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/ADT/SmallPtrSet.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/ErrorHandling.h"
31 #include "llvm/Support/ManagedStatic.h"
32 #include "llvm/Support/MutexGuard.h"
33 #include "llvm/System/DynamicLibrary.h"
34 #include "llvm/Config/config.h"
39 // Apple gcc defaults to -fuse-cxa-atexit (i.e. calls __cxa_atexit instead
40 // of atexit). It passes the address of linker generated symbol __dso_handle
42 // This configuration change happened at version 5330.
43 # include <AvailabilityMacros.h>
44 # if defined(MAC_OS_X_VERSION_10_4) && \
45 ((MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_4) || \
46 (MAC_OS_X_VERSION_MIN_REQUIRED == MAC_OS_X_VERSION_10_4 && \
47 __APPLE_CC__ >= 5330))
48 # ifndef HAVE___DSO_HANDLE
49 # define HAVE___DSO_HANDLE 1
55 extern void *__dso_handle __attribute__ ((__visibility__ ("hidden")));
60 static struct RegisterJIT {
61 RegisterJIT() { JIT::Register(); }
66 extern "C" void LLVMLinkInJIT() {
70 #if defined(__GNUC__) && !defined(__ARM__EABI__)
72 // libgcc defines the __register_frame function to dynamically register new
73 // dwarf frames for exception handling. This functionality is not portable
74 // across compilers and is only provided by GCC. We use the __register_frame
75 // function here so that code generated by the JIT cooperates with the unwinding
76 // runtime of libgcc. When JITting with exception handling enable, LLVM
77 // generates dwarf frames and registers it to libgcc with __register_frame.
79 // The __register_frame function works with Linux.
81 // Unfortunately, this functionality seems to be in libgcc after the unwinding
82 // library of libgcc for darwin was written. The code for darwin overwrites the
83 // value updated by __register_frame with a value fetched with "keymgr".
84 // "keymgr" is an obsolete functionality, which should be rewritten some day.
85 // In the meantime, since "keymgr" is on all libgccs shipped with apple-gcc, we
86 // need a workaround in LLVM which uses the "keymgr" to dynamically modify the
87 // values of an opaque key, used by libgcc to find dwarf tables.
89 extern "C" void __register_frame(void*);
91 #if defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED <= 1050
101 // LibgccObject - This is the structure defined in libgcc. There is no #include
102 // provided for this structure, so we also define it here. libgcc calls it
103 // "struct object". The structure is undocumented in libgcc.
104 struct LibgccObject {
109 /// frame - Pointer to the exception table.
112 /// encoding - The encoding of the object?
115 unsigned long sorted : 1;
116 unsigned long from_array : 1;
117 unsigned long mixed_encoding : 1;
118 unsigned long encoding : 8;
119 unsigned long count : 21;
124 /// fde_end - libgcc defines this field only if some macro is defined. We
125 /// include this field even if it may not there, to make libgcc happy.
128 /// next - At least we know it's a chained list!
129 struct LibgccObject *next;
132 // "kemgr" stuff. Apparently, all frame tables are stored there.
133 extern "C" void _keymgr_set_and_unlock_processwide_ptr(int, void *);
134 extern "C" void *_keymgr_get_and_lock_processwide_ptr(int);
135 #define KEYMGR_GCC3_DW2_OBJ_LIST 302 /* Dwarf2 object list */
137 /// LibgccObjectInfo - libgcc defines this struct as km_object_info. It
138 /// probably contains all dwarf tables that are loaded.
139 struct LibgccObjectInfo {
141 /// seenObjects - LibgccObjects already parsed by the unwinding runtime.
143 struct LibgccObject* seenObjects;
145 /// unseenObjects - LibgccObjects not parsed yet by the unwinding runtime.
147 struct LibgccObject* unseenObjects;
152 /// darwin_register_frame - Since __register_frame does not work with darwin's
153 /// libgcc,we provide our own function, which "tricks" libgcc by modifying the
154 /// "Dwarf2 object list" key.
155 void DarwinRegisterFrame(void* FrameBegin) {
157 LibgccObjectInfo* LOI = (struct LibgccObjectInfo*)
158 _keymgr_get_and_lock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST);
159 assert(LOI && "This should be preallocated by the runtime");
161 // Allocate a new LibgccObject to represent this frame. Deallocation of this
162 // object may be impossible: since darwin code in libgcc was written after
163 // the ability to dynamically register frames, things may crash if we
165 struct LibgccObject* ob = (struct LibgccObject*)
166 malloc(sizeof(struct LibgccObject));
168 // Do like libgcc for the values of the field.
169 ob->unused1 = (void *)-1;
172 ob->frame = FrameBegin;
174 ob->encoding.b.encoding = llvm::dwarf::DW_EH_PE_omit;
176 // Put the info on both places, as libgcc uses the first or the second
177 // field. Note that we rely on having two pointers here. If fde_end was a
178 // char, things would get complicated.
179 ob->fde_end = (char*)LOI->unseenObjects;
180 ob->next = LOI->unseenObjects;
182 // Update the key's unseenObjects list.
183 LOI->unseenObjects = ob;
185 // Finally update the "key". Apparently, libgcc requires it.
186 _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST,
195 /// createJIT - This is the factory method for creating a JIT for the current
196 /// machine, it does not fall back to the interpreter. This takes ownership
198 ExecutionEngine *ExecutionEngine::createJIT(Module *M,
199 std::string *ErrorStr,
200 JITMemoryManager *JMM,
201 CodeGenOpt::Level OptLevel,
203 CodeModel::Model CMM) {
204 // Use the defaults for extra parameters. Users can use EngineBuilder to
206 StringRef MArch = "";
208 SmallVector<std::string, 1> MAttrs;
209 return JIT::createJIT(M, ErrorStr, JMM, OptLevel, GVsWithCode, CMM,
210 MArch, MCPU, MAttrs);
213 ExecutionEngine *JIT::createJIT(Module *M,
214 std::string *ErrorStr,
215 JITMemoryManager *JMM,
216 CodeGenOpt::Level OptLevel,
218 CodeModel::Model CMM,
221 const SmallVectorImpl<std::string>& MAttrs) {
222 // Make sure we can resolve symbols in the program as well. The zero arg
223 // to the function tells DynamicLibrary to load the program, not a library.
224 if (sys::DynamicLibrary::LoadLibraryPermanently(0, ErrorStr))
227 // Pick a target either via -march or by guessing the native arch.
228 TargetMachine *TM = JIT::selectTarget(M, MArch, MCPU, MAttrs, ErrorStr);
229 if (!TM || (ErrorStr && ErrorStr->length() > 0)) return 0;
230 TM->setCodeModel(CMM);
232 // If the target supports JIT code generation, create a the JIT.
233 if (TargetJITInfo *TJ = TM->getJITInfo()) {
234 return new JIT(M, *TM, *TJ, JMM, OptLevel, GVsWithCode);
237 *ErrorStr = "target does not support JIT code generation";
243 /// This class supports the global getPointerToNamedFunction(), which allows
244 /// bugpoint or gdb users to search for a function by name without any context.
246 SmallPtrSet<JIT*, 1> JITs; // Optimize for process containing just 1 JIT.
247 mutable sys::Mutex Lock;
250 MutexGuard guard(Lock);
253 void Remove(JIT *jit) {
254 MutexGuard guard(Lock);
257 void *getPointerToNamedFunction(const char *Name) const {
258 MutexGuard guard(Lock);
259 assert(JITs.size() != 0 && "No Jit registered");
260 //search function in every instance of JIT
261 for (SmallPtrSet<JIT*, 1>::const_iterator Jit = JITs.begin(),
264 if (Function *F = (*Jit)->FindFunctionNamed(Name))
265 return (*Jit)->getPointerToFunction(F);
267 // The function is not available : fallback on the first created (will
268 // search in symbol of the current program/library)
269 return (*JITs.begin())->getPointerToNamedFunction(Name);
272 ManagedStatic<JitPool> AllJits;
275 // getPointerToNamedFunction - This function is used as a global wrapper to
276 // JIT::getPointerToNamedFunction for the purpose of resolving symbols when
277 // bugpoint is debugging the JIT. In that scenario, we are loading an .so and
278 // need to resolve function(s) that are being mis-codegenerated, so we need to
279 // resolve their addresses at runtime, and this is the way to do it.
280 void *getPointerToNamedFunction(const char *Name) {
281 return AllJits->getPointerToNamedFunction(Name);
285 JIT::JIT(Module *M, TargetMachine &tm, TargetJITInfo &tji,
286 JITMemoryManager *JMM, CodeGenOpt::Level OptLevel, bool GVsWithCode)
287 : ExecutionEngine(M), TM(tm), TJI(tji), AllocateGVsWithCode(GVsWithCode),
288 isAlreadyCodeGenerating(false) {
289 setTargetData(TM.getTargetData());
291 jitstate = new JITState(M);
294 JCE = createEmitter(*this, JMM, TM);
296 // Register in global list of all JITs.
300 MutexGuard locked(lock);
301 FunctionPassManager &PM = jitstate->getPM(locked);
302 PM.add(new TargetData(*TM.getTargetData()));
304 // Turn the machine code intermediate representation into bytes in memory that
306 if (TM.addPassesToEmitMachineCode(PM, *JCE, OptLevel)) {
307 report_fatal_error("Target does not support machine code emission!");
310 // Register routine for informing unwinding runtime about new EH frames
311 #if defined(__GNUC__) && !defined(__ARM_EABI__)
313 struct LibgccObjectInfo* LOI = (struct LibgccObjectInfo*)
314 _keymgr_get_and_lock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST);
316 // The key is created on demand, and libgcc creates it the first time an
317 // exception occurs. Since we need the key to register frames, we create
320 LOI = (LibgccObjectInfo*)calloc(sizeof(struct LibgccObjectInfo), 1);
321 _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST, LOI);
322 InstallExceptionTableRegister(DarwinRegisterFrame);
324 InstallExceptionTableRegister(__register_frame);
328 // Initialize passes.
329 PM.doInitialization();
333 AllJits->Remove(this);
339 /// addModule - Add a new Module to the JIT. If we previously removed the last
340 /// Module, we need re-initialize jitstate with a valid Module.
341 void JIT::addModule(Module *M) {
342 MutexGuard locked(lock);
344 if (Modules.empty()) {
345 assert(!jitstate && "jitstate should be NULL if Modules vector is empty!");
347 jitstate = new JITState(M);
349 FunctionPassManager &PM = jitstate->getPM(locked);
350 PM.add(new TargetData(*TM.getTargetData()));
352 // Turn the machine code intermediate representation into bytes in memory
353 // that may be executed.
354 if (TM.addPassesToEmitMachineCode(PM, *JCE, CodeGenOpt::Default)) {
355 report_fatal_error("Target does not support machine code emission!");
358 // Initialize passes.
359 PM.doInitialization();
362 ExecutionEngine::addModule(M);
365 /// removeModule - If we are removing the last Module, invalidate the jitstate
366 /// since the PassManager it contains references a released Module.
367 bool JIT::removeModule(Module *M) {
368 bool result = ExecutionEngine::removeModule(M);
370 MutexGuard locked(lock);
372 if (jitstate->getModule() == M) {
377 if (!jitstate && !Modules.empty()) {
378 jitstate = new JITState(Modules[0]);
380 FunctionPassManager &PM = jitstate->getPM(locked);
381 PM.add(new TargetData(*TM.getTargetData()));
383 // Turn the machine code intermediate representation into bytes in memory
384 // that may be executed.
385 if (TM.addPassesToEmitMachineCode(PM, *JCE, CodeGenOpt::Default)) {
386 report_fatal_error("Target does not support machine code emission!");
389 // Initialize passes.
390 PM.doInitialization();
395 /// run - Start execution with the specified function and arguments.
397 GenericValue JIT::runFunction(Function *F,
398 const std::vector<GenericValue> &ArgValues) {
399 assert(F && "Function *F was null at entry to run()");
401 void *FPtr = getPointerToFunction(F);
402 assert(FPtr && "Pointer to fn's code was null after getPointerToFunction");
403 const FunctionType *FTy = F->getFunctionType();
404 const Type *RetTy = FTy->getReturnType();
406 assert((FTy->getNumParams() == ArgValues.size() ||
407 (FTy->isVarArg() && FTy->getNumParams() <= ArgValues.size())) &&
408 "Wrong number of arguments passed into function!");
409 assert(FTy->getNumParams() == ArgValues.size() &&
410 "This doesn't support passing arguments through varargs (yet)!");
412 // Handle some common cases first. These cases correspond to common `main'
414 if (RetTy->isIntegerTy(32) || RetTy->isVoidTy()) {
415 switch (ArgValues.size()) {
417 if (FTy->getParamType(0)->isIntegerTy(32) &&
418 FTy->getParamType(1)->isPointerTy() &&
419 FTy->getParamType(2)->isPointerTy()) {
420 int (*PF)(int, char **, const char **) =
421 (int(*)(int, char **, const char **))(intptr_t)FPtr;
423 // Call the function.
425 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
426 (char **)GVTOP(ArgValues[1]),
427 (const char **)GVTOP(ArgValues[2])));
432 if (FTy->getParamType(0)->isIntegerTy(32) &&
433 FTy->getParamType(1)->isPointerTy()) {
434 int (*PF)(int, char **) = (int(*)(int, char **))(intptr_t)FPtr;
436 // Call the function.
438 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
439 (char **)GVTOP(ArgValues[1])));
444 if (FTy->getNumParams() == 1 &&
445 FTy->getParamType(0)->isIntegerTy(32)) {
447 int (*PF)(int) = (int(*)(int))(intptr_t)FPtr;
448 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue()));
455 // Handle cases where no arguments are passed first.
456 if (ArgValues.empty()) {
458 switch (RetTy->getTypeID()) {
459 default: llvm_unreachable("Unknown return type for function call!");
460 case Type::IntegerTyID: {
461 unsigned BitWidth = cast<IntegerType>(RetTy)->getBitWidth();
463 rv.IntVal = APInt(BitWidth, ((bool(*)())(intptr_t)FPtr)());
464 else if (BitWidth <= 8)
465 rv.IntVal = APInt(BitWidth, ((char(*)())(intptr_t)FPtr)());
466 else if (BitWidth <= 16)
467 rv.IntVal = APInt(BitWidth, ((short(*)())(intptr_t)FPtr)());
468 else if (BitWidth <= 32)
469 rv.IntVal = APInt(BitWidth, ((int(*)())(intptr_t)FPtr)());
470 else if (BitWidth <= 64)
471 rv.IntVal = APInt(BitWidth, ((int64_t(*)())(intptr_t)FPtr)());
473 llvm_unreachable("Integer types > 64 bits not supported");
477 rv.IntVal = APInt(32, ((int(*)())(intptr_t)FPtr)());
479 case Type::FloatTyID:
480 rv.FloatVal = ((float(*)())(intptr_t)FPtr)();
482 case Type::DoubleTyID:
483 rv.DoubleVal = ((double(*)())(intptr_t)FPtr)();
485 case Type::X86_FP80TyID:
486 case Type::FP128TyID:
487 case Type::PPC_FP128TyID:
488 llvm_unreachable("long double not supported yet");
490 case Type::PointerTyID:
491 return PTOGV(((void*(*)())(intptr_t)FPtr)());
495 // Okay, this is not one of our quick and easy cases. Because we don't have a
496 // full FFI, we have to codegen a nullary stub function that just calls the
497 // function we are interested in, passing in constants for all of the
498 // arguments. Make this function and return.
500 // First, create the function.
501 FunctionType *STy=FunctionType::get(RetTy, false);
502 Function *Stub = Function::Create(STy, Function::InternalLinkage, "",
505 // Insert a basic block.
506 BasicBlock *StubBB = BasicBlock::Create(F->getContext(), "", Stub);
508 // Convert all of the GenericValue arguments over to constants. Note that we
509 // currently don't support varargs.
510 SmallVector<Value*, 8> Args;
511 for (unsigned i = 0, e = ArgValues.size(); i != e; ++i) {
513 const Type *ArgTy = FTy->getParamType(i);
514 const GenericValue &AV = ArgValues[i];
515 switch (ArgTy->getTypeID()) {
516 default: llvm_unreachable("Unknown argument type for function call!");
517 case Type::IntegerTyID:
518 C = ConstantInt::get(F->getContext(), AV.IntVal);
520 case Type::FloatTyID:
521 C = ConstantFP::get(F->getContext(), APFloat(AV.FloatVal));
523 case Type::DoubleTyID:
524 C = ConstantFP::get(F->getContext(), APFloat(AV.DoubleVal));
526 case Type::PPC_FP128TyID:
527 case Type::X86_FP80TyID:
528 case Type::FP128TyID:
529 C = ConstantFP::get(F->getContext(), APFloat(AV.IntVal));
531 case Type::PointerTyID:
532 void *ArgPtr = GVTOP(AV);
533 if (sizeof(void*) == 4)
534 C = ConstantInt::get(Type::getInt32Ty(F->getContext()),
535 (int)(intptr_t)ArgPtr);
537 C = ConstantInt::get(Type::getInt64Ty(F->getContext()),
539 // Cast the integer to pointer
540 C = ConstantExpr::getIntToPtr(C, ArgTy);
546 CallInst *TheCall = CallInst::Create(F, Args.begin(), Args.end(),
548 TheCall->setCallingConv(F->getCallingConv());
549 TheCall->setTailCall();
550 if (!TheCall->getType()->isVoidTy())
551 // Return result of the call.
552 ReturnInst::Create(F->getContext(), TheCall, StubBB);
554 ReturnInst::Create(F->getContext(), StubBB); // Just return void.
556 // Finally, call our nullary stub function.
557 GenericValue Result = runFunction(Stub, std::vector<GenericValue>());
558 // Erase it, since no other function can have a reference to it.
559 Stub->eraseFromParent();
560 // And return the result.
564 void JIT::RegisterJITEventListener(JITEventListener *L) {
567 MutexGuard locked(lock);
568 EventListeners.push_back(L);
570 void JIT::UnregisterJITEventListener(JITEventListener *L) {
573 MutexGuard locked(lock);
574 std::vector<JITEventListener*>::reverse_iterator I=
575 std::find(EventListeners.rbegin(), EventListeners.rend(), L);
576 if (I != EventListeners.rend()) {
577 std::swap(*I, EventListeners.back());
578 EventListeners.pop_back();
581 void JIT::NotifyFunctionEmitted(
583 void *Code, size_t Size,
584 const JITEvent_EmittedFunctionDetails &Details) {
585 MutexGuard locked(lock);
586 for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) {
587 EventListeners[I]->NotifyFunctionEmitted(F, Code, Size, Details);
591 void JIT::NotifyFreeingMachineCode(void *OldPtr) {
592 MutexGuard locked(lock);
593 for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) {
594 EventListeners[I]->NotifyFreeingMachineCode(OldPtr);
598 /// runJITOnFunction - Run the FunctionPassManager full of
599 /// just-in-time compilation passes on F, hopefully filling in
600 /// GlobalAddress[F] with the address of F's machine code.
602 void JIT::runJITOnFunction(Function *F, MachineCodeInfo *MCI) {
603 MutexGuard locked(lock);
605 class MCIListener : public JITEventListener {
606 MachineCodeInfo *const MCI;
608 MCIListener(MachineCodeInfo *mci) : MCI(mci) {}
609 virtual void NotifyFunctionEmitted(const Function &,
610 void *Code, size_t Size,
611 const EmittedFunctionDetails &) {
612 MCI->setAddress(Code);
616 MCIListener MCIL(MCI);
618 RegisterJITEventListener(&MCIL);
620 runJITOnFunctionUnlocked(F, locked);
623 UnregisterJITEventListener(&MCIL);
626 void JIT::runJITOnFunctionUnlocked(Function *F, const MutexGuard &locked) {
627 assert(!isAlreadyCodeGenerating && "Error: Recursive compilation detected!");
629 jitTheFunction(F, locked);
631 // If the function referred to another function that had not yet been
632 // read from bitcode, and we are jitting non-lazily, emit it now.
633 while (!jitstate->getPendingFunctions(locked).empty()) {
634 Function *PF = jitstate->getPendingFunctions(locked).back();
635 jitstate->getPendingFunctions(locked).pop_back();
637 assert(!PF->hasAvailableExternallyLinkage() &&
638 "Externally-defined function should not be in pending list.");
640 jitTheFunction(PF, locked);
642 // Now that the function has been jitted, ask the JITEmitter to rewrite
643 // the stub with real address of the function.
644 updateFunctionStub(PF);
648 void JIT::jitTheFunction(Function *F, const MutexGuard &locked) {
649 isAlreadyCodeGenerating = true;
650 jitstate->getPM(locked).run(*F);
651 isAlreadyCodeGenerating = false;
653 // clear basic block addresses after this function is done
654 getBasicBlockAddressMap(locked).clear();
657 /// getPointerToFunction - This method is used to get the address of the
658 /// specified function, compiling it if neccesary.
660 void *JIT::getPointerToFunction(Function *F) {
662 if (void *Addr = getPointerToGlobalIfAvailable(F))
663 return Addr; // Check if function already code gen'd
665 MutexGuard locked(lock);
667 // Now that this thread owns the lock, make sure we read in the function if it
668 // exists in this Module.
669 std::string ErrorMsg;
670 if (F->Materialize(&ErrorMsg)) {
671 report_fatal_error("Error reading function '" + F->getName()+
672 "' from bitcode file: " + ErrorMsg);
675 // ... and check if another thread has already code gen'd the function.
676 if (void *Addr = getPointerToGlobalIfAvailable(F))
679 if (F->isDeclaration() || F->hasAvailableExternallyLinkage()) {
680 bool AbortOnFailure = !F->hasExternalWeakLinkage();
681 void *Addr = getPointerToNamedFunction(F->getName(), AbortOnFailure);
682 addGlobalMapping(F, Addr);
686 runJITOnFunctionUnlocked(F, locked);
688 void *Addr = getPointerToGlobalIfAvailable(F);
689 assert(Addr && "Code generation didn't add function to GlobalAddress table!");
693 void JIT::addPointerToBasicBlock(const BasicBlock *BB, void *Addr) {
694 MutexGuard locked(lock);
696 BasicBlockAddressMapTy::iterator I =
697 getBasicBlockAddressMap(locked).find(BB);
698 if (I == getBasicBlockAddressMap(locked).end()) {
699 getBasicBlockAddressMap(locked)[BB] = Addr;
701 // ignore repeats: some BBs can be split into few MBBs?
705 void JIT::clearPointerToBasicBlock(const BasicBlock *BB) {
706 MutexGuard locked(lock);
707 getBasicBlockAddressMap(locked).erase(BB);
710 void *JIT::getPointerToBasicBlock(BasicBlock *BB) {
711 // make sure it's function is compiled by JIT
712 (void)getPointerToFunction(BB->getParent());
714 // resolve basic block address
715 MutexGuard locked(lock);
717 BasicBlockAddressMapTy::iterator I =
718 getBasicBlockAddressMap(locked).find(BB);
719 if (I != getBasicBlockAddressMap(locked).end()) {
722 assert(0 && "JIT does not have BB address for address-of-label, was"
723 " it eliminated by optimizer?");
728 /// getOrEmitGlobalVariable - Return the address of the specified global
729 /// variable, possibly emitting it to memory if needed. This is used by the
731 void *JIT::getOrEmitGlobalVariable(const GlobalVariable *GV) {
732 MutexGuard locked(lock);
734 void *Ptr = getPointerToGlobalIfAvailable(GV);
737 // If the global is external, just remember the address.
738 if (GV->isDeclaration() || GV->hasAvailableExternallyLinkage()) {
739 #if HAVE___DSO_HANDLE
740 if (GV->getName() == "__dso_handle")
741 return (void*)&__dso_handle;
743 Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(GV->getName());
745 report_fatal_error("Could not resolve external global address: "
748 addGlobalMapping(GV, Ptr);
750 // If the global hasn't been emitted to memory yet, allocate space and
751 // emit it into memory.
752 Ptr = getMemoryForGV(GV);
753 addGlobalMapping(GV, Ptr);
754 EmitGlobalVariable(GV); // Initialize the variable.
759 /// recompileAndRelinkFunction - This method is used to force a function
760 /// which has already been compiled, to be compiled again, possibly
761 /// after it has been modified. Then the entry to the old copy is overwritten
762 /// with a branch to the new copy. If there was no old copy, this acts
763 /// just like JIT::getPointerToFunction().
765 void *JIT::recompileAndRelinkFunction(Function *F) {
766 void *OldAddr = getPointerToGlobalIfAvailable(F);
768 // If it's not already compiled there is no reason to patch it up.
769 if (OldAddr == 0) { return getPointerToFunction(F); }
771 // Delete the old function mapping.
772 addGlobalMapping(F, 0);
774 // Recodegen the function
777 // Update state, forward the old function to the new function.
778 void *Addr = getPointerToGlobalIfAvailable(F);
779 assert(Addr && "Code generation didn't add function to GlobalAddress table!");
780 TJI.replaceMachineCodeForFunction(OldAddr, Addr);
784 /// getMemoryForGV - This method abstracts memory allocation of global
785 /// variable so that the JIT can allocate thread local variables depending
788 char* JIT::getMemoryForGV(const GlobalVariable* GV) {
791 // GlobalVariable's which are not "constant" will cause trouble in a server
792 // situation. It's returned in the same block of memory as code which may
794 if (isGVCompilationDisabled() && !GV->isConstant()) {
795 report_fatal_error("Compilation of non-internal GlobalValue is disabled!");
798 // Some applications require globals and code to live together, so they may
799 // be allocated into the same buffer, but in general globals are allocated
800 // through the memory manager which puts them near the code but not in the
802 const Type *GlobalType = GV->getType()->getElementType();
803 size_t S = getTargetData()->getTypeAllocSize(GlobalType);
804 size_t A = getTargetData()->getPreferredAlignment(GV);
805 if (GV->isThreadLocal()) {
806 MutexGuard locked(lock);
807 Ptr = TJI.allocateThreadLocalMemory(S);
808 } else if (TJI.allocateSeparateGVMemory()) {
810 Ptr = (char*)malloc(S);
812 // Allocate S+A bytes of memory, then use an aligned pointer within that
814 Ptr = (char*)malloc(S+A);
815 unsigned MisAligned = ((intptr_t)Ptr & (A-1));
816 Ptr = Ptr + (MisAligned ? (A-MisAligned) : 0);
818 } else if (AllocateGVsWithCode) {
819 Ptr = (char*)JCE->allocateSpace(S, A);
821 Ptr = (char*)JCE->allocateGlobal(S, A);
826 void JIT::addPendingFunction(Function *F) {
827 MutexGuard locked(lock);
828 jitstate->getPendingFunctions(locked).push_back(F);
832 JITEventListener::~JITEventListener() {}