1//===-- JIT.cpp - LLVM Just in Time Compiler ------------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This tool implements a just-in-time compiler for LLVM, allowing direct
11// execution of LLVM bitcode in an efficient manner.
12//
13//===----------------------------------------------------------------------===//
14
15#include "JIT.h"
16#include "llvm/ADT/SmallPtrSet.h"
17#include "llvm/CodeGen/JITCodeEmitter.h"
18#include "llvm/CodeGen/MachineCodeInfo.h"
19#include "llvm/Config/config.h"
20#include "llvm/ExecutionEngine/GenericValue.h"
21#include "llvm/ExecutionEngine/JITEventListener.h"
22#include "llvm/ExecutionEngine/JITMemoryManager.h"
23#include "llvm/IR/Constants.h"
24#include "llvm/IR/DataLayout.h"
25#include "llvm/IR/DerivedTypes.h"
26#include "llvm/IR/Function.h"
27#include "llvm/IR/GlobalVariable.h"
28#include "llvm/IR/Instructions.h"
29#include "llvm/IR/Module.h"
30#include "llvm/Support/Dwarf.h"
31#include "llvm/Support/DynamicLibrary.h"
32#include "llvm/Support/ErrorHandling.h"
33#include "llvm/Support/ManagedStatic.h"
34#include "llvm/Support/MutexGuard.h"
35#include "llvm/Target/TargetJITInfo.h"
36#include "llvm/Target/TargetMachine.h"
37
38using namespace llvm;
39
40#ifdef __APPLE__
41// Apple gcc defaults to -fuse-cxa-atexit (i.e. calls __cxa_atexit instead
42// of atexit). It passes the address of linker generated symbol __dso_handle
43// to the function.
44// This configuration change happened at version 5330.
45# include <AvailabilityMacros.h>
46# if defined(MAC_OS_X_VERSION_10_4) && \
47     ((MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_4) || \
48      (MAC_OS_X_VERSION_MIN_REQUIRED == MAC_OS_X_VERSION_10_4 && \
49       __APPLE_CC__ >= 5330))
50#  ifndef HAVE___DSO_HANDLE
51#   define HAVE___DSO_HANDLE 1
52#  endif
53# endif
54#endif
55
56#if HAVE___DSO_HANDLE
57extern void *__dso_handle __attribute__ ((__visibility__ ("hidden")));
58#endif
59
60namespace {
61
62static struct RegisterJIT {
63  RegisterJIT() { JIT::Register(); }
64} JITRegistrator;
65
66}
67
68extern "C" void LLVMLinkInJIT() {
69}
70
71/// createJIT - This is the factory method for creating a JIT for the current
72/// machine, it does not fall back to the interpreter.  This takes ownership
73/// of the module.
74ExecutionEngine *JIT::createJIT(Module *M,
75                                std::string *ErrorStr,
76                                JITMemoryManager *JMM,
77                                bool GVsWithCode,
78                                TargetMachine *TM) {
79  // Try to register the program as a source of symbols to resolve against.
80  //
81  // FIXME: Don't do this here.
82  sys::DynamicLibrary::LoadLibraryPermanently(nullptr, nullptr);
83
84  // If the target supports JIT code generation, create the JIT.
85  if (TargetJITInfo *TJ = TM->getJITInfo()) {
86    return new JIT(M, *TM, *TJ, JMM, GVsWithCode);
87  } else {
88    if (ErrorStr)
89      *ErrorStr = "target does not support JIT code generation";
90    return nullptr;
91  }
92}
93
94namespace {
95/// This class supports the global getPointerToNamedFunction(), which allows
96/// bugpoint or gdb users to search for a function by name without any context.
97class JitPool {
98  SmallPtrSet<JIT*, 1> JITs;  // Optimize for process containing just 1 JIT.
99  mutable sys::Mutex Lock;
100public:
101  void Add(JIT *jit) {
102    MutexGuard guard(Lock);
103    JITs.insert(jit);
104  }
105  void Remove(JIT *jit) {
106    MutexGuard guard(Lock);
107    JITs.erase(jit);
108  }
109  void *getPointerToNamedFunction(const char *Name) const {
110    MutexGuard guard(Lock);
111    assert(JITs.size() != 0 && "No Jit registered");
112    //search function in every instance of JIT
113    for (SmallPtrSet<JIT*, 1>::const_iterator Jit = JITs.begin(),
114           end = JITs.end();
115         Jit != end; ++Jit) {
116      if (Function *F = (*Jit)->FindFunctionNamed(Name))
117        return (*Jit)->getPointerToFunction(F);
118    }
119    // The function is not available : fallback on the first created (will
120    // search in symbol of the current program/library)
121    return (*JITs.begin())->getPointerToNamedFunction(Name);
122  }
123};
124ManagedStatic<JitPool> AllJits;
125}
126extern "C" {
127  // getPointerToNamedFunction - This function is used as a global wrapper to
128  // JIT::getPointerToNamedFunction for the purpose of resolving symbols when
129  // bugpoint is debugging the JIT. In that scenario, we are loading an .so and
130  // need to resolve function(s) that are being mis-codegenerated, so we need to
131  // resolve their addresses at runtime, and this is the way to do it.
132  void *getPointerToNamedFunction(const char *Name) {
133    return AllJits->getPointerToNamedFunction(Name);
134  }
135}
136
137JIT::JIT(Module *M, TargetMachine &tm, TargetJITInfo &tji,
138         JITMemoryManager *jmm, bool GVsWithCode)
139  : ExecutionEngine(M), TM(tm), TJI(tji),
140    JMM(jmm ? jmm : JITMemoryManager::CreateDefaultMemManager()),
141    AllocateGVsWithCode(GVsWithCode), isAlreadyCodeGenerating(false) {
142  setDataLayout(TM.getDataLayout());
143
144  jitstate = new JITState(M);
145
146  // Initialize JCE
147  JCE = createEmitter(*this, JMM, TM);
148
149  // Register in global list of all JITs.
150  AllJits->Add(this);
151
152  // Add target data
153  MutexGuard locked(lock);
154  FunctionPassManager &PM = jitstate->getPM();
155  M->setDataLayout(TM.getDataLayout());
156  PM.add(new DataLayoutPass(M));
157
158  // Turn the machine code intermediate representation into bytes in memory that
159  // may be executed.
160  if (TM.addPassesToEmitMachineCode(PM, *JCE, !getVerifyModules())) {
161    report_fatal_error("Target does not support machine code emission!");
162  }
163
164  // Initialize passes.
165  PM.doInitialization();
166}
167
168JIT::~JIT() {
169  // Cleanup.
170  AllJits->Remove(this);
171  delete jitstate;
172  delete JCE;
173  // JMM is a ownership of JCE, so we no need delete JMM here.
174  delete &TM;
175}
176
177/// addModule - Add a new Module to the JIT.  If we previously removed the last
178/// Module, we need re-initialize jitstate with a valid Module.
179void JIT::addModule(Module *M) {
180  MutexGuard locked(lock);
181
182  if (Modules.empty()) {
183    assert(!jitstate && "jitstate should be NULL if Modules vector is empty!");
184
185    jitstate = new JITState(M);
186
187    FunctionPassManager &PM = jitstate->getPM();
188    M->setDataLayout(TM.getDataLayout());
189    PM.add(new DataLayoutPass(M));
190
191    // Turn the machine code intermediate representation into bytes in memory
192    // that may be executed.
193    if (TM.addPassesToEmitMachineCode(PM, *JCE, !getVerifyModules())) {
194      report_fatal_error("Target does not support machine code emission!");
195    }
196
197    // Initialize passes.
198    PM.doInitialization();
199  }
200
201  ExecutionEngine::addModule(M);
202}
203
204/// removeModule - If we are removing the last Module, invalidate the jitstate
205/// since the PassManager it contains references a released Module.
206bool JIT::removeModule(Module *M) {
207  bool result = ExecutionEngine::removeModule(M);
208
209  MutexGuard locked(lock);
210
211  if (jitstate && jitstate->getModule() == M) {
212    delete jitstate;
213    jitstate = nullptr;
214  }
215
216  if (!jitstate && !Modules.empty()) {
217    jitstate = new JITState(Modules[0]);
218
219    FunctionPassManager &PM = jitstate->getPM();
220    M->setDataLayout(TM.getDataLayout());
221    PM.add(new DataLayoutPass(M));
222
223    // Turn the machine code intermediate representation into bytes in memory
224    // that may be executed.
225    if (TM.addPassesToEmitMachineCode(PM, *JCE, !getVerifyModules())) {
226      report_fatal_error("Target does not support machine code emission!");
227    }
228
229    // Initialize passes.
230    PM.doInitialization();
231  }
232  return result;
233}
234
235/// run - Start execution with the specified function and arguments.
236///
237GenericValue JIT::runFunction(Function *F,
238                              const std::vector<GenericValue> &ArgValues) {
239  assert(F && "Function *F was null at entry to run()");
240
241  void *FPtr = getPointerToFunction(F);
242  assert(FPtr && "Pointer to fn's code was null after getPointerToFunction");
243  FunctionType *FTy = F->getFunctionType();
244  Type *RetTy = FTy->getReturnType();
245
246  assert((FTy->getNumParams() == ArgValues.size() ||
247          (FTy->isVarArg() && FTy->getNumParams() <= ArgValues.size())) &&
248         "Wrong number of arguments passed into function!");
249  assert(FTy->getNumParams() == ArgValues.size() &&
250         "This doesn't support passing arguments through varargs (yet)!");
251
252  // Handle some common cases first.  These cases correspond to common `main'
253  // prototypes.
254  if (RetTy->isIntegerTy(32) || RetTy->isVoidTy()) {
255    switch (ArgValues.size()) {
256    case 3:
257      if (FTy->getParamType(0)->isIntegerTy(32) &&
258          FTy->getParamType(1)->isPointerTy() &&
259          FTy->getParamType(2)->isPointerTy()) {
260        int (*PF)(int, char **, const char **) =
261          (int(*)(int, char **, const char **))(intptr_t)FPtr;
262
263        // Call the function.
264        GenericValue rv;
265        rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
266                                 (char **)GVTOP(ArgValues[1]),
267                                 (const char **)GVTOP(ArgValues[2])));
268        return rv;
269      }
270      break;
271    case 2:
272      if (FTy->getParamType(0)->isIntegerTy(32) &&
273          FTy->getParamType(1)->isPointerTy()) {
274        int (*PF)(int, char **) = (int(*)(int, char **))(intptr_t)FPtr;
275
276        // Call the function.
277        GenericValue rv;
278        rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
279                                 (char **)GVTOP(ArgValues[1])));
280        return rv;
281      }
282      break;
283    case 1:
284      if (FTy->getParamType(0)->isIntegerTy(32)) {
285        GenericValue rv;
286        int (*PF)(int) = (int(*)(int))(intptr_t)FPtr;
287        rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue()));
288        return rv;
289      }
290      if (FTy->getParamType(0)->isPointerTy()) {
291        GenericValue rv;
292        int (*PF)(char *) = (int(*)(char *))(intptr_t)FPtr;
293        rv.IntVal = APInt(32, PF((char*)GVTOP(ArgValues[0])));
294        return rv;
295      }
296      break;
297    }
298  }
299
300  // Handle cases where no arguments are passed first.
301  if (ArgValues.empty()) {
302    GenericValue rv;
303    switch (RetTy->getTypeID()) {
304    default: llvm_unreachable("Unknown return type for function call!");
305    case Type::IntegerTyID: {
306      unsigned BitWidth = cast<IntegerType>(RetTy)->getBitWidth();
307      if (BitWidth == 1)
308        rv.IntVal = APInt(BitWidth, ((bool(*)())(intptr_t)FPtr)());
309      else if (BitWidth <= 8)
310        rv.IntVal = APInt(BitWidth, ((char(*)())(intptr_t)FPtr)());
311      else if (BitWidth <= 16)
312        rv.IntVal = APInt(BitWidth, ((short(*)())(intptr_t)FPtr)());
313      else if (BitWidth <= 32)
314        rv.IntVal = APInt(BitWidth, ((int(*)())(intptr_t)FPtr)());
315      else if (BitWidth <= 64)
316        rv.IntVal = APInt(BitWidth, ((int64_t(*)())(intptr_t)FPtr)());
317      else
318        llvm_unreachable("Integer types > 64 bits not supported");
319      return rv;
320    }
321    case Type::VoidTyID:
322      rv.IntVal = APInt(32, ((int(*)())(intptr_t)FPtr)());
323      return rv;
324    case Type::FloatTyID:
325      rv.FloatVal = ((float(*)())(intptr_t)FPtr)();
326      return rv;
327    case Type::DoubleTyID:
328      rv.DoubleVal = ((double(*)())(intptr_t)FPtr)();
329      return rv;
330    case Type::X86_FP80TyID:
331    case Type::FP128TyID:
332    case Type::PPC_FP128TyID:
333      llvm_unreachable("long double not supported yet");
334    case Type::PointerTyID:
335      return PTOGV(((void*(*)())(intptr_t)FPtr)());
336    }
337  }
338
339  // Okay, this is not one of our quick and easy cases.  Because we don't have a
340  // full FFI, we have to codegen a nullary stub function that just calls the
341  // function we are interested in, passing in constants for all of the
342  // arguments.  Make this function and return.
343
344  // First, create the function.
345  FunctionType *STy=FunctionType::get(RetTy, false);
346  Function *Stub = Function::Create(STy, Function::InternalLinkage, "",
347                                    F->getParent());
348
349  // Insert a basic block.
350  BasicBlock *StubBB = BasicBlock::Create(F->getContext(), "", Stub);
351
352  // Convert all of the GenericValue arguments over to constants.  Note that we
353  // currently don't support varargs.
354  SmallVector<Value*, 8> Args;
355  for (unsigned i = 0, e = ArgValues.size(); i != e; ++i) {
356    Constant *C = nullptr;
357    Type *ArgTy = FTy->getParamType(i);
358    const GenericValue &AV = ArgValues[i];
359    switch (ArgTy->getTypeID()) {
360    default: llvm_unreachable("Unknown argument type for function call!");
361    case Type::IntegerTyID:
362        C = ConstantInt::get(F->getContext(), AV.IntVal);
363        break;
364    case Type::FloatTyID:
365        C = ConstantFP::get(F->getContext(), APFloat(AV.FloatVal));
366        break;
367    case Type::DoubleTyID:
368        C = ConstantFP::get(F->getContext(), APFloat(AV.DoubleVal));
369        break;
370    case Type::PPC_FP128TyID:
371    case Type::X86_FP80TyID:
372    case Type::FP128TyID:
373        C = ConstantFP::get(F->getContext(), APFloat(ArgTy->getFltSemantics(),
374                                                     AV.IntVal));
375        break;
376    case Type::PointerTyID:
377      void *ArgPtr = GVTOP(AV);
378      if (sizeof(void*) == 4)
379        C = ConstantInt::get(Type::getInt32Ty(F->getContext()),
380                             (int)(intptr_t)ArgPtr);
381      else
382        C = ConstantInt::get(Type::getInt64Ty(F->getContext()),
383                             (intptr_t)ArgPtr);
384      // Cast the integer to pointer
385      C = ConstantExpr::getIntToPtr(C, ArgTy);
386      break;
387    }
388    Args.push_back(C);
389  }
390
391  CallInst *TheCall = CallInst::Create(F, Args, "", StubBB);
392  TheCall->setCallingConv(F->getCallingConv());
393  TheCall->setTailCall();
394  if (!TheCall->getType()->isVoidTy())
395    // Return result of the call.
396    ReturnInst::Create(F->getContext(), TheCall, StubBB);
397  else
398    ReturnInst::Create(F->getContext(), StubBB);           // Just return void.
399
400  // Finally, call our nullary stub function.
401  GenericValue Result = runFunction(Stub, std::vector<GenericValue>());
402  // Erase it, since no other function can have a reference to it.
403  Stub->eraseFromParent();
404  // And return the result.
405  return Result;
406}
407
408void JIT::RegisterJITEventListener(JITEventListener *L) {
409  if (!L)
410    return;
411  MutexGuard locked(lock);
412  EventListeners.push_back(L);
413}
414void JIT::UnregisterJITEventListener(JITEventListener *L) {
415  if (!L)
416    return;
417  MutexGuard locked(lock);
418  std::vector<JITEventListener*>::reverse_iterator I=
419      std::find(EventListeners.rbegin(), EventListeners.rend(), L);
420  if (I != EventListeners.rend()) {
421    std::swap(*I, EventListeners.back());
422    EventListeners.pop_back();
423  }
424}
425void JIT::NotifyFunctionEmitted(
426    const Function &F,
427    void *Code, size_t Size,
428    const JITEvent_EmittedFunctionDetails &Details) {
429  MutexGuard locked(lock);
430  for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) {
431    EventListeners[I]->NotifyFunctionEmitted(F, Code, Size, Details);
432  }
433}
434
435void JIT::NotifyFreeingMachineCode(void *OldPtr) {
436  MutexGuard locked(lock);
437  for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) {
438    EventListeners[I]->NotifyFreeingMachineCode(OldPtr);
439  }
440}
441
442/// runJITOnFunction - Run the FunctionPassManager full of
443/// just-in-time compilation passes on F, hopefully filling in
444/// GlobalAddress[F] with the address of F's machine code.
445///
446void JIT::runJITOnFunction(Function *F, MachineCodeInfo *MCI) {
447  MutexGuard locked(lock);
448
449  class MCIListener : public JITEventListener {
450    MachineCodeInfo *const MCI;
451   public:
452    MCIListener(MachineCodeInfo *mci) : MCI(mci) {}
453    void NotifyFunctionEmitted(const Function &, void *Code, size_t Size,
454                               const EmittedFunctionDetails &) override {
455      MCI->setAddress(Code);
456      MCI->setSize(Size);
457    }
458  };
459  MCIListener MCIL(MCI);
460  if (MCI)
461    RegisterJITEventListener(&MCIL);
462
463  runJITOnFunctionUnlocked(F);
464
465  if (MCI)
466    UnregisterJITEventListener(&MCIL);
467}
468
469void JIT::runJITOnFunctionUnlocked(Function *F) {
470  assert(!isAlreadyCodeGenerating && "Error: Recursive compilation detected!");
471
472  jitTheFunctionUnlocked(F);
473
474  // If the function referred to another function that had not yet been
475  // read from bitcode, and we are jitting non-lazily, emit it now.
476  while (!jitstate->getPendingFunctions().empty()) {
477    Function *PF = jitstate->getPendingFunctions().back();
478    jitstate->getPendingFunctions().pop_back();
479
480    assert(!PF->hasAvailableExternallyLinkage() &&
481           "Externally-defined function should not be in pending list.");
482
483    jitTheFunctionUnlocked(PF);
484
485    // Now that the function has been jitted, ask the JITEmitter to rewrite
486    // the stub with real address of the function.
487    updateFunctionStubUnlocked(PF);
488  }
489}
490
491void JIT::jitTheFunctionUnlocked(Function *F) {
492  isAlreadyCodeGenerating = true;
493  jitstate->getPM().run(*F);
494  isAlreadyCodeGenerating = false;
495
496  // clear basic block addresses after this function is done
497  getBasicBlockAddressMap().clear();
498}
499
500/// getPointerToFunction - This method is used to get the address of the
501/// specified function, compiling it if necessary.
502///
503void *JIT::getPointerToFunction(Function *F) {
504
505  if (void *Addr = getPointerToGlobalIfAvailable(F))
506    return Addr;   // Check if function already code gen'd
507
508  MutexGuard locked(lock);
509
510  // Now that this thread owns the lock, make sure we read in the function if it
511  // exists in this Module.
512  std::string ErrorMsg;
513  if (F->Materialize(&ErrorMsg)) {
514    report_fatal_error("Error reading function '" + F->getName()+
515                      "' from bitcode file: " + ErrorMsg);
516  }
517
518  // ... and check if another thread has already code gen'd the function.
519  if (void *Addr = getPointerToGlobalIfAvailable(F))
520    return Addr;
521
522  if (F->isDeclaration() || F->hasAvailableExternallyLinkage()) {
523    bool AbortOnFailure = !F->hasExternalWeakLinkage();
524    void *Addr = getPointerToNamedFunction(F->getName(), AbortOnFailure);
525    addGlobalMapping(F, Addr);
526    return Addr;
527  }
528
529  runJITOnFunctionUnlocked(F);
530
531  void *Addr = getPointerToGlobalIfAvailable(F);
532  assert(Addr && "Code generation didn't add function to GlobalAddress table!");
533  return Addr;
534}
535
536void JIT::addPointerToBasicBlock(const BasicBlock *BB, void *Addr) {
537  MutexGuard locked(lock);
538
539  BasicBlockAddressMapTy::iterator I =
540    getBasicBlockAddressMap().find(BB);
541  if (I == getBasicBlockAddressMap().end()) {
542    getBasicBlockAddressMap()[BB] = Addr;
543  } else {
544    // ignore repeats: some BBs can be split into few MBBs?
545  }
546}
547
548void JIT::clearPointerToBasicBlock(const BasicBlock *BB) {
549  MutexGuard locked(lock);
550  getBasicBlockAddressMap().erase(BB);
551}
552
553void *JIT::getPointerToBasicBlock(BasicBlock *BB) {
554  // make sure it's function is compiled by JIT
555  (void)getPointerToFunction(BB->getParent());
556
557  // resolve basic block address
558  MutexGuard locked(lock);
559
560  BasicBlockAddressMapTy::iterator I =
561    getBasicBlockAddressMap().find(BB);
562  if (I != getBasicBlockAddressMap().end()) {
563    return I->second;
564  } else {
565    llvm_unreachable("JIT does not have BB address for address-of-label, was"
566                     " it eliminated by optimizer?");
567  }
568}
569
570void *JIT::getPointerToNamedFunction(const std::string &Name,
571                                     bool AbortOnFailure){
572  if (!isSymbolSearchingDisabled()) {
573    void *ptr = JMM->getPointerToNamedFunction(Name, false);
574    if (ptr)
575      return ptr;
576  }
577
578  /// If a LazyFunctionCreator is installed, use it to get/create the function.
579  if (LazyFunctionCreator)
580    if (void *RP = LazyFunctionCreator(Name))
581      return RP;
582
583  if (AbortOnFailure) {
584    report_fatal_error("Program used external function '"+Name+
585                      "' which could not be resolved!");
586  }
587  return nullptr;
588}
589
590
591/// getOrEmitGlobalVariable - Return the address of the specified global
592/// variable, possibly emitting it to memory if needed.  This is used by the
593/// Emitter.
594void *JIT::getOrEmitGlobalVariable(const GlobalVariable *GV) {
595  MutexGuard locked(lock);
596
597  void *Ptr = getPointerToGlobalIfAvailable(GV);
598  if (Ptr) return Ptr;
599
600  // If the global is external, just remember the address.
601  if (GV->isDeclaration() || GV->hasAvailableExternallyLinkage()) {
602#if HAVE___DSO_HANDLE
603    if (GV->getName() == "__dso_handle")
604      return (void*)&__dso_handle;
605#endif
606    Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(GV->getName());
607    if (!Ptr) {
608      report_fatal_error("Could not resolve external global address: "
609                        +GV->getName());
610    }
611    addGlobalMapping(GV, Ptr);
612  } else {
613    // If the global hasn't been emitted to memory yet, allocate space and
614    // emit it into memory.
615    Ptr = getMemoryForGV(GV);
616    addGlobalMapping(GV, Ptr);
617    EmitGlobalVariable(GV);  // Initialize the variable.
618  }
619  return Ptr;
620}
621
622/// recompileAndRelinkFunction - This method is used to force a function
623/// which has already been compiled, to be compiled again, possibly
624/// after it has been modified. Then the entry to the old copy is overwritten
625/// with a branch to the new copy. If there was no old copy, this acts
626/// just like JIT::getPointerToFunction().
627///
628void *JIT::recompileAndRelinkFunction(Function *F) {
629  void *OldAddr = getPointerToGlobalIfAvailable(F);
630
631  // If it's not already compiled there is no reason to patch it up.
632  if (!OldAddr) return getPointerToFunction(F);
633
634  // Delete the old function mapping.
635  addGlobalMapping(F, nullptr);
636
637  // Recodegen the function
638  runJITOnFunction(F);
639
640  // Update state, forward the old function to the new function.
641  void *Addr = getPointerToGlobalIfAvailable(F);
642  assert(Addr && "Code generation didn't add function to GlobalAddress table!");
643  TJI.replaceMachineCodeForFunction(OldAddr, Addr);
644  return Addr;
645}
646
647/// getMemoryForGV - This method abstracts memory allocation of global
648/// variable so that the JIT can allocate thread local variables depending
649/// on the target.
650///
651char* JIT::getMemoryForGV(const GlobalVariable* GV) {
652  char *Ptr;
653
654  // GlobalVariable's which are not "constant" will cause trouble in a server
655  // situation. It's returned in the same block of memory as code which may
656  // not be writable.
657  if (isGVCompilationDisabled() && !GV->isConstant()) {
658    report_fatal_error("Compilation of non-internal GlobalValue is disabled!");
659  }
660
661  // Some applications require globals and code to live together, so they may
662  // be allocated into the same buffer, but in general globals are allocated
663  // through the memory manager which puts them near the code but not in the
664  // same buffer.
665  Type *GlobalType = GV->getType()->getElementType();
666  size_t S = getDataLayout()->getTypeAllocSize(GlobalType);
667  size_t A = getDataLayout()->getPreferredAlignment(GV);
668  if (GV->isThreadLocal()) {
669    MutexGuard locked(lock);
670    Ptr = TJI.allocateThreadLocalMemory(S);
671  } else if (TJI.allocateSeparateGVMemory()) {
672    if (A <= 8) {
673      Ptr = (char*)malloc(S);
674    } else {
675      // Allocate S+A bytes of memory, then use an aligned pointer within that
676      // space.
677      Ptr = (char*)malloc(S+A);
678      unsigned MisAligned = ((intptr_t)Ptr & (A-1));
679      Ptr = Ptr + (MisAligned ? (A-MisAligned) : 0);
680    }
681  } else if (AllocateGVsWithCode) {
682    Ptr = (char*)JCE->allocateSpace(S, A);
683  } else {
684    Ptr = (char*)JCE->allocateGlobal(S, A);
685  }
686  return Ptr;
687}
688
689void JIT::addPendingFunction(Function *F) {
690  MutexGuard locked(lock);
691  jitstate->getPendingFunctions().push_back(F);
692}
693
694
695JITEventListener::~JITEventListener() {}
696