections, DataSections;1516  auto AddSection = [&](SecDesc &SD, jitlink::Section &GraphSec) {1517    jitlink::SectionRange SR(GraphSec);1518    StringRef FQName = GraphSec.getName();1519    memset(&SD.Sec, 0, sizeof(MachO::section_64));1520    memcpy(SD.Sec.sectname, FQName.drop_front(7).data(), FQName.size() - 7);1521    memcpy(SD.Sec.segname, FQName.data(), 6);1522    SD.Sec.addr = SR.getStart() - SecBlock.getAddress();1523    SD.Sec.size = SR.getSize();1524    SD.Sec.flags = MachO::S_REGULAR;1525  };1526 1527  // Add the __objc_imageinfo section.1528  {1529    DataSections.push_back({});1530    auto &SD = DataSections.back();1531    memset(&SD.Sec, 0, sizeof(SD.Sec));1532    memcpy(SD.Sec.sectname, "__objc_imageinfo", 16);1533    strcpy(SD.Sec.segname, "__DATA");1534    SD.Sec.size = 8;1535    jitlink::Symbol *ObjCImageInfoSym = nullptr;1536    SD.AddFixups = [&, ObjCImageInfoSym](size_t RecordOffset) mutable {1537      auto PointerEdge = getPointerEdgeKind(G);1538 1539      // Look for an existing __objc_imageinfo symbol.1540      if (!ObjCImageInfoSym) {1541        auto Name = G.intern(ObjCImageInfoSymbolName);1542        ObjCImageInfoSym = G.findExternalSymbolByName(Name);1543        if (!ObjCImageInfoSym)1544          ObjCImageInfoSym = G.findAbsoluteSymbolByName(Name);1545        if (!ObjCImageInfoSym) {1546          ObjCImageInfoSym = G.findDefinedSymbolByName(Name);1547          if (ObjCImageInfoSym) {1548            std::optional<uint32_t> Flags;1549            {1550              std::lock_guard<std::mutex> Lock(PluginMutex);1551              auto It = ObjCImageInfos.find(&MR.getTargetJITDylib());1552              if (It != ObjCImageInfos.end()) {1553                It->second.Finalized = true;1554                Flags = It->second.Flags;1555              }1556            }1557 1558            if (Flags) {1559              // We own the definition of __objc_image_info; write the final1560              // merged flags value.1561              auto Content = ObjCImageInfoSym->getBlock().getMutableContent(G);1562              assert(1563                  Content.size() == 8 &&1564                  "__objc_image_info size should have been verified already");1565              support::endian::write32(&Content[4], *Flags, G.getEndianness());1566            }1567          }1568        }1569        if (!ObjCImageInfoSym)1570          ObjCImageInfoSym = &G.addExternalSymbol(std::move(Name), 8, false);1571      }1572 1573      SecBlock.addEdge(PointerEdge,1574                       RecordOffset + ((char *)&SD.Sec.addr - (char *)&SD.Sec),1575                       *ObjCImageInfoSym, -SecBlock.getAddress().getValue());1576    };1577  }1578 1579  for (auto ObjCRuntimeSectionName : ObjCRuntimeObjectSectionsData) {1580    if (auto *GraphSec = G.findSectionByName(ObjCRuntimeSectionName)) {1581      DataSections.push_back({});1582      AddSection(DataSections.back(), *GraphSec);1583    }1584  }1585 1586  for (auto ObjCRuntimeSectionName : ObjCRuntimeObjectSectionsText) {1587    if (auto *GraphSec = G.findSectionByName(ObjCRuntimeSectionName)) {1588      TextSections.push_back({});1589      AddSection(TextSections.back(), *GraphSec);1590    }1591  }1592 1593  assert(ObjCRuntimeObjectSec->blocks_size() == 1 &&1594         "Unexpected number of blocks in runtime sections object");1595 1596  // Build the header struct up-front. This also gives us a chance to check1597  // that the triple is supported, which we'll assume below.1598  MachO::mach_header_64 Hdr;1599  Hdr.magic = MachO::MH_MAGIC_64;1600  switch (G.getTargetTriple().getArch()) {1601  case Triple::aarch64:1602    Hdr.cputype = MachO::CPU_TYPE_ARM64;1603    Hdr.cpusubtype = MachO::CPU_SUBTYPE_ARM64_ALL;1604    break;1605  case Triple::x86_64:1606    Hdr.cputype = MachO::CPU_TYPE_X86_64;1607    Hdr.cpusubtype = MachO::CPU_SUBTYPE_X86_64_ALL;1608    break;1609  default:1610    llvm_unreachable("Unsupported architecture");1611  }1612 1613  Hdr.filetype = MachO::MH_DYLIB;1614  Hdr.ncmds = 1 + !TextSections.empty();1615  Hdr.sizeofcmds =1616      Hdr.ncmds * sizeof(MachO::segment_command_64) +1617      (TextSections.size() + DataSections.size()) * sizeof(MachO::section_64);1618  Hdr.flags = 0;1619  Hdr.reserved = 0;1620 1621  auto SecContent = SecBlock.getAlreadyMutableContent();1622  char *P = SecContent.data();1623  auto WriteMachOStruct = [&](auto S) {1624    if (G.getEndianness() != llvm::endianness::native)1625      MachO::swapStruct(S);1626    memcpy(P, &S, sizeof(S));1627    P += sizeof(S);1628  };1629 1630  auto WriteSegment = [&](StringRef Name, std::vector<SecDesc> &Secs) {1631    MachO::segment_command_64 SegLC;1632    memset(&SegLC, 0, sizeof(SegLC));1633    memcpy(SegLC.segname, Name.data(), Name.size());1634    SegLC.cmd = MachO::LC_SEGMENT_64;1635    SegLC.cmdsize = sizeof(MachO::segment_command_64) +1636                    Secs.size() * sizeof(MachO::section_64);1637    SegLC.nsects = Secs.size();1638    WriteMachOStruct(SegLC);1639    for (auto &SD : Secs) {1640      if (SD.AddFixups)1641        SD.AddFixups(P - SecContent.data());1642      WriteMachOStruct(SD.Sec);1643    }1644  };1645 1646  WriteMachOStruct(Hdr);1647  if (!TextSections.empty())1648    WriteSegment("__TEXT", TextSections);1649  if (!DataSections.empty())1650    WriteSegment("__DATA", DataSections);1651 1652  assert(P == SecContent.end() && "Underflow writing ObjC runtime object");1653  return Error::success();1654}1655 1656Error MachOPlatform::MachOPlatformPlugin::prepareSymbolTableRegistration(1657    jitlink::LinkGraph &G, JITSymTabVector &JITSymTabInfo) {1658 1659  auto *CStringSec = G.findSectionByName(MachOCStringSectionName);1660  if (!CStringSec)1661    CStringSec = &G.createSection(MachOCStringSectionName,1662                                  MemProt::Read | MemProt::Exec);1663 1664  // Make a map of existing strings so that we can re-use them:1665  DenseMap<StringRef, jitlink::Symbol *> ExistingStrings;1666  for (auto *Sym : CStringSec->symbols()) {1667 1668    // The LinkGraph builder should have created single strings blocks, and all1669    // plugins should have maintained this invariant.1670    auto Content = Sym->getBlock().getContent();1671    ExistingStrings.insert(1672        std::make_pair(StringRef(Content.data(), Content.size()), Sym));1673  }1674 1675  // Add all symbol names to the string section, and record the symbols for1676  // those names.1677  {1678    SmallVector<jitlink::Symbol *> SymsToProcess;1679    llvm::append_range(SymsToProcess, G.defined_symbols());1680    llvm::append_range(SymsToProcess, G.absolute_symbols());1681 1682    for (auto *Sym : SymsToProcess) {1683      if (!Sym->hasName())1684        continue;1685 1686      auto I = ExistingStrings.find(*Sym->getName());1687      if (I == ExistingStrings.end()) {1688        auto &NameBlock = G.createMutableContentBlock(1689            *CStringSec, G.allocateCString(*Sym->getName()),1690            orc::ExecutorAddr(), 1, 0);1691        auto &SymbolNameSym = G.addAnonymousSymbol(1692            NameBlock, 0, NameBlock.getSize(), false, true);1693        JITSymTabInfo.push_back({Sym, &SymbolNameSym});1694      } else1695        JITSymTabInfo.push_back({Sym, I->second});1696    }1697  }1698 1699  return Error::success();1700}1701 1702Error MachOPlatform::MachOPlatformPlugin::addSymbolTableRegistration(1703    jitlink::LinkGraph &G, MaterializationResponsibility &MR,1704    JITSymTabVector &JITSymTabInfo, bool InBootstrapPhase) {1705 1706  ExecutorAddr HeaderAddr;1707  {1708    std::lock_guard<std::mutex> Lock(MP.PlatformMutex);1709    auto I = MP.JITDylibToHeaderAddr.find(&MR.getTargetJITDylib());1710    assert(I != MP.JITDylibToHeaderAddr.end() && "No header registered for JD");1711    assert(I->second && "Null header registered for JD");1712    HeaderAddr = I->second;1713  }1714 1715  if (LLVM_UNLIKELY(InBootstrapPhase)) {1716    // If we're in the bootstrap phase then just record these symbols in the1717    // bootstrap object and then bail out -- registration will be attached to1718    // the bootstrap graph.1719    std::lock_guard<std::mutex> Lock(MP.PlatformMutex);1720    auto &SymTab = MP.Bootstrap->SymTab;1721    for (auto &[OriginalSymbol, NameSym] : JITSymTabInfo)1722      SymTab.push_back({NameSym->getAddress(), OriginalSymbol->getAddress(),1723                        flagsForSymbol(*OriginalSymbol)});1724    return Error::success();1725  }1726 1727  SymbolTableVector SymTab;1728  for (auto &[OriginalSymbol, NameSym] : JITSymTabInfo)1729    SymTab.push_back({NameSym->getAddress(), OriginalSymbol->getAddress(),1730                      flagsForSymbol(*OriginalSymbol)});1731 1732  G.allocActions().push_back(1733      {cantFail(WrapperFunctionCall::Create<SPSRegisterSymbolsArgs>(1734           MP.RegisterObjectSymbolTable.Addr, HeaderAddr, SymTab)),1735       cantFail(WrapperFunctionCall::Create<SPSRegisterSymbolsArgs>(1736           MP.DeregisterObjectSymbolTable.Addr, HeaderAddr, SymTab))});1737 1738  return Error::success();1739}1740 1741template <typename MachOTraits>1742jitlink::Block &createHeaderBlock(MachOPlatform &MOP,1743                                  const MachOPlatform::HeaderOptions &Opts,1744                                  JITDylib &JD, jitlink::LinkGraph &G,1745                                  jitlink::Section &HeaderSection) {1746  auto HdrInfo =1747      getMachOHeaderInfoFromTriple(MOP.getExecutionSession().getTargetTriple());1748  MachOBuilder<MachOTraits> B(HdrInfo.PageSize);1749 1750  B.Header.filetype = MachO::MH_DYLIB;1751  B.Header.cputype = HdrInfo.CPUType;1752  B.Header.cpusubtype = HdrInfo.CPUSubType;1753 1754  if (Opts.IDDylib)1755    B.template addLoadCommand<MachO::LC_ID_DYLIB>(1756        Opts.IDDylib->Name, Opts.IDDylib->Timestamp,1757        Opts.IDDylib->CurrentVersion, Opts.IDDylib->CompatibilityVersion);1758  else1759    B.template addLoadCommand<MachO::LC_ID_DYLIB>(JD.getName(), 0, 0, 0);1760 1761  for (auto &BV : Opts.BuildVersions)1762    B.template addLoadCommand<MachO::LC_BUILD_VERSION>(1763        BV.Platform, BV.MinOS, BV.SDK, static_cast<uint32_t>(0));1764 1765  using LoadKind = MachOPlatform::HeaderOptions::LoadDylibCmd::LoadKind;1766  for (auto &LD : Opts.LoadDylibs) {1767    switch (LD.K) {1768    case LoadKind::Default:1769      B.template addLoadCommand<MachO::LC_LOAD_DYLIB>(1770          LD.D.Name, LD.D.Timestamp, LD.D.CurrentVersion,1771          LD.D.CompatibilityVersion);1772      break;1773    case LoadKind::Weak:1774      B.template addLoadCommand<MachO::LC_LOAD_WEAK_DYLIB>(1775          LD.D.Name, LD.D.Timestamp, LD.D.CurrentVersion,1776          LD.D.CompatibilityVersion);1777      break;1778    }1779  }1780  for (auto &P : Opts.RPaths)1781    B.template addLoadCommand<MachO::LC_RPATH>(P);1782 1783  auto HeaderContent = G.allocateBuffer(B.layout());1784  B.write(HeaderContent);1785 1786  return G.createContentBlock(HeaderSection, HeaderContent, ExecutorAddr(), 8,1787                              0);1788}1789 1790SimpleMachOHeaderMU::SimpleMachOHeaderMU(MachOPlatform &MOP,1791                                         SymbolStringPtr HeaderStartSymbol,1792                                         MachOPlatform::HeaderOptions Opts)1793    : MaterializationUnit(1794          createHeaderInterface(MOP, std::move(HeaderStartSymbol))),1795      MOP(MOP), Opts(std::move(Opts)) {}1796 1797void SimpleMachOHeaderMU::materialize(1798    std::unique_ptr<MaterializationResponsibility> R) {1799  auto G = createPlatformGraph(MOP, "<MachOHeaderMU>");1800  addMachOHeader(R->getTargetJITDylib(), *G, R->getInitializerSymbol());1801  MOP.getObjectLinkingLayer().emit(std::move(R), std::move(G));1802}1803 1804void SimpleMachOHeaderMU::discard(const JITDylib &JD,1805                                  const SymbolStringPtr &Sym) {}1806 1807void SimpleMachOHeaderMU::addMachOHeader(1808    JITDylib &JD, jitlink::LinkGraph &G,1809    const SymbolStringPtr &InitializerSymbol) {1810  auto &HeaderSection = G.createSection("__header", MemProt::Read);1811  auto &HeaderBlock = createHeaderBlock(JD, G, HeaderSection);1812 1813  // Init symbol is header-start symbol.1814  G.addDefinedSymbol(HeaderBlock, 0, *InitializerSymbol, HeaderBlock.getSize(),1815                     jitlink::Linkage::Strong, jitlink::Scope::Default, false,1816                     true);1817  for (auto &HS : AdditionalHeaderSymbols)1818    G.addDefinedSymbol(HeaderBlock, HS.Offset, HS.Name, HeaderBlock.getSize(),1819                       jitlink::Linkage::Strong, jitlink::Scope::Default, false,1820                       true);1821}1822 1823jitlink::Block &1824SimpleMachOHeaderMU::createHeaderBlock(JITDylib &JD, jitlink::LinkGraph &G,1825                                       jitlink::Section &HeaderSection) {1826  switch (MOP.getExecutionSession().getTargetTriple().getArch()) {1827  case Triple::aarch64:1828  case Triple::x86_64:1829    return ::createHeaderBlock<MachO64LE>(MOP, Opts, JD, G, HeaderSection);1830  default:1831    llvm_unreachable("Unsupported architecture");1832  }1833}1834 1835MaterializationUnit::Interface SimpleMachOHeaderMU::createHeaderInterface(1836    MachOPlatform &MOP, const SymbolStringPtr &HeaderStartSymbol) {1837  SymbolFlagsMap HeaderSymbolFlags;1838 1839  HeaderSymbolFlags[HeaderStartSymbol] = JITSymbolFlags::Exported;1840  for (auto &HS : AdditionalHeaderSymbols)1841    HeaderSymbolFlags[MOP.getExecutionSession().intern(HS.Name)] =1842        JITSymbolFlags::Exported;1843 1844  return MaterializationUnit::Interface(std::move(HeaderSymbolFlags),1845                                        HeaderStartSymbol);1846}1847 1848MachOHeaderInfo getMachOHeaderInfoFromTriple(const Triple &TT) {1849  switch (TT.getArch()) {1850  case Triple::aarch64:1851    return {/* PageSize   = */ 16 * 1024,1852            /* CPUType    = */ MachO::CPU_TYPE_ARM64,1853            /* CPUSubType = */ MachO::CPU_SUBTYPE_ARM64_ALL};1854  case Triple::x86_64:1855    return {/* PageSize   = */ 4 * 1024,1856            /* CPUType    = */ MachO::CPU_TYPE_X86_64,1857            /* CPUSubType = */ MachO::CPU_SUBTYPE_X86_64_ALL};1858  default:1859    llvm_unreachable("Unrecognized architecture");1860  }1861}1862 1863} // End namespace orc.1864} // End namespace llvm.1865