1 //===-- JIT.cpp - LLVM Just in Time Compiler ------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This tool implements a just-in-time compiler for LLVM, allowing direct
11 // execution of LLVM bitcode in an efficient manner.
13 //===----------------------------------------------------------------------===//
16 #include "llvm/Constants.h"
17 #include "llvm/DerivedTypes.h"
18 #include "llvm/Function.h"
19 #include "llvm/GlobalVariable.h"
20 #include "llvm/Instructions.h"
21 #include "llvm/ModuleProvider.h"
22 #include "llvm/CodeGen/JITCodeEmitter.h"
23 #include "llvm/CodeGen/MachineCodeInfo.h"
24 #include "llvm/ExecutionEngine/GenericValue.h"
25 #include "llvm/ExecutionEngine/JITEventListener.h"
26 #include "llvm/Target/TargetData.h"
27 #include "llvm/Target/TargetMachine.h"
28 #include "llvm/Target/TargetJITInfo.h"
29 #include "llvm/Support/Dwarf.h"
30 #include "llvm/Support/MutexGuard.h"
31 #include "llvm/System/DynamicLibrary.h"
32 #include "llvm/Config/config.h"
37 // Apple gcc defaults to -fuse-cxa-atexit (i.e. calls __cxa_atexit instead
38 // of atexit). It passes the address of linker generated symbol __dso_handle
40 // This configuration change happened at version 5330.
41 # include <AvailabilityMacros.h>
42 # if defined(MAC_OS_X_VERSION_10_4) && \
43 ((MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_4) || \
44 (MAC_OS_X_VERSION_MIN_REQUIRED == MAC_OS_X_VERSION_10_4 && \
45 __APPLE_CC__ >= 5330))
46 # ifndef HAVE___DSO_HANDLE
47 # define HAVE___DSO_HANDLE 1
53 extern void *__dso_handle __attribute__ ((__visibility__ ("hidden")));
58 static struct RegisterJIT {
59 RegisterJIT() { JIT::Register(); }
64 extern "C" void LLVMLinkInJIT() {
68 #if defined(__GNUC__) && !defined(__ARM__EABI__)
70 // libgcc defines the __register_frame function to dynamically register new
71 // dwarf frames for exception handling. This functionality is not portable
72 // across compilers and is only provided by GCC. We use the __register_frame
73 // function here so that code generated by the JIT cooperates with the unwinding
74 // runtime of libgcc. When JITting with exception handling enable, LLVM
75 // generates dwarf frames and registers it to libgcc with __register_frame.
77 // The __register_frame function works with Linux.
79 // Unfortunately, this functionality seems to be in libgcc after the unwinding
80 // library of libgcc for darwin was written. The code for darwin overwrites the
81 // value updated by __register_frame with a value fetched with "keymgr".
82 // "keymgr" is an obsolete functionality, which should be rewritten some day.
83 // In the meantime, since "keymgr" is on all libgccs shipped with apple-gcc, we
84 // need a workaround in LLVM which uses the "keymgr" to dynamically modify the
85 // values of an opaque key, used by libgcc to find dwarf tables.
87 extern "C" void __register_frame(void*);
89 #if defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED <= 1050
99 // LibgccObject - This is the structure defined in libgcc. There is no #include
100 // provided for this structure, so we also define it here. libgcc calls it
101 // "struct object". The structure is undocumented in libgcc.
102 struct LibgccObject {
107 /// frame - Pointer to the exception table.
110 /// encoding - The encoding of the object?
113 unsigned long sorted : 1;
114 unsigned long from_array : 1;
115 unsigned long mixed_encoding : 1;
116 unsigned long encoding : 8;
117 unsigned long count : 21;
122 /// fde_end - libgcc defines this field only if some macro is defined. We
123 /// include this field even if it may not there, to make libgcc happy.
126 /// next - At least we know it's a chained list!
127 struct LibgccObject *next;
130 // "kemgr" stuff. Apparently, all frame tables are stored there.
131 extern "C" void _keymgr_set_and_unlock_processwide_ptr(int, void *);
132 extern "C" void *_keymgr_get_and_lock_processwide_ptr(int);
133 #define KEYMGR_GCC3_DW2_OBJ_LIST 302 /* Dwarf2 object list */
135 /// LibgccObjectInfo - libgcc defines this struct as km_object_info. It
136 /// probably contains all dwarf tables that are loaded.
137 struct LibgccObjectInfo {
139 /// seenObjects - LibgccObjects already parsed by the unwinding runtime.
141 struct LibgccObject* seenObjects;
143 /// unseenObjects - LibgccObjects not parsed yet by the unwinding runtime.
145 struct LibgccObject* unseenObjects;
150 /// darwin_register_frame - Since __register_frame does not work with darwin's
151 /// libgcc,we provide our own function, which "tricks" libgcc by modifying the
152 /// "Dwarf2 object list" key.
153 void DarwinRegisterFrame(void* FrameBegin) {
155 LibgccObjectInfo* LOI = (struct LibgccObjectInfo*)
156 _keymgr_get_and_lock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST);
157 assert(LOI && "This should be preallocated by the runtime");
159 // Allocate a new LibgccObject to represent this frame. Deallocation of this
160 // object may be impossible: since darwin code in libgcc was written after
161 // the ability to dynamically register frames, things may crash if we
163 struct LibgccObject* ob = (struct LibgccObject*)
164 malloc(sizeof(struct LibgccObject));
166 // Do like libgcc for the values of the field.
167 ob->unused1 = (void *)-1;
170 ob->frame = FrameBegin;
172 ob->encoding.b.encoding = llvm::dwarf::DW_EH_PE_omit;
174 // Put the info on both places, as libgcc uses the first or the the second
175 // field. Note that we rely on having two pointers here. If fde_end was a
176 // char, things would get complicated.
177 ob->fde_end = (char*)LOI->unseenObjects;
178 ob->next = LOI->unseenObjects;
180 // Update the key's unseenObjects list.
181 LOI->unseenObjects = ob;
183 // Finally update the "key". Apparently, libgcc requires it.
184 _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST,
193 /// createJIT - This is the factory method for creating a JIT for the current
194 /// machine, it does not fall back to the interpreter. This takes ownership
195 /// of the module provider.
196 ExecutionEngine *ExecutionEngine::createJIT(ModuleProvider *MP,
197 std::string *ErrorStr,
198 JITMemoryManager *JMM,
199 CodeGenOpt::Level OptLevel) {
200 ExecutionEngine *EE = JIT::createJIT(MP, ErrorStr, JMM, OptLevel);
203 // Make sure we can resolve symbols in the program as well. The zero arg
204 // to the function tells DynamicLibrary to load the program, not a library.
205 sys::DynamicLibrary::LoadLibraryPermanently(0, ErrorStr);
209 JIT::JIT(ModuleProvider *MP, TargetMachine &tm, TargetJITInfo &tji,
210 JITMemoryManager *JMM, CodeGenOpt::Level OptLevel)
211 : ExecutionEngine(MP), TM(tm), TJI(tji) {
212 setTargetData(TM.getTargetData());
214 jitstate = new JITState(MP);
217 JCE = createEmitter(*this, JMM);
220 MutexGuard locked(lock);
221 FunctionPassManager &PM = jitstate->getPM(locked);
222 PM.add(new TargetData(*TM.getTargetData()));
224 // Turn the machine code intermediate representation into bytes in memory that
226 if (TM.addPassesToEmitMachineCode(PM, *JCE, OptLevel)) {
227 cerr << "Target does not support machine code emission!\n";
231 // Register routine for informing unwinding runtime about new EH frames
232 #if defined(__GNUC__) && !defined(__ARM_EABI__)
234 struct LibgccObjectInfo* LOI = (struct LibgccObjectInfo*)
235 _keymgr_get_and_lock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST);
237 // The key is created on demand, and libgcc creates it the first time an
238 // exception occurs. Since we need the key to register frames, we create
241 LOI = (LibgccObjectInfo*)calloc(sizeof(struct LibgccObjectInfo), 1);
242 _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST, LOI);
243 InstallExceptionTableRegister(DarwinRegisterFrame);
245 InstallExceptionTableRegister(__register_frame);
249 // Initialize passes.
250 PM.doInitialization();
259 /// addModuleProvider - Add a new ModuleProvider to the JIT. If we previously
260 /// removed the last ModuleProvider, we need re-initialize jitstate with a valid
262 void JIT::addModuleProvider(ModuleProvider *MP) {
263 MutexGuard locked(lock);
265 if (Modules.empty()) {
266 assert(!jitstate && "jitstate should be NULL if Modules vector is empty!");
268 jitstate = new JITState(MP);
270 FunctionPassManager &PM = jitstate->getPM(locked);
271 PM.add(new TargetData(*TM.getTargetData()));
273 // Turn the machine code intermediate representation into bytes in memory
274 // that may be executed.
275 if (TM.addPassesToEmitMachineCode(PM, *JCE, CodeGenOpt::Default)) {
276 cerr << "Target does not support machine code emission!\n";
280 // Initialize passes.
281 PM.doInitialization();
284 ExecutionEngine::addModuleProvider(MP);
287 /// removeModuleProvider - If we are removing the last ModuleProvider,
288 /// invalidate the jitstate since the PassManager it contains references a
289 /// released ModuleProvider.
290 Module *JIT::removeModuleProvider(ModuleProvider *MP, std::string *E) {
291 Module *result = ExecutionEngine::removeModuleProvider(MP, E);
293 MutexGuard locked(lock);
295 if (jitstate->getMP() == MP) {
300 if (!jitstate && !Modules.empty()) {
301 jitstate = new JITState(Modules[0]);
303 FunctionPassManager &PM = jitstate->getPM(locked);
304 PM.add(new TargetData(*TM.getTargetData()));
306 // Turn the machine code intermediate representation into bytes in memory
307 // that may be executed.
308 if (TM.addPassesToEmitMachineCode(PM, *JCE, CodeGenOpt::Default)) {
309 cerr << "Target does not support machine code emission!\n";
313 // Initialize passes.
314 PM.doInitialization();
319 /// deleteModuleProvider - Remove a ModuleProvider from the list of modules,
320 /// and deletes the ModuleProvider and owned Module. Avoids materializing
321 /// the underlying module.
322 void JIT::deleteModuleProvider(ModuleProvider *MP, std::string *E) {
323 ExecutionEngine::deleteModuleProvider(MP, E);
325 MutexGuard locked(lock);
327 if (jitstate->getMP() == MP) {
332 if (!jitstate && !Modules.empty()) {
333 jitstate = new JITState(Modules[0]);
335 FunctionPassManager &PM = jitstate->getPM(locked);
336 PM.add(new TargetData(*TM.getTargetData()));
338 // Turn the machine code intermediate representation into bytes in memory
339 // that may be executed.
340 if (TM.addPassesToEmitMachineCode(PM, *JCE, CodeGenOpt::Default)) {
341 cerr << "Target does not support machine code emission!\n";
345 // Initialize passes.
346 PM.doInitialization();
350 /// run - Start execution with the specified function and arguments.
352 GenericValue JIT::runFunction(Function *F,
353 const std::vector<GenericValue> &ArgValues) {
354 assert(F && "Function *F was null at entry to run()");
356 void *FPtr = getPointerToFunction(F);
357 assert(FPtr && "Pointer to fn's code was null after getPointerToFunction");
358 const FunctionType *FTy = F->getFunctionType();
359 const Type *RetTy = FTy->getReturnType();
361 assert((FTy->getNumParams() == ArgValues.size() ||
362 (FTy->isVarArg() && FTy->getNumParams() <= ArgValues.size())) &&
363 "Wrong number of arguments passed into function!");
364 assert(FTy->getNumParams() == ArgValues.size() &&
365 "This doesn't support passing arguments through varargs (yet)!");
367 // Handle some common cases first. These cases correspond to common `main'
369 if (RetTy == Type::Int32Ty || RetTy == Type::VoidTy) {
370 switch (ArgValues.size()) {
372 if (FTy->getParamType(0) == Type::Int32Ty &&
373 isa<PointerType>(FTy->getParamType(1)) &&
374 isa<PointerType>(FTy->getParamType(2))) {
375 int (*PF)(int, char **, const char **) =
376 (int(*)(int, char **, const char **))(intptr_t)FPtr;
378 // Call the function.
380 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
381 (char **)GVTOP(ArgValues[1]),
382 (const char **)GVTOP(ArgValues[2])));
387 if (FTy->getParamType(0) == Type::Int32Ty &&
388 isa<PointerType>(FTy->getParamType(1))) {
389 int (*PF)(int, char **) = (int(*)(int, char **))(intptr_t)FPtr;
391 // Call the function.
393 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
394 (char **)GVTOP(ArgValues[1])));
399 if (FTy->getNumParams() == 1 &&
400 FTy->getParamType(0) == Type::Int32Ty) {
402 int (*PF)(int) = (int(*)(int))(intptr_t)FPtr;
403 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue()));
410 // Handle cases where no arguments are passed first.
411 if (ArgValues.empty()) {
413 switch (RetTy->getTypeID()) {
414 default: assert(0 && "Unknown return type for function call!");
415 case Type::IntegerTyID: {
416 unsigned BitWidth = cast<IntegerType>(RetTy)->getBitWidth();
418 rv.IntVal = APInt(BitWidth, ((bool(*)())(intptr_t)FPtr)());
419 else if (BitWidth <= 8)
420 rv.IntVal = APInt(BitWidth, ((char(*)())(intptr_t)FPtr)());
421 else if (BitWidth <= 16)
422 rv.IntVal = APInt(BitWidth, ((short(*)())(intptr_t)FPtr)());
423 else if (BitWidth <= 32)
424 rv.IntVal = APInt(BitWidth, ((int(*)())(intptr_t)FPtr)());
425 else if (BitWidth <= 64)
426 rv.IntVal = APInt(BitWidth, ((int64_t(*)())(intptr_t)FPtr)());
428 assert(0 && "Integer types > 64 bits not supported");
432 rv.IntVal = APInt(32, ((int(*)())(intptr_t)FPtr)());
434 case Type::FloatTyID:
435 rv.FloatVal = ((float(*)())(intptr_t)FPtr)();
437 case Type::DoubleTyID:
438 rv.DoubleVal = ((double(*)())(intptr_t)FPtr)();
440 case Type::X86_FP80TyID:
441 case Type::FP128TyID:
442 case Type::PPC_FP128TyID:
443 assert(0 && "long double not supported yet");
445 case Type::PointerTyID:
446 return PTOGV(((void*(*)())(intptr_t)FPtr)());
450 // Okay, this is not one of our quick and easy cases. Because we don't have a
451 // full FFI, we have to codegen a nullary stub function that just calls the
452 // function we are interested in, passing in constants for all of the
453 // arguments. Make this function and return.
455 // First, create the function.
456 FunctionType *STy=FunctionType::get(RetTy, std::vector<const Type*>(), false);
457 Function *Stub = Function::Create(STy, Function::InternalLinkage, "",
460 // Insert a basic block.
461 BasicBlock *StubBB = BasicBlock::Create("", Stub);
463 // Convert all of the GenericValue arguments over to constants. Note that we
464 // currently don't support varargs.
465 SmallVector<Value*, 8> Args;
466 for (unsigned i = 0, e = ArgValues.size(); i != e; ++i) {
468 const Type *ArgTy = FTy->getParamType(i);
469 const GenericValue &AV = ArgValues[i];
470 switch (ArgTy->getTypeID()) {
471 default: assert(0 && "Unknown argument type for function call!");
472 case Type::IntegerTyID:
473 C = ConstantInt::get(AV.IntVal);
475 case Type::FloatTyID:
476 C = ConstantFP::get(APFloat(AV.FloatVal));
478 case Type::DoubleTyID:
479 C = ConstantFP::get(APFloat(AV.DoubleVal));
481 case Type::PPC_FP128TyID:
482 case Type::X86_FP80TyID:
483 case Type::FP128TyID:
484 C = ConstantFP::get(APFloat(AV.IntVal));
486 case Type::PointerTyID:
487 void *ArgPtr = GVTOP(AV);
488 if (sizeof(void*) == 4)
489 C = ConstantInt::get(Type::Int32Ty, (int)(intptr_t)ArgPtr);
491 C = ConstantInt::get(Type::Int64Ty, (intptr_t)ArgPtr);
492 C = ConstantExpr::getIntToPtr(C, ArgTy); // Cast the integer to pointer
498 CallInst *TheCall = CallInst::Create(F, Args.begin(), Args.end(),
500 TheCall->setCallingConv(F->getCallingConv());
501 TheCall->setTailCall();
502 if (TheCall->getType() != Type::VoidTy)
503 ReturnInst::Create(TheCall, StubBB); // Return result of the call.
505 ReturnInst::Create(StubBB); // Just return void.
507 // Finally, return the value returned by our nullary stub function.
508 return runFunction(Stub, std::vector<GenericValue>());
511 void JIT::RegisterJITEventListener(JITEventListener *L) {
514 MutexGuard locked(lock);
515 EventListeners.push_back(L);
517 void JIT::UnregisterJITEventListener(JITEventListener *L) {
520 MutexGuard locked(lock);
521 std::vector<JITEventListener*>::reverse_iterator I=
522 std::find(EventListeners.rbegin(), EventListeners.rend(), L);
523 if (I != EventListeners.rend()) {
524 std::swap(*I, EventListeners.back());
525 EventListeners.pop_back();
528 void JIT::NotifyFunctionEmitted(
530 void *Code, size_t Size,
531 const JITEvent_EmittedFunctionDetails &Details) {
532 MutexGuard locked(lock);
533 for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) {
534 EventListeners[I]->NotifyFunctionEmitted(F, Code, Size, Details);
538 void JIT::NotifyFreeingMachineCode(const Function &F, void *OldPtr) {
539 MutexGuard locked(lock);
540 for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) {
541 EventListeners[I]->NotifyFreeingMachineCode(F, OldPtr);
545 /// runJITOnFunction - Run the FunctionPassManager full of
546 /// just-in-time compilation passes on F, hopefully filling in
547 /// GlobalAddress[F] with the address of F's machine code.
549 void JIT::runJITOnFunction(Function *F, MachineCodeInfo *MCI) {
550 MutexGuard locked(lock);
552 class MCIListener : public JITEventListener {
553 MachineCodeInfo *const MCI;
555 MCIListener(MachineCodeInfo *mci) : MCI(mci) {}
556 virtual void NotifyFunctionEmitted(const Function &,
557 void *Code, size_t Size,
558 const EmittedFunctionDetails &) {
559 MCI->setAddress(Code);
563 MCIListener MCIL(MCI);
564 RegisterJITEventListener(&MCIL);
566 runJITOnFunctionUnlocked(F, locked);
568 UnregisterJITEventListener(&MCIL);
571 void JIT::runJITOnFunctionUnlocked(Function *F, const MutexGuard &locked) {
572 static bool isAlreadyCodeGenerating = false;
573 assert(!isAlreadyCodeGenerating && "Error: Recursive compilation detected!");
576 isAlreadyCodeGenerating = true;
577 jitstate->getPM(locked).run(*F);
578 isAlreadyCodeGenerating = false;
580 // If the function referred to another function that had not yet been
581 // read from bitcode, but we are jitting non-lazily, emit it now.
582 while (!jitstate->getPendingFunctions(locked).empty()) {
583 Function *PF = jitstate->getPendingFunctions(locked).back();
584 jitstate->getPendingFunctions(locked).pop_back();
587 isAlreadyCodeGenerating = true;
588 jitstate->getPM(locked).run(*PF);
589 isAlreadyCodeGenerating = false;
591 // Now that the function has been jitted, ask the JITEmitter to rewrite
592 // the stub with real address of the function.
593 updateFunctionStub(PF);
596 // If the JIT is configured to emit info so that dlsym can be used to
597 // rewrite stubs to external globals, do so now.
598 if (areDlsymStubsEnabled() && isLazyCompilationDisabled())
599 updateDlsymStubTable();
602 /// getPointerToFunction - This method is used to get the address of the
603 /// specified function, compiling it if neccesary.
605 void *JIT::getPointerToFunction(Function *F) {
607 if (void *Addr = getPointerToGlobalIfAvailable(F))
608 return Addr; // Check if function already code gen'd
610 MutexGuard locked(lock);
612 // Now that this thread owns the lock, check if another thread has already
613 // code gen'd the function.
614 if (void *Addr = getPointerToGlobalIfAvailable(F))
617 // Make sure we read in the function if it exists in this Module.
618 if (F->hasNotBeenReadFromBitcode()) {
619 // Determine the module provider this function is provided by.
620 Module *M = F->getParent();
621 ModuleProvider *MP = 0;
622 for (unsigned i = 0, e = Modules.size(); i != e; ++i) {
623 if (Modules[i]->getModule() == M) {
628 assert(MP && "Function isn't in a module we know about!");
630 std::string ErrorMsg;
631 if (MP->materializeFunction(F, &ErrorMsg)) {
632 cerr << "Error reading function '" << F->getName()
633 << "' from bitcode file: " << ErrorMsg << "\n";
637 // Now retry to get the address.
638 if (void *Addr = getPointerToGlobalIfAvailable(F))
642 if (F->isDeclaration()) {
643 bool AbortOnFailure =
644 !areDlsymStubsEnabled() && !F->hasExternalWeakLinkage();
645 void *Addr = getPointerToNamedFunction(F->getName(), AbortOnFailure);
646 addGlobalMapping(F, Addr);
650 runJITOnFunctionUnlocked(F, locked);
652 void *Addr = getPointerToGlobalIfAvailable(F);
653 assert(Addr && "Code generation didn't add function to GlobalAddress table!");
657 /// getOrEmitGlobalVariable - Return the address of the specified global
658 /// variable, possibly emitting it to memory if needed. This is used by the
660 void *JIT::getOrEmitGlobalVariable(const GlobalVariable *GV) {
661 MutexGuard locked(lock);
663 void *Ptr = getPointerToGlobalIfAvailable(GV);
666 // If the global is external, just remember the address.
667 if (GV->isDeclaration()) {
668 #if HAVE___DSO_HANDLE
669 if (GV->getName() == "__dso_handle")
670 return (void*)&__dso_handle;
672 Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(GV->getName().c_str());
673 if (Ptr == 0 && !areDlsymStubsEnabled()) {
674 cerr << "Could not resolve external global address: "
675 << GV->getName() << "\n";
678 addGlobalMapping(GV, Ptr);
680 // GlobalVariable's which are not "constant" will cause trouble in a server
681 // situation. It's returned in the same block of memory as code which may
683 if (isGVCompilationDisabled() && !GV->isConstant()) {
684 cerr << "Compilation of non-internal GlobalValue is disabled!\n";
687 // If the global hasn't been emitted to memory yet, allocate space and
688 // emit it into memory. It goes in the same array as the generated
689 // code, jump tables, etc.
690 const Type *GlobalType = GV->getType()->getElementType();
691 size_t S = getTargetData()->getTypeAllocSize(GlobalType);
692 size_t A = getTargetData()->getPreferredAlignment(GV);
693 if (GV->isThreadLocal()) {
694 MutexGuard locked(lock);
695 Ptr = TJI.allocateThreadLocalMemory(S);
696 } else if (TJI.allocateSeparateGVMemory()) {
700 // Allocate S+A bytes of memory, then use an aligned pointer within that
703 unsigned MisAligned = ((intptr_t)Ptr & (A-1));
704 Ptr = (char*)Ptr + (MisAligned ? (A-MisAligned) : 0);
707 Ptr = JCE->allocateSpace(S, A);
709 addGlobalMapping(GV, Ptr);
710 EmitGlobalVariable(GV);
715 /// recompileAndRelinkFunction - This method is used to force a function
716 /// which has already been compiled, to be compiled again, possibly
717 /// after it has been modified. Then the entry to the old copy is overwritten
718 /// with a branch to the new copy. If there was no old copy, this acts
719 /// just like JIT::getPointerToFunction().
721 void *JIT::recompileAndRelinkFunction(Function *F) {
722 void *OldAddr = getPointerToGlobalIfAvailable(F);
724 // If it's not already compiled there is no reason to patch it up.
725 if (OldAddr == 0) { return getPointerToFunction(F); }
727 // Delete the old function mapping.
728 addGlobalMapping(F, 0);
730 // Recodegen the function
733 // Update state, forward the old function to the new function.
734 void *Addr = getPointerToGlobalIfAvailable(F);
735 assert(Addr && "Code generation didn't add function to GlobalAddress table!");
736 TJI.replaceMachineCodeForFunction(OldAddr, Addr);
740 /// getMemoryForGV - This method abstracts memory allocation of global
741 /// variable so that the JIT can allocate thread local variables depending
744 char* JIT::getMemoryForGV(const GlobalVariable* GV) {
745 const Type *ElTy = GV->getType()->getElementType();
746 size_t GVSize = (size_t)getTargetData()->getTypeAllocSize(ElTy);
747 if (GV->isThreadLocal()) {
748 MutexGuard locked(lock);
749 return TJI.allocateThreadLocalMemory(GVSize);
751 return new char[GVSize];
755 void JIT::addPendingFunction(Function *F) {
756 MutexGuard locked(lock);
757 jitstate->getPendingFunctions(locked).push_back(F);
761 JITEventListener::~JITEventListener() {}