lib/ExecutionEngine/MCJIT/MCJIT.cpp

   1 //===-- MCJIT.cpp - MC-based Just-in-Time Compiler ------------------------===//
   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 "MCJIT.h"
  10 #include "llvm/ADT/STLExtras.h"
  11 #include "llvm/ExecutionEngine/GenericValue.h"
  12 #include "llvm/ExecutionEngine/JITEventListener.h"
  13 #include "llvm/ExecutionEngine/MCJIT.h"
  14 #include "llvm/ExecutionEngine/SectionMemoryManager.h"
  15 #include "llvm/IR/DataLayout.h"
  16 #include "llvm/IR/DerivedTypes.h"
  17 #include "llvm/IR/Function.h"
  18 #include "llvm/IR/LegacyPassManager.h"
  19 #include "llvm/IR/Mangler.h"
  20 #include "llvm/IR/Module.h"
  21 #include "llvm/Object/Archive.h"
  22 #include "llvm/Object/ObjectFile.h"
  23 #include "llvm/Support/DynamicLibrary.h"
  24 #include "llvm/Support/ErrorHandling.h"
  25 #include "llvm/Support/MemoryBuffer.h"
  26 #include <mutex>
  27
  28 using namespace llvm;
  29
  30 namespace {
  31
  32 static struct RegisterJIT {
  33   RegisterJIT() { MCJIT::Register(); }
  34 } JITRegistrator;
  35
  36 }
  37
  38 extern "C" void LLVMLinkInMCJIT() {
  39 }
  40
  41 ExecutionEngine *
  42 MCJIT::createJIT(std::unique_ptr<Module> M, std::string *ErrorStr,
  43                  std::shared_ptr<MCJITMemoryManager> MemMgr,
  44                  std::shared_ptr<LegacyJITSymbolResolver> Resolver,
  45                  std::unique_ptr<TargetMachine> TM) {
  46   // Try to register the program as a source of symbols to resolve against.
  47   //
  48   // FIXME: Don't do this here.
  49   sys::DynamicLibrary::LoadLibraryPermanently(nullptr, nullptr);
  50
  51   if (!MemMgr || !Resolver) {
  52     auto RTDyldMM = std::make_shared<SectionMemoryManager>();
  53     if (!MemMgr)
  54       MemMgr = RTDyldMM;
  55     if (!Resolver)
  56       Resolver = RTDyldMM;
  57   }
  58
  59   return new MCJIT(std::move(M), std::move(TM), std::move(MemMgr),
  60                    std::move(Resolver));
  61 }
  62
  63 MCJIT::MCJIT(std::unique_ptr<Module> M, std::unique_ptr<TargetMachine> TM,
  64              std::shared_ptr<MCJITMemoryManager> MemMgr,
  65              std::shared_ptr<LegacyJITSymbolResolver> Resolver)
  66     : ExecutionEngine(TM->createDataLayout(), std::move(M)), TM(std::move(TM)),
  67       Ctx(nullptr), MemMgr(std::move(MemMgr)),
  68       Resolver(*this, std::move(Resolver)), Dyld(*this->MemMgr, this->Resolver),
  69       ObjCache(nullptr) {
  70   // FIXME: We are managing our modules, so we do not want the base class
  71   // ExecutionEngine to manage them as well. To avoid double destruction
  72   // of the first (and only) module added in ExecutionEngine constructor
  73   // we remove it from EE and will destruct it ourselves.
  74   //
  75   // It may make sense to move our module manager (based on SmallStPtr) back
  76   // into EE if the JIT and Interpreter can live with it.
  77   // If so, additional functions: addModule, removeModule, FindFunctionNamed,
  78   // runStaticConstructorsDestructors could be moved back to EE as well.
  79   //
  80   std::unique_ptr<Module> First = std::move(Modules[0]);
  81   Modules.clear();
  82
  83   if (First->getDataLayout().isDefault())
  84     First->setDataLayout(getDataLayout());
  85
  86   OwnedModules.addModule(std::move(First));
  87   RegisterJITEventListener(JITEventListener::createGDBRegistrationListener());
  88 }
  89
  90 MCJIT::~MCJIT() {
  91   std::lock_guard<sys::Mutex> locked(lock);
  92
  93   Dyld.deregisterEHFrames();
  94
  95   for (auto &Obj : LoadedObjects)
  96     if (Obj)
  97       notifyFreeingObject(*Obj);
  98
  99   Archives.clear();
 100 }
 101
 102 void MCJIT::addModule(std::unique_ptr<Module> M) {
 103   std::lock_guard<sys::Mutex> locked(lock);
 104
 105   if (M->getDataLayout().isDefault())
 106     M->setDataLayout(getDataLayout());
 107
 108   OwnedModules.addModule(std::move(M));
 109 }
 110
 111 bool MCJIT::removeModule(Module *M) {
 112   std::lock_guard<sys::Mutex> locked(lock);
 113   return OwnedModules.removeModule(M);
 114 }
 115
 116 void MCJIT::addObjectFile(std::unique_ptr<object::ObjectFile> Obj) {
 117   std::unique_ptr<RuntimeDyld::LoadedObjectInfo> L = Dyld.loadObject(*Obj);
 118   if (Dyld.hasError())
 119     report_fatal_error(Dyld.getErrorString());
 120
 121   notifyObjectLoaded(*Obj, *L);
 122
 123   LoadedObjects.push_back(std::move(Obj));
 124 }
 125
 126 void MCJIT::addObjectFile(object::OwningBinary<object::ObjectFile> Obj) {
 127   std::unique_ptr<object::ObjectFile> ObjFile;
 128   std::unique_ptr<MemoryBuffer> MemBuf;
 129   std::tie(ObjFile, MemBuf) = Obj.takeBinary();
 130   addObjectFile(std::move(ObjFile));
 131   Buffers.push_back(std::move(MemBuf));
 132 }
 133
 134 void MCJIT::addArchive(object::OwningBinary<object::Archive> A) {
 135   Archives.push_back(std::move(A));
 136 }
 137
 138 void MCJIT::setObjectCache(ObjectCache* NewCache) {
 139   std::lock_guard<sys::Mutex> locked(lock);
 140   ObjCache = NewCache;
 141 }
 142
 143 std::unique_ptr<MemoryBuffer> MCJIT::emitObject(Module *M) {
 144   assert(M && "Can not emit a null module");
 145
 146   std::lock_guard<sys::Mutex> locked(lock);
 147
 148   // Materialize all globals in the module if they have not been
 149   // materialized already.
 150   cantFail(M->materializeAll());
 151
 152   // This must be a module which has already been added but not loaded to this
 153   // MCJIT instance, since these conditions are tested by our caller,
 154   // generateCodeForModule.
 155
 156   legacy::PassManager PM;
 157
 158   // The RuntimeDyld will take ownership of this shortly
 159   SmallVector<char, 4096> ObjBufferSV;
 160   raw_svector_ostream ObjStream(ObjBufferSV);
 161
 162   // Turn the machine code intermediate representation into bytes in memory
 163   // that may be executed.
 164   if (TM->addPassesToEmitMC(PM, Ctx, ObjStream, !getVerifyModules()))
 165     report_fatal_error("Target does not support MC emission!");
 166
 167   // Initialize passes.
 168   PM.run(*M);
 169   // Flush the output buffer to get the generated code into memory
 170
 171   std::unique_ptr<MemoryBuffer> CompiledObjBuffer(
 172       new SmallVectorMemoryBuffer(std::move(ObjBufferSV)));
 173
 174   // If we have an object cache, tell it about the new object.
 175   // Note that we're using the compiled image, not the loaded image (as below).
 176   if (ObjCache) {
 177     // MemoryBuffer is a thin wrapper around the actual memory, so it's OK
 178     // to create a temporary object here and delete it after the call.
 179     MemoryBufferRef MB = CompiledObjBuffer->getMemBufferRef();
 180     ObjCache->notifyObjectCompiled(M, MB);
 181   }
 182
 183   return CompiledObjBuffer;
 184 }
 185
 186 void MCJIT::generateCodeForModule(Module *M) {
 187   // Get a thread lock to make sure we aren't trying to load multiple times
 188   std::lock_guard<sys::Mutex> locked(lock);
 189
 190   // This must be a module which has already been added to this MCJIT instance.
 191   assert(OwnedModules.ownsModule(M) &&
 192          "MCJIT::generateCodeForModule: Unknown module.");
 193
 194   // Re-compilation is not supported
 195   if (OwnedModules.hasModuleBeenLoaded(M))
 196     return;
 197
 198   std::unique_ptr<MemoryBuffer> ObjectToLoad;
 199   // Try to load the pre-compiled object from cache if possible
 200   if (ObjCache)
 201     ObjectToLoad = ObjCache->getObject(M);
 202
 203   assert(M->getDataLayout() == getDataLayout() && "DataLayout Mismatch");
 204
 205   // If the cache did not contain a suitable object, compile the object
 206   if (!ObjectToLoad) {
 207     ObjectToLoad = emitObject(M);
 208     assert(ObjectToLoad && "Compilation did not produce an object.");
 209   }
 210
 211   // Load the object into the dynamic linker.
 212   // MCJIT now owns the ObjectImage pointer (via its LoadedObjects list).
 213   Expected<std::unique_ptr<object::ObjectFile>> LoadedObject =
 214     object::ObjectFile::createObjectFile(ObjectToLoad->getMemBufferRef());
 215   if (!LoadedObject) {
 216     std::string Buf;
 217     raw_string_ostream OS(Buf);
 218     logAllUnhandledErrors(LoadedObject.takeError(), OS);
 219     OS.flush();
 220     report_fatal_error(Buf);
 221   }
 222   std::unique_ptr<RuntimeDyld::LoadedObjectInfo> L =
 223     Dyld.loadObject(*LoadedObject.get());
 224
 225   if (Dyld.hasError())
 226     report_fatal_error(Dyld.getErrorString());
 227
 228   notifyObjectLoaded(*LoadedObject.get(), *L);
 229
 230   Buffers.push_back(std::move(ObjectToLoad));
 231   LoadedObjects.push_back(std::move(*LoadedObject));
 232
 233   OwnedModules.markModuleAsLoaded(M);
 234 }
 235
 236 void MCJIT::finalizeLoadedModules() {
 237   std::lock_guard<sys::Mutex> locked(lock);
 238
 239   // Resolve any outstanding relocations.
 240   Dyld.resolveRelocations();
 241
 242   OwnedModules.markAllLoadedModulesAsFinalized();
 243
 244   // Register EH frame data for any module we own which has been loaded
 245   Dyld.registerEHFrames();
 246
 247   // Set page permissions.
 248   MemMgr->finalizeMemory();
 249 }
 250
 251 // FIXME: Rename this.
 252 void MCJIT::finalizeObject() {
 253   std::lock_guard<sys::Mutex> locked(lock);
 254
 255   // Generate code for module is going to move objects out of the 'added' list,
 256   // so we need to copy that out before using it:
 257   SmallVector<Module*, 16> ModsToAdd;
 258   for (auto M : OwnedModules.added())
 259     ModsToAdd.push_back(M);
 260
 261   for (auto M : ModsToAdd)
 262     generateCodeForModule(M);
 263
 264   finalizeLoadedModules();
 265 }
 266
 267 void MCJIT::finalizeModule(Module *M) {
 268   std::lock_guard<sys::Mutex> locked(lock);
 269
 270   // This must be a module which has already been added to this MCJIT instance.
 271   assert(OwnedModules.ownsModule(M) && "MCJIT::finalizeModule: Unknown module.");
 272
 273   // If the module hasn't been compiled, just do that.
 274   if (!OwnedModules.hasModuleBeenLoaded(M))
 275     generateCodeForModule(M);
 276
 277   finalizeLoadedModules();
 278 }
 279
 280 JITSymbol MCJIT::findExistingSymbol(const std::string &Name) {
 281   if (void *Addr = getPointerToGlobalIfAvailable(Name))
 282     return JITSymbol(static_cast<uint64_t>(
 283                          reinterpret_cast<uintptr_t>(Addr)),
 284                      JITSymbolFlags::Exported);
 285
 286   return Dyld.getSymbol(Name);
 287 }
 288
 289 Module *MCJIT::findModuleForSymbol(const std::string &Name,
 290                                    bool CheckFunctionsOnly) {
 291   StringRef DemangledName = Name;
 292   if (DemangledName[0] == getDataLayout().getGlobalPrefix())
 293     DemangledName = DemangledName.substr(1);
 294
 295   std::lock_guard<sys::Mutex> locked(lock);
 296
 297   // If it hasn't already been generated, see if it's in one of our modules.
 298   for (ModulePtrSet::iterator I = OwnedModules.begin_added(),
 299                               E = OwnedModules.end_added();
 300        I != E; ++I) {
 301     Module *M = *I;
 302     Function *F = M->getFunction(DemangledName);
 303     if (F && !F->isDeclaration())
 304       return M;
 305     if (!CheckFunctionsOnly) {
 306       GlobalVariable *G = M->getGlobalVariable(DemangledName);
 307       if (G && !G->isDeclaration())
 308         return M;
 309       // FIXME: Do we need to worry about global aliases?
 310     }
 311   }
 312   // We didn't find the symbol in any of our modules.
 313   return nullptr;
 314 }
 315
 316 uint64_t MCJIT::getSymbolAddress(const std::string &Name,
 317                                  bool CheckFunctionsOnly) {
 318   std::string MangledName;
 319   {
 320     raw_string_ostream MangledNameStream(MangledName);
 321     Mangler::getNameWithPrefix(MangledNameStream, Name, getDataLayout());
 322   }
 323   if (auto Sym = findSymbol(MangledName, CheckFunctionsOnly)) {
 324     if (auto AddrOrErr = Sym.getAddress())
 325       return *AddrOrErr;
 326     else
 327       report_fatal_error(AddrOrErr.takeError());
 328   } else if (auto Err = Sym.takeError())
 329     report_fatal_error(Sym.takeError());
 330   return 0;
 331 }
 332
 333 JITSymbol MCJIT::findSymbol(const std::string &Name,
 334                             bool CheckFunctionsOnly) {
 335   std::lock_guard<sys::Mutex> locked(lock);
 336
 337   // First, check to see if we already have this symbol.
 338   if (auto Sym = findExistingSymbol(Name))
 339     return Sym;
 340
 341   for (object::OwningBinary<object::Archive> &OB : Archives) {
 342     object::Archive *A = OB.getBinary();
 343     // Look for our symbols in each Archive
 344     auto OptionalChildOrErr = A->findSym(Name);
 345     if (!OptionalChildOrErr)
 346       report_fatal_error(OptionalChildOrErr.takeError());
 347     auto &OptionalChild = *OptionalChildOrErr;
 348     if (OptionalChild) {
 349       // FIXME: Support nested archives?
 350       Expected<std::unique_ptr<object::Binary>> ChildBinOrErr =
 351           OptionalChild->getAsBinary();
 352       if (!ChildBinOrErr) {
 353         // TODO: Actually report errors helpfully.
 354         consumeError(ChildBinOrErr.takeError());
 355         continue;
 356       }
 357       std::unique_ptr<object::Binary> &ChildBin = ChildBinOrErr.get();
 358       if (ChildBin->isObject()) {
 359         std::unique_ptr<object::ObjectFile> OF(
 360             static_cast<object::ObjectFile *>(ChildBin.release()));
 361         // This causes the object file to be loaded.
 362         addObjectFile(std::move(OF));
 363         // The address should be here now.
 364         if (auto Sym = findExistingSymbol(Name))
 365           return Sym;
 366       }
 367     }
 368   }
 369
 370   // If it hasn't already been generated, see if it's in one of our modules.
 371   Module *M = findModuleForSymbol(Name, CheckFunctionsOnly);
 372   if (M) {
 373     generateCodeForModule(M);
 374
 375     // Check the RuntimeDyld table again, it should be there now.
 376     return findExistingSymbol(Name);
 377   }
 378
 379   // If a LazyFunctionCreator is installed, use it to get/create the function.
 380   // FIXME: Should we instead have a LazySymbolCreator callback?
 381   if (LazyFunctionCreator) {
 382     auto Addr = static_cast<uint64_t>(
 383                   reinterpret_cast<uintptr_t>(LazyFunctionCreator(Name)));
 384     return JITSymbol(Addr, JITSymbolFlags::Exported);
 385   }
 386
 387   return nullptr;
 388 }
 389
 390 uint64_t MCJIT::getGlobalValueAddress(const std::string &Name) {
 391   std::lock_guard<sys::Mutex> locked(lock);
 392   uint64_t Result = getSymbolAddress(Name, false);
 393   if (Result != 0)
 394     finalizeLoadedModules();
 395   return Result;
 396 }
 397
 398 uint64_t MCJIT::getFunctionAddress(const std::string &Name) {
 399   std::lock_guard<sys::Mutex> locked(lock);
 400   uint64_t Result = getSymbolAddress(Name, true);
 401   if (Result != 0)
 402     finalizeLoadedModules();
 403   return Result;
 404 }
 405
 406 // Deprecated.  Use getFunctionAddress instead.
 407 void *MCJIT::getPointerToFunction(Function *F) {
 408   std::lock_guard<sys::Mutex> locked(lock);
 409
 410   Mangler Mang;
 411   SmallString<128> Name;
 412   TM->getNameWithPrefix(Name, F, Mang);
 413
 414   if (F->isDeclaration() || F->hasAvailableExternallyLinkage()) {
 415     bool AbortOnFailure = !F->hasExternalWeakLinkage();
 416     void *Addr = getPointerToNamedFunction(Name, AbortOnFailure);
 417     updateGlobalMapping(F, Addr);
 418     return Addr;
 419   }
 420
 421   Module *M = F->getParent();
 422   bool HasBeenAddedButNotLoaded = OwnedModules.hasModuleBeenAddedButNotLoaded(M);
 423
 424   // Make sure the relevant module has been compiled and loaded.
 425   if (HasBeenAddedButNotLoaded)
 426     generateCodeForModule(M);
 427   else if (!OwnedModules.hasModuleBeenLoaded(M)) {
 428     // If this function doesn't belong to one of our modules, we're done.
 429     // FIXME: Asking for the pointer to a function that hasn't been registered,
 430     //        and isn't a declaration (which is handled above) should probably
 431     //        be an assertion.
 432     return nullptr;
 433   }
 434
 435   // FIXME: Should the Dyld be retaining module information? Probably not.
 436   //
 437   // This is the accessor for the target address, so make sure to check the
 438   // load address of the symbol, not the local address.
 439   return (void*)Dyld.getSymbol(Name).getAddress();
 440 }
 441
 442 void MCJIT::runStaticConstructorsDestructorsInModulePtrSet(
 443     bool isDtors, ModulePtrSet::iterator I, ModulePtrSet::iterator E) {
 444   for (; I != E; ++I) {
 445     ExecutionEngine::runStaticConstructorsDestructors(**I, isDtors);
 446   }
 447 }
 448
 449 void MCJIT::runStaticConstructorsDestructors(bool isDtors) {
 450   // Execute global ctors/dtors for each module in the program.
 451   runStaticConstructorsDestructorsInModulePtrSet(
 452       isDtors, OwnedModules.begin_added(), OwnedModules.end_added());
 453   runStaticConstructorsDestructorsInModulePtrSet(
 454       isDtors, OwnedModules.begin_loaded(), OwnedModules.end_loaded());
 455   runStaticConstructorsDestructorsInModulePtrSet(
 456       isDtors, OwnedModules.begin_finalized(), OwnedModules.end_finalized());
 457 }
 458
 459 Function *MCJIT::FindFunctionNamedInModulePtrSet(StringRef FnName,
 460                                                  ModulePtrSet::iterator I,
 461                                                  ModulePtrSet::iterator E) {
 462   for (; I != E; ++I) {
 463     Function *F = (*I)->getFunction(FnName);
 464     if (F && !F->isDeclaration())
 465       return F;
 466   }
 467   return nullptr;
 468 }
 469
 470 GlobalVariable *MCJIT::FindGlobalVariableNamedInModulePtrSet(StringRef Name,
 471                                                              bool AllowInternal,
 472                                                              ModulePtrSet::iterator I,
 473                                                              ModulePtrSet::iterator E) {
 474   for (; I != E; ++I) {
 475     GlobalVariable *GV = (*I)->getGlobalVariable(Name, AllowInternal);
 476     if (GV && !GV->isDeclaration())
 477       return GV;
 478   }
 479   return nullptr;
 480 }
 481
 482
 483 Function *MCJIT::FindFunctionNamed(StringRef FnName) {
 484   Function *F = FindFunctionNamedInModulePtrSet(
 485       FnName, OwnedModules.begin_added(), OwnedModules.end_added());
 486   if (!F)
 487     F = FindFunctionNamedInModulePtrSet(FnName, OwnedModules.begin_loaded(),
 488                                         OwnedModules.end_loaded());
 489   if (!F)
 490     F = FindFunctionNamedInModulePtrSet(FnName, OwnedModules.begin_finalized(),
 491                                         OwnedModules.end_finalized());
 492   return F;
 493 }
 494
 495 GlobalVariable *MCJIT::FindGlobalVariableNamed(StringRef Name, bool AllowInternal) {
 496   GlobalVariable *GV = FindGlobalVariableNamedInModulePtrSet(
 497       Name, AllowInternal, OwnedModules.begin_added(), OwnedModules.end_added());
 498   if (!GV)
 499     GV = FindGlobalVariableNamedInModulePtrSet(Name, AllowInternal, OwnedModules.begin_loaded(),
 500                                         OwnedModules.end_loaded());
 501   if (!GV)
 502     GV = FindGlobalVariableNamedInModulePtrSet(Name, AllowInternal, OwnedModules.begin_finalized(),
 503                                         OwnedModules.end_finalized());
 504   return GV;
 505 }
 506
 507 GenericValue MCJIT::runFunction(Function *F, ArrayRef<GenericValue> ArgValues) {
 508   assert(F && "Function *F was null at entry to run()");
 509
 510   void *FPtr = getPointerToFunction(F);
 511   finalizeModule(F->getParent());
 512   assert(FPtr && "Pointer to fn's code was null after getPointerToFunction");
 513   FunctionType *FTy = F->getFunctionType();
 514   Type *RetTy = FTy->getReturnType();
 515
 516   assert((FTy->getNumParams() == ArgValues.size() ||
 517           (FTy->isVarArg() && FTy->getNumParams() <= ArgValues.size())) &&
 518          "Wrong number of arguments passed into function!");
 519   assert(FTy->getNumParams() == ArgValues.size() &&
 520          "This doesn't support passing arguments through varargs (yet)!");
 521
 522   // Handle some common cases first.  These cases correspond to common `main'
 523   // prototypes.
 524   if (RetTy->isIntegerTy(32) || RetTy->isVoidTy()) {
 525     switch (ArgValues.size()) {
 526     case 3:
 527       if (FTy->getParamType(0)->isIntegerTy(32) &&
 528           FTy->getParamType(1)->isPointerTy() &&
 529           FTy->getParamType(2)->isPointerTy()) {
 530         int (*PF)(int, char **, const char **) =
 531           (int(*)(int, char **, const char **))(intptr_t)FPtr;
 532
 533         // Call the function.
 534         GenericValue rv;
 535         rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
 536                                  (char **)GVTOP(ArgValues[1]),
 537                                  (const char **)GVTOP(ArgValues[2])));
 538         return rv;
 539       }
 540       break;
 541     case 2:
 542       if (FTy->getParamType(0)->isIntegerTy(32) &&
 543           FTy->getParamType(1)->isPointerTy()) {
 544         int (*PF)(int, char **) = (int(*)(int, char **))(intptr_t)FPtr;
 545
 546         // Call the function.
 547         GenericValue rv;
 548         rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
 549                                  (char **)GVTOP(ArgValues[1])));
 550         return rv;
 551       }
 552       break;
 553     case 1:
 554       if (FTy->getNumParams() == 1 &&
 555           FTy->getParamType(0)->isIntegerTy(32)) {
 556         GenericValue rv;
 557         int (*PF)(int) = (int(*)(int))(intptr_t)FPtr;
 558         rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue()));
 559         return rv;
 560       }
 561       break;
 562     }
 563   }
 564
 565   // Handle cases where no arguments are passed first.
 566   if (ArgValues.empty()) {
 567     GenericValue rv;
 568     switch (RetTy->getTypeID()) {
 569     default: llvm_unreachable("Unknown return type for function call!");
 570     case Type::IntegerTyID: {
 571       unsigned BitWidth = cast<IntegerType>(RetTy)->getBitWidth();
 572       if (BitWidth == 1)
 573         rv.IntVal = APInt(BitWidth, ((bool(*)())(intptr_t)FPtr)());
 574       else if (BitWidth <= 8)
 575         rv.IntVal = APInt(BitWidth, ((char(*)())(intptr_t)FPtr)());
 576       else if (BitWidth <= 16)
 577         rv.IntVal = APInt(BitWidth, ((short(*)())(intptr_t)FPtr)());
 578       else if (BitWidth <= 32)
 579         rv.IntVal = APInt(BitWidth, ((int(*)())(intptr_t)FPtr)());
 580       else if (BitWidth <= 64)
 581         rv.IntVal = APInt(BitWidth, ((int64_t(*)())(intptr_t)FPtr)());
 582       else
 583         llvm_unreachable("Integer types > 64 bits not supported");
 584       return rv;
 585     }
 586     case Type::VoidTyID:
 587       rv.IntVal = APInt(32, ((int(*)())(intptr_t)FPtr)());
 588       return rv;
 589     case Type::FloatTyID:
 590       rv.FloatVal = ((float(*)())(intptr_t)FPtr)();
 591       return rv;
 592     case Type::DoubleTyID:
 593       rv.DoubleVal = ((double(*)())(intptr_t)FPtr)();
 594       return rv;
 595     case Type::X86_FP80TyID:
 596     case Type::FP128TyID:
 597     case Type::PPC_FP128TyID:
 598       llvm_unreachable("long double not supported yet");
 599     case Type::PointerTyID:
 600       return PTOGV(((void*(*)())(intptr_t)FPtr)());
 601     }
 602   }
 603
 604   report_fatal_error("MCJIT::runFunction does not support full-featured "
 605                      "argument passing. Please use "
 606                      "ExecutionEngine::getFunctionAddress and cast the result "
 607                      "to the desired function pointer type.");
 608 }
 609
 610 void *MCJIT::getPointerToNamedFunction(StringRef Name, bool AbortOnFailure) {
 611   if (!isSymbolSearchingDisabled()) {
 612     if (auto Sym = Resolver.findSymbol(Name)) {
 613       if (auto AddrOrErr = Sym.getAddress())
 614         return reinterpret_cast<void*>(
 615                  static_cast<uintptr_t>(*AddrOrErr));
 616     } else if (auto Err = Sym.takeError())
 617       report_fatal_error(std::move(Err));
 618   }
 619
 620   /// If a LazyFunctionCreator is installed, use it to get/create the function.
 621   if (LazyFunctionCreator)
 622     if (void *RP = LazyFunctionCreator(Name))
 623       return RP;
 624
 625   if (AbortOnFailure) {
 626     report_fatal_error("Program used external function '"+Name+
 627                        "' which could not be resolved!");
 628   }
 629   return nullptr;
 630 }
 631
 632 void MCJIT::RegisterJITEventListener(JITEventListener *L) {
 633   if (!L)
 634     return;
 635   std::lock_guard<sys::Mutex> locked(lock);
 636   EventListeners.push_back(L);
 637 }
 638
 639 void MCJIT::UnregisterJITEventListener(JITEventListener *L) {
 640   if (!L)
 641     return;
 642   std::lock_guard<sys::Mutex> locked(lock);
 643   auto I = find(reverse(EventListeners), L);
 644   if (I != EventListeners.rend()) {
 645     std::swap(*I, EventListeners.back());
 646     EventListeners.pop_back();
 647   }
 648 }
 649
 650 void MCJIT::notifyObjectLoaded(const object::ObjectFile &Obj,
 651                                const RuntimeDyld::LoadedObjectInfo &L) {
 652   uint64_t Key =
 653       static_cast<uint64_t>(reinterpret_cast<uintptr_t>(Obj.getData().data()));
 654   std::lock_guard<sys::Mutex> locked(lock);
 655   MemMgr->notifyObjectLoaded(this, Obj);
 656   for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) {
 657     EventListeners[I]->notifyObjectLoaded(Key, Obj, L);
 658   }
 659 }
 660
 661 void MCJIT::notifyFreeingObject(const object::ObjectFile &Obj) {
 662   uint64_t Key =
 663       static_cast<uint64_t>(reinterpret_cast<uintptr_t>(Obj.getData().data()));
 664   std::lock_guard<sys::Mutex> locked(lock);
 665   for (JITEventListener *L : EventListeners)
 666     L->notifyFreeingObject(Key);
 667 }
 668
 669 JITSymbol
 670 LinkingSymbolResolver::findSymbol(const std::string &Name) {
 671   auto Result = ParentEngine.findSymbol(Name, false);
 672   if (Result)
 673     return Result;
 674   if (ParentEngine.isSymbolSearchingDisabled())
 675     return nullptr;
 676   return ClientResolver->findSymbol(Name);
 677 }
 678
 679 void LinkingSymbolResolver::anchor() {}