llvm.org GIT mirror llvm / 075c1e2 lib / ExecutionEngine / MCJIT / MCJIT.cpp
075c1e2

Tree @075c1e2 (Download .tar.gz)

MCJIT.cpp @075c1e2raw · history · blame

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
//===-- MCJIT.cpp - MC-based Just-in-Time Compiler ------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#include "MCJIT.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ExecutionEngine/GenericValue.h"
#include "llvm/ExecutionEngine/JITEventListener.h"
#include "llvm/ExecutionEngine/MCJIT.h"
#include "llvm/ExecutionEngine/SectionMemoryManager.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/IR/Mangler.h"
#include "llvm/IR/Module.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/Object/Archive.h"
#include "llvm/Object/ObjectFile.h"
#include "llvm/Support/DynamicLibrary.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/MutexGuard.h"

using namespace llvm;

void ObjectCache::anchor() {}

namespace {

static struct RegisterJIT {
  RegisterJIT() { MCJIT::Register(); }
} JITRegistrator;

}

extern "C" void LLVMLinkInMCJIT() {
}

ExecutionEngine*
MCJIT::createJIT(std::unique_ptr<Module> M,
                 std::string *ErrorStr,
                 std::shared_ptr<MCJITMemoryManager> MemMgr,
                 std::shared_ptr<JITSymbolResolver> Resolver,
                 std::unique_ptr<TargetMachine> TM) {
  // Try to register the program as a source of symbols to resolve against.
  //
  // FIXME: Don't do this here.
  sys::DynamicLibrary::LoadLibraryPermanently(nullptr, nullptr);

  if (!MemMgr || !Resolver) {
    auto RTDyldMM = std::make_shared<SectionMemoryManager>();
    if (!MemMgr)
      MemMgr = RTDyldMM;
    if (!Resolver)
      Resolver = RTDyldMM;
  }

  return new MCJIT(std::move(M), std::move(TM), std::move(MemMgr),
                   std::move(Resolver));
}

MCJIT::MCJIT(std::unique_ptr<Module> M, std::unique_ptr<TargetMachine> TM,
             std::shared_ptr<MCJITMemoryManager> MemMgr,
             std::shared_ptr<JITSymbolResolver> Resolver)
    : ExecutionEngine(TM->createDataLayout(), std::move(M)), TM(std::move(TM)),
      Ctx(nullptr), MemMgr(std::move(MemMgr)),
      Resolver(*this, std::move(Resolver)), Dyld(*this->MemMgr, this->Resolver),
      ObjCache(nullptr) {
  // FIXME: We are managing our modules, so we do not want the base class
  // ExecutionEngine to manage them as well. To avoid double destruction
  // of the first (and only) module added in ExecutionEngine constructor
  // we remove it from EE and will destruct it ourselves.
  //
  // It may make sense to move our module manager (based on SmallStPtr) back
  // into EE if the JIT and Interpreter can live with it.
  // If so, additional functions: addModule, removeModule, FindFunctionNamed,
  // runStaticConstructorsDestructors could be moved back to EE as well.
  //
  std::unique_ptr<Module> First = std::move(Modules[0]);
  Modules.clear();

  if (First->getDataLayout().isDefault())
    First->setDataLayout(getDataLayout());

  OwnedModules.addModule(std::move(First));
  RegisterJITEventListener(JITEventListener::createGDBRegistrationListener());
}

MCJIT::~MCJIT() {
  MutexGuard locked(lock);

  Dyld.deregisterEHFrames();

  for (auto &Obj : LoadedObjects)
    if (Obj)
      NotifyFreeingObject(*Obj);

  Archives.clear();
}

void MCJIT::addModule(std::unique_ptr<Module> M) {
  MutexGuard locked(lock);

  if (M->getDataLayout().isDefault())
    M->setDataLayout(getDataLayout());

  OwnedModules.addModule(std::move(M));
}

bool MCJIT::removeModule(Module *M) {
  MutexGuard locked(lock);
  return OwnedModules.removeModule(M);
}

void MCJIT::addObjectFile(std::unique_ptr<object::ObjectFile> Obj) {
  std::unique_ptr<RuntimeDyld::LoadedObjectInfo> L = Dyld.loadObject(*Obj);
  if (Dyld.hasError())
    report_fatal_error(Dyld.getErrorString());

  NotifyObjectEmitted(*Obj, *L);

  LoadedObjects.push_back(std::move(Obj));
}

void MCJIT::addObjectFile(object::OwningBinary<object::ObjectFile> Obj) {
  std::unique_ptr<object::ObjectFile> ObjFile;
  std::unique_ptr<MemoryBuffer> MemBuf;
  std::tie(ObjFile, MemBuf) = Obj.takeBinary();
  addObjectFile(std::move(ObjFile));
  Buffers.push_back(std::move(MemBuf));
}

void MCJIT::addArchive(object::OwningBinary<object::Archive> A) {
  Archives.push_back(std::move(A));
}

void MCJIT::setObjectCache(ObjectCache* NewCache) {
  MutexGuard locked(lock);
  ObjCache = NewCache;
}

std::unique_ptr<MemoryBuffer> MCJIT::emitObject(Module *M) {
  MutexGuard locked(lock);

  // This must be a module which has already been added but not loaded to this
  // MCJIT instance, since these conditions are tested by our caller,
  // generateCodeForModule.

  legacy::PassManager PM;

  // The RuntimeDyld will take ownership of this shortly
  SmallVector<char, 4096> ObjBufferSV;
  raw_svector_ostream ObjStream(ObjBufferSV);

  // Turn the machine code intermediate representation into bytes in memory
  // that may be executed.
  if (TM->addPassesToEmitMC(PM, Ctx, ObjStream, !getVerifyModules()))
    report_fatal_error("Target does not support MC emission!");

  // Initialize passes.
  PM.run(*M);
  // Flush the output buffer to get the generated code into memory

  std::unique_ptr<MemoryBuffer> CompiledObjBuffer(
                                new ObjectMemoryBuffer(std::move(ObjBufferSV)));

  // If we have an object cache, tell it about the new object.
  // Note that we're using the compiled image, not the loaded image (as below).
  if (ObjCache) {
    // MemoryBuffer is a thin wrapper around the actual memory, so it's OK
    // to create a temporary object here and delete it after the call.
    MemoryBufferRef MB = CompiledObjBuffer->getMemBufferRef();
    ObjCache->notifyObjectCompiled(M, MB);
  }

  return CompiledObjBuffer;
}

void MCJIT::generateCodeForModule(Module *M) {
  // Get a thread lock to make sure we aren't trying to load multiple times
  MutexGuard locked(lock);

  // This must be a module which has already been added to this MCJIT instance.
  assert(OwnedModules.ownsModule(M) &&
         "MCJIT::generateCodeForModule: Unknown module.");

  // Re-compilation is not supported
  if (OwnedModules.hasModuleBeenLoaded(M))
    return;

  std::unique_ptr<MemoryBuffer> ObjectToLoad;
  // Try to load the pre-compiled object from cache if possible
  if (ObjCache)
    ObjectToLoad = ObjCache->getObject(M);

  assert(M->getDataLayout() == getDataLayout() && "DataLayout Mismatch");

  // If the cache did not contain a suitable object, compile the object
  if (!ObjectToLoad) {
    ObjectToLoad = emitObject(M);
    assert(ObjectToLoad && "Compilation did not produce an object.");
  }

  // Load the object into the dynamic linker.
  // MCJIT now owns the ObjectImage pointer (via its LoadedObjects list).
  Expected<std::unique_ptr<object::ObjectFile>> LoadedObject =
    object::ObjectFile::createObjectFile(ObjectToLoad->getMemBufferRef());
  if (!LoadedObject) {
    std::string Buf;
    raw_string_ostream OS(Buf);
    logAllUnhandledErrors(LoadedObject.takeError(), OS, "");
    OS.flush();
    report_fatal_error(Buf);
  }
  std::unique_ptr<RuntimeDyld::LoadedObjectInfo> L =
    Dyld.loadObject(*LoadedObject.get());

  if (Dyld.hasError())
    report_fatal_error(Dyld.getErrorString());

  NotifyObjectEmitted(*LoadedObject.get(), *L);

  Buffers.push_back(std::move(ObjectToLoad));
  LoadedObjects.push_back(std::move(*LoadedObject));

  OwnedModules.markModuleAsLoaded(M);
}

void MCJIT::finalizeLoadedModules() {
  MutexGuard locked(lock);

  // Resolve any outstanding relocations.
  Dyld.resolveRelocations();

  OwnedModules.markAllLoadedModulesAsFinalized();

  // Register EH frame data for any module we own which has been loaded
  Dyld.registerEHFrames();

  // Set page permissions.
  MemMgr->finalizeMemory();
}

// FIXME: Rename this.
void MCJIT::finalizeObject() {
  MutexGuard locked(lock);

  // Generate code for module is going to move objects out of the 'added' list,
  // so we need to copy that out before using it:
  SmallVector<Module*, 16> ModsToAdd;
  for (auto M : OwnedModules.added())
    ModsToAdd.push_back(M);

  for (auto M : ModsToAdd)
    generateCodeForModule(M);

  finalizeLoadedModules();
}

void MCJIT::finalizeModule(Module *M) {
  MutexGuard locked(lock);

  // This must be a module which has already been added to this MCJIT instance.
  assert(OwnedModules.ownsModule(M) && "MCJIT::finalizeModule: Unknown module.");

  // If the module hasn't been compiled, just do that.
  if (!OwnedModules.hasModuleBeenLoaded(M))
    generateCodeForModule(M);

  finalizeLoadedModules();
}

JITSymbol MCJIT::findExistingSymbol(const std::string &Name) {
  SmallString<128> FullName;
  Mangler::getNameWithPrefix(FullName, Name, getDataLayout());

  if (void *Addr = getPointerToGlobalIfAvailable(FullName))
    return JITSymbol(static_cast<uint64_t>(
                         reinterpret_cast<uintptr_t>(Addr)),
                     JITSymbolFlags::Exported);

  return Dyld.getSymbol(FullName);
}

Module *MCJIT::findModuleForSymbol(const std::string &Name,
                                   bool CheckFunctionsOnly) {
  MutexGuard locked(lock);

  // If it hasn't already been generated, see if it's in one of our modules.
  for (ModulePtrSet::iterator I = OwnedModules.begin_added(),
                              E = OwnedModules.end_added();
       I != E; ++I) {
    Module *M = *I;
    Function *F = M->getFunction(Name);
    if (F && !F->isDeclaration())
      return M;
    if (!CheckFunctionsOnly) {
      GlobalVariable *G = M->getGlobalVariable(Name);
      if (G && !G->isDeclaration())
        return M;
      // FIXME: Do we need to worry about global aliases?
    }
  }
  // We didn't find the symbol in any of our modules.
  return nullptr;
}

uint64_t MCJIT::getSymbolAddress(const std::string &Name,
                                 bool CheckFunctionsOnly) {
  return findSymbol(Name, CheckFunctionsOnly).getAddress();
}

JITSymbol MCJIT::findSymbol(const std::string &Name,
                            bool CheckFunctionsOnly) {
  MutexGuard locked(lock);

  // First, check to see if we already have this symbol.
  if (auto Sym = findExistingSymbol(Name))
    return Sym;

  for (object::OwningBinary<object::Archive> &OB : Archives) {
    object::Archive *A = OB.getBinary();
    // Look for our symbols in each Archive
    auto OptionalChildOrErr = A->findSym(Name);
    if (!OptionalChildOrErr)
      report_fatal_error(OptionalChildOrErr.takeError());
    auto &OptionalChild = *OptionalChildOrErr;
    if (OptionalChild) {
      // FIXME: Support nested archives?
      Expected<std::unique_ptr<object::Binary>> ChildBinOrErr =
          OptionalChild->getAsBinary();
      if (!ChildBinOrErr) {
        // TODO: Actually report errors helpfully.
        consumeError(ChildBinOrErr.takeError());
        continue;
      }
      std::unique_ptr<object::Binary> &ChildBin = ChildBinOrErr.get();
      if (ChildBin->isObject()) {
        std::unique_ptr<object::ObjectFile> OF(
            static_cast<object::ObjectFile *>(ChildBin.release()));
        // This causes the object file to be loaded.
        addObjectFile(std::move(OF));
        // The address should be here now.
        if (auto Sym = findExistingSymbol(Name))
          return Sym;
      }
    }
  }

  // If it hasn't already been generated, see if it's in one of our modules.
  Module *M = findModuleForSymbol(Name, CheckFunctionsOnly);
  if (M) {
    generateCodeForModule(M);

    // Check the RuntimeDyld table again, it should be there now.
    return findExistingSymbol(Name);
  }

  // If a LazyFunctionCreator is installed, use it to get/create the function.
  // FIXME: Should we instead have a LazySymbolCreator callback?
  if (LazyFunctionCreator) {
    auto Addr = static_cast<uint64_t>(
                  reinterpret_cast<uintptr_t>(LazyFunctionCreator(Name)));
    return JITSymbol(Addr, JITSymbolFlags::Exported);
  }

  return nullptr;
}

uint64_t MCJIT::getGlobalValueAddress(const std::string &Name) {
  MutexGuard locked(lock);
  uint64_t Result = getSymbolAddress(Name, false);
  if (Result != 0)
    finalizeLoadedModules();
  return Result;
}

uint64_t MCJIT::getFunctionAddress(const std::string &Name) {
  MutexGuard locked(lock);
  uint64_t Result = getSymbolAddress(Name, true);
  if (Result != 0)
    finalizeLoadedModules();
  return Result;
}

// Deprecated.  Use getFunctionAddress instead.
void *MCJIT::getPointerToFunction(Function *F) {
  MutexGuard locked(lock);

  Mangler Mang;
  SmallString<128> Name;
  TM->getNameWithPrefix(Name, F, Mang);

  if (F->isDeclaration() || F->hasAvailableExternallyLinkage()) {
    bool AbortOnFailure = !F->hasExternalWeakLinkage();
    void *Addr = getPointerToNamedFunction(Name, AbortOnFailure);
    updateGlobalMapping(F, Addr);
    return Addr;
  }

  Module *M = F->getParent();
  bool HasBeenAddedButNotLoaded = OwnedModules.hasModuleBeenAddedButNotLoaded(M);

  // Make sure the relevant module has been compiled and loaded.
  if (HasBeenAddedButNotLoaded)
    generateCodeForModule(M);
  else if (!OwnedModules.hasModuleBeenLoaded(M)) {
    // If this function doesn't belong to one of our modules, we're done.
    // FIXME: Asking for the pointer to a function that hasn't been registered,
    //        and isn't a declaration (which is handled above) should probably
    //        be an assertion.
    return nullptr;
  }

  // FIXME: Should the Dyld be retaining module information? Probably not.
  //
  // This is the accessor for the target address, so make sure to check the
  // load address of the symbol, not the local address.
  return (void*)Dyld.getSymbol(Name).getAddress();
}

void MCJIT::runStaticConstructorsDestructorsInModulePtrSet(
    bool isDtors, ModulePtrSet::iterator I, ModulePtrSet::iterator E) {
  for (; I != E; ++I) {
    ExecutionEngine::runStaticConstructorsDestructors(**I, isDtors);
  }
}

void MCJIT::runStaticConstructorsDestructors(bool isDtors) {
  // Execute global ctors/dtors for each module in the program.
  runStaticConstructorsDestructorsInModulePtrSet(
      isDtors, OwnedModules.begin_added(), OwnedModules.end_added());
  runStaticConstructorsDestructorsInModulePtrSet(
      isDtors, OwnedModules.begin_loaded(), OwnedModules.end_loaded());
  runStaticConstructorsDestructorsInModulePtrSet(
      isDtors, OwnedModules.begin_finalized(), OwnedModules.end_finalized());
}

Function *MCJIT::FindFunctionNamedInModulePtrSet(const char *FnName,
                                                 ModulePtrSet::iterator I,
                                                 ModulePtrSet::iterator E) {
  for (; I != E; ++I) {
    Function *F = (*I)->getFunction(FnName);
    if (F && !F->isDeclaration())
      return F;
  }
  return nullptr;
}

GlobalVariable *MCJIT::FindGlobalVariableNamedInModulePtrSet(const char *Name,
                                                             bool AllowInternal,
                                                             ModulePtrSet::iterator I,
                                                             ModulePtrSet::iterator E) {
  for (; I != E; ++I) {
    GlobalVariable *GV = (*I)->getGlobalVariable(Name, AllowInternal);
    if (GV && !GV->isDeclaration())
      return GV;
  }
  return nullptr;
}


Function *MCJIT::FindFunctionNamed(const char *FnName) {
  Function *F = FindFunctionNamedInModulePtrSet(
      FnName, OwnedModules.begin_added(), OwnedModules.end_added());
  if (!F)
    F = FindFunctionNamedInModulePtrSet(FnName, OwnedModules.begin_loaded(),
                                        OwnedModules.end_loaded());
  if (!F)
    F = FindFunctionNamedInModulePtrSet(FnName, OwnedModules.begin_finalized(),
                                        OwnedModules.end_finalized());
  return F;
}

GlobalVariable *MCJIT::FindGlobalVariableNamed(const char *Name, bool AllowInternal) {
  GlobalVariable *GV = FindGlobalVariableNamedInModulePtrSet(
      Name, AllowInternal, OwnedModules.begin_added(), OwnedModules.end_added());
  if (!GV)
    GV = FindGlobalVariableNamedInModulePtrSet(Name, AllowInternal, OwnedModules.begin_loaded(),
                                        OwnedModules.end_loaded());
  if (!GV)
    GV = FindGlobalVariableNamedInModulePtrSet(Name, AllowInternal, OwnedModules.begin_finalized(),
                                        OwnedModules.end_finalized());
  return GV;
}

GenericValue MCJIT::runFunction(Function *F, ArrayRef<GenericValue> ArgValues) {
  assert(F && "Function *F was null at entry to run()");

  void *FPtr = getPointerToFunction(F);
  finalizeModule(F->getParent());
  assert(FPtr && "Pointer to fn's code was null after getPointerToFunction");
  FunctionType *FTy = F->getFunctionType();
  Type *RetTy = FTy->getReturnType();

  assert((FTy->getNumParams() == ArgValues.size() ||
          (FTy->isVarArg() && FTy->getNumParams() <= ArgValues.size())) &&
         "Wrong number of arguments passed into function!");
  assert(FTy->getNumParams() == ArgValues.size() &&
         "This doesn't support passing arguments through varargs (yet)!");

  // Handle some common cases first.  These cases correspond to common `main'
  // prototypes.
  if (RetTy->isIntegerTy(32) || RetTy->isVoidTy()) {
    switch (ArgValues.size()) {
    case 3:
      if (FTy->getParamType(0)->isIntegerTy(32) &&
          FTy->getParamType(1)->isPointerTy() &&
          FTy->getParamType(2)->isPointerTy()) {
        int (*PF)(int, char **, const char **) =
          (int(*)(int, char **, const char **))(intptr_t)FPtr;

        // Call the function.
        GenericValue rv;
        rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
                                 (char **)GVTOP(ArgValues[1]),
                                 (const char **)GVTOP(ArgValues[2])));
        return rv;
      }
      break;
    case 2:
      if (FTy->getParamType(0)->isIntegerTy(32) &&
          FTy->getParamType(1)->isPointerTy()) {
        int (*PF)(int, char **) = (int(*)(int, char **))(intptr_t)FPtr;

        // Call the function.
        GenericValue rv;
        rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
                                 (char **)GVTOP(ArgValues[1])));
        return rv;
      }
      break;
    case 1:
      if (FTy->getNumParams() == 1 &&
          FTy->getParamType(0)->isIntegerTy(32)) {
        GenericValue rv;
        int (*PF)(int) = (int(*)(int))(intptr_t)FPtr;
        rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue()));
        return rv;
      }
      break;
    }
  }

  // Handle cases where no arguments are passed first.
  if (ArgValues.empty()) {
    GenericValue rv;
    switch (RetTy->getTypeID()) {
    default: llvm_unreachable("Unknown return type for function call!");
    case Type::IntegerTyID: {
      unsigned BitWidth = cast<IntegerType>(RetTy)->getBitWidth();
      if (BitWidth == 1)
        rv.IntVal = APInt(BitWidth, ((bool(*)())(intptr_t)FPtr)());
      else if (BitWidth <= 8)
        rv.IntVal = APInt(BitWidth, ((char(*)())(intptr_t)FPtr)());
      else if (BitWidth <= 16)
        rv.IntVal = APInt(BitWidth, ((short(*)())(intptr_t)FPtr)());
      else if (BitWidth <= 32)
        rv.IntVal = APInt(BitWidth, ((int(*)())(intptr_t)FPtr)());
      else if (BitWidth <= 64)
        rv.IntVal = APInt(BitWidth, ((int64_t(*)())(intptr_t)FPtr)());
      else
        llvm_unreachable("Integer types > 64 bits not supported");
      return rv;
    }
    case Type::VoidTyID:
      rv.IntVal = APInt(32, ((int(*)())(intptr_t)FPtr)());
      return rv;
    case Type::FloatTyID:
      rv.FloatVal = ((float(*)())(intptr_t)FPtr)();
      return rv;
    case Type::DoubleTyID:
      rv.DoubleVal = ((double(*)())(intptr_t)FPtr)();
      return rv;
    case Type::X86_FP80TyID:
    case Type::FP128TyID:
    case Type::PPC_FP128TyID:
      llvm_unreachable("long double not supported yet");
    case Type::PointerTyID:
      return PTOGV(((void*(*)())(intptr_t)FPtr)());
    }
  }

  llvm_unreachable("Full-featured argument passing not supported yet!");
}

void *MCJIT::getPointerToNamedFunction(StringRef Name, bool AbortOnFailure) {
  if (!isSymbolSearchingDisabled()) {
    void *ptr =
      reinterpret_cast<void*>(
        static_cast<uintptr_t>(Resolver.findSymbol(Name).getAddress()));
    if (ptr)
      return ptr;
  }

  /// If a LazyFunctionCreator is installed, use it to get/create the function.
  if (LazyFunctionCreator)
    if (void *RP = LazyFunctionCreator(Name))
      return RP;

  if (AbortOnFailure) {
    report_fatal_error("Program used external function '"+Name+
                       "' which could not be resolved!");
  }
  return nullptr;
}

void MCJIT::RegisterJITEventListener(JITEventListener *L) {
  if (!L)
    return;
  MutexGuard locked(lock);
  EventListeners.push_back(L);
}

void MCJIT::UnregisterJITEventListener(JITEventListener *L) {
  if (!L)
    return;
  MutexGuard locked(lock);
  auto I = std::find(EventListeners.rbegin(), EventListeners.rend(), L);
  if (I != EventListeners.rend()) {
    std::swap(*I, EventListeners.back());
    EventListeners.pop_back();
  }
}

void MCJIT::NotifyObjectEmitted(const object::ObjectFile& Obj,
                                const RuntimeDyld::LoadedObjectInfo &L) {
  MutexGuard locked(lock);
  MemMgr->notifyObjectLoaded(this, Obj);
  for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) {
    EventListeners[I]->NotifyObjectEmitted(Obj, L);
  }
}

void MCJIT::NotifyFreeingObject(const object::ObjectFile& Obj) {
  MutexGuard locked(lock);
  for (JITEventListener *L : EventListeners)
    L->NotifyFreeingObject(Obj);
}

JITSymbol
LinkingSymbolResolver::findSymbol(const std::string &Name) {
  auto Result = ParentEngine.findSymbol(Name, false);
  // If the symbols wasn't found and it begins with an underscore, try again
  // without the underscore.
  if (!Result && Name[0] == '_')
    Result = ParentEngine.findSymbol(Name.substr(1), false);
  if (Result)
    return Result;
  if (ParentEngine.isSymbolSearchingDisabled())
    return nullptr;
  return ClientResolver->findSymbol(Name);
}