Silence -Wunused-variable in release builds.
[llvm/stm8.git] / lib / ExecutionEngine / JIT / JIT.cpp
blob8fceaf2b4931cb1fd889024462ea3df5a4d1d4b6
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.
13 //===----------------------------------------------------------------------===//
15 #include "JIT.h"
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/Support/DynamicLibrary.h"
34 #include "llvm/Config/config.h"
36 using namespace llvm;
38 #ifdef __APPLE__
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
41 // to the function.
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
50 # endif
51 # endif
52 #endif
54 #if HAVE___DSO_HANDLE
55 extern void *__dso_handle __attribute__ ((__visibility__ ("hidden")));
56 #endif
58 namespace {
60 static struct RegisterJIT {
61 RegisterJIT() { JIT::Register(); }
62 } JITRegistrator;
66 extern "C" void LLVMLinkInJIT() {
69 // Determine whether we can register EH tables.
70 #if (defined(__GNUC__) && !defined(__ARM_EABI__) && \
71 !defined(__USING_SJLJ_EXCEPTIONS__))
72 #define HAVE_EHTABLE_SUPPORT 1
73 #else
74 #define HAVE_EHTABLE_SUPPORT 0
75 #endif
77 #if HAVE_EHTABLE_SUPPORT
79 // libgcc defines the __register_frame function to dynamically register new
80 // dwarf frames for exception handling. This functionality is not portable
81 // across compilers and is only provided by GCC. We use the __register_frame
82 // function here so that code generated by the JIT cooperates with the unwinding
83 // runtime of libgcc. When JITting with exception handling enable, LLVM
84 // generates dwarf frames and registers it to libgcc with __register_frame.
86 // The __register_frame function works with Linux.
88 // Unfortunately, this functionality seems to be in libgcc after the unwinding
89 // library of libgcc for darwin was written. The code for darwin overwrites the
90 // value updated by __register_frame with a value fetched with "keymgr".
91 // "keymgr" is an obsolete functionality, which should be rewritten some day.
92 // In the meantime, since "keymgr" is on all libgccs shipped with apple-gcc, we
93 // need a workaround in LLVM which uses the "keymgr" to dynamically modify the
94 // values of an opaque key, used by libgcc to find dwarf tables.
96 extern "C" void __register_frame(void*);
97 extern "C" void __deregister_frame(void*);
99 #if defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED <= 1050
100 # define USE_KEYMGR 1
101 #else
102 # define USE_KEYMGR 0
103 #endif
105 #if USE_KEYMGR
107 namespace {
109 // LibgccObject - This is the structure defined in libgcc. There is no #include
110 // provided for this structure, so we also define it here. libgcc calls it
111 // "struct object". The structure is undocumented in libgcc.
112 struct LibgccObject {
113 void *unused1;
114 void *unused2;
115 void *unused3;
117 /// frame - Pointer to the exception table.
118 void *frame;
120 /// encoding - The encoding of the object?
121 union {
122 struct {
123 unsigned long sorted : 1;
124 unsigned long from_array : 1;
125 unsigned long mixed_encoding : 1;
126 unsigned long encoding : 8;
127 unsigned long count : 21;
128 } b;
129 size_t i;
130 } encoding;
132 /// fde_end - libgcc defines this field only if some macro is defined. We
133 /// include this field even if it may not there, to make libgcc happy.
134 char *fde_end;
136 /// next - At least we know it's a chained list!
137 struct LibgccObject *next;
140 // "kemgr" stuff. Apparently, all frame tables are stored there.
141 extern "C" void _keymgr_set_and_unlock_processwide_ptr(int, void *);
142 extern "C" void *_keymgr_get_and_lock_processwide_ptr(int);
143 #define KEYMGR_GCC3_DW2_OBJ_LIST 302 /* Dwarf2 object list */
145 /// LibgccObjectInfo - libgcc defines this struct as km_object_info. It
146 /// probably contains all dwarf tables that are loaded.
147 struct LibgccObjectInfo {
149 /// seenObjects - LibgccObjects already parsed by the unwinding runtime.
151 struct LibgccObject* seenObjects;
153 /// unseenObjects - LibgccObjects not parsed yet by the unwinding runtime.
155 struct LibgccObject* unseenObjects;
157 unsigned unused[2];
160 /// darwin_register_frame - Since __register_frame does not work with darwin's
161 /// libgcc,we provide our own function, which "tricks" libgcc by modifying the
162 /// "Dwarf2 object list" key.
163 void DarwinRegisterFrame(void* FrameBegin) {
164 // Get the key.
165 LibgccObjectInfo* LOI = (struct LibgccObjectInfo*)
166 _keymgr_get_and_lock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST);
167 assert(LOI && "This should be preallocated by the runtime");
169 // Allocate a new LibgccObject to represent this frame. Deallocation of this
170 // object may be impossible: since darwin code in libgcc was written after
171 // the ability to dynamically register frames, things may crash if we
172 // deallocate it.
173 struct LibgccObject* ob = (struct LibgccObject*)
174 malloc(sizeof(struct LibgccObject));
176 // Do like libgcc for the values of the field.
177 ob->unused1 = (void *)-1;
178 ob->unused2 = 0;
179 ob->unused3 = 0;
180 ob->frame = FrameBegin;
181 ob->encoding.i = 0;
182 ob->encoding.b.encoding = llvm::dwarf::DW_EH_PE_omit;
184 // Put the info on both places, as libgcc uses the first or the second
185 // field. Note that we rely on having two pointers here. If fde_end was a
186 // char, things would get complicated.
187 ob->fde_end = (char*)LOI->unseenObjects;
188 ob->next = LOI->unseenObjects;
190 // Update the key's unseenObjects list.
191 LOI->unseenObjects = ob;
193 // Finally update the "key". Apparently, libgcc requires it.
194 _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST,
195 LOI);
200 #endif // __APPLE__
201 #endif // HAVE_EHTABLE_SUPPORT
203 /// createJIT - This is the factory method for creating a JIT for the current
204 /// machine, it does not fall back to the interpreter. This takes ownership
205 /// of the module.
206 ExecutionEngine *JIT::createJIT(Module *M,
207 std::string *ErrorStr,
208 JITMemoryManager *JMM,
209 CodeGenOpt::Level OptLevel,
210 bool GVsWithCode,
211 TargetMachine *TM) {
212 // Try to register the program as a source of symbols to resolve against.
214 // FIXME: Don't do this here.
215 sys::DynamicLibrary::LoadLibraryPermanently(0, NULL);
217 // If the target supports JIT code generation, create the JIT.
218 if (TargetJITInfo *TJ = TM->getJITInfo()) {
219 return new JIT(M, *TM, *TJ, JMM, OptLevel, GVsWithCode);
220 } else {
221 if (ErrorStr)
222 *ErrorStr = "target does not support JIT code generation";
223 return 0;
227 namespace {
228 /// This class supports the global getPointerToNamedFunction(), which allows
229 /// bugpoint or gdb users to search for a function by name without any context.
230 class JitPool {
231 SmallPtrSet<JIT*, 1> JITs; // Optimize for process containing just 1 JIT.
232 mutable sys::Mutex Lock;
233 public:
234 void Add(JIT *jit) {
235 MutexGuard guard(Lock);
236 JITs.insert(jit);
238 void Remove(JIT *jit) {
239 MutexGuard guard(Lock);
240 JITs.erase(jit);
242 void *getPointerToNamedFunction(const char *Name) const {
243 MutexGuard guard(Lock);
244 assert(JITs.size() != 0 && "No Jit registered");
245 //search function in every instance of JIT
246 for (SmallPtrSet<JIT*, 1>::const_iterator Jit = JITs.begin(),
247 end = JITs.end();
248 Jit != end; ++Jit) {
249 if (Function *F = (*Jit)->FindFunctionNamed(Name))
250 return (*Jit)->getPointerToFunction(F);
252 // The function is not available : fallback on the first created (will
253 // search in symbol of the current program/library)
254 return (*JITs.begin())->getPointerToNamedFunction(Name);
257 ManagedStatic<JitPool> AllJits;
259 extern "C" {
260 // getPointerToNamedFunction - This function is used as a global wrapper to
261 // JIT::getPointerToNamedFunction for the purpose of resolving symbols when
262 // bugpoint is debugging the JIT. In that scenario, we are loading an .so and
263 // need to resolve function(s) that are being mis-codegenerated, so we need to
264 // resolve their addresses at runtime, and this is the way to do it.
265 void *getPointerToNamedFunction(const char *Name) {
266 return AllJits->getPointerToNamedFunction(Name);
270 JIT::JIT(Module *M, TargetMachine &tm, TargetJITInfo &tji,
271 JITMemoryManager *JMM, CodeGenOpt::Level OptLevel, bool GVsWithCode)
272 : ExecutionEngine(M), TM(tm), TJI(tji), AllocateGVsWithCode(GVsWithCode),
273 isAlreadyCodeGenerating(false) {
274 setTargetData(TM.getTargetData());
276 jitstate = new JITState(M);
278 // Initialize JCE
279 JCE = createEmitter(*this, JMM, TM);
281 // Register in global list of all JITs.
282 AllJits->Add(this);
284 // Add target data
285 MutexGuard locked(lock);
286 FunctionPassManager &PM = jitstate->getPM(locked);
287 PM.add(new TargetData(*TM.getTargetData()));
289 // Turn the machine code intermediate representation into bytes in memory that
290 // may be executed.
291 if (TM.addPassesToEmitMachineCode(PM, *JCE, OptLevel)) {
292 report_fatal_error("Target does not support machine code emission!");
295 // Register routine for informing unwinding runtime about new EH frames
296 #if HAVE_EHTABLE_SUPPORT
297 #if USE_KEYMGR
298 struct LibgccObjectInfo* LOI = (struct LibgccObjectInfo*)
299 _keymgr_get_and_lock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST);
301 // The key is created on demand, and libgcc creates it the first time an
302 // exception occurs. Since we need the key to register frames, we create
303 // it now.
304 if (!LOI)
305 LOI = (LibgccObjectInfo*)calloc(sizeof(struct LibgccObjectInfo), 1);
306 _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST, LOI);
307 InstallExceptionTableRegister(DarwinRegisterFrame);
308 // Not sure about how to deregister on Darwin.
309 #else
310 InstallExceptionTableRegister(__register_frame);
311 InstallExceptionTableDeregister(__deregister_frame);
312 #endif // __APPLE__
313 #endif // HAVE_EHTABLE_SUPPORT
315 // Initialize passes.
316 PM.doInitialization();
319 JIT::~JIT() {
320 // Unregister all exception tables registered by this JIT.
321 DeregisterAllTables();
322 // Cleanup.
323 AllJits->Remove(this);
324 delete jitstate;
325 delete JCE;
326 delete &TM;
329 /// addModule - Add a new Module to the JIT. If we previously removed the last
330 /// Module, we need re-initialize jitstate with a valid Module.
331 void JIT::addModule(Module *M) {
332 MutexGuard locked(lock);
334 if (Modules.empty()) {
335 assert(!jitstate && "jitstate should be NULL if Modules vector is empty!");
337 jitstate = new JITState(M);
339 FunctionPassManager &PM = jitstate->getPM(locked);
340 PM.add(new TargetData(*TM.getTargetData()));
342 // Turn the machine code intermediate representation into bytes in memory
343 // that may be executed.
344 if (TM.addPassesToEmitMachineCode(PM, *JCE, CodeGenOpt::Default)) {
345 report_fatal_error("Target does not support machine code emission!");
348 // Initialize passes.
349 PM.doInitialization();
352 ExecutionEngine::addModule(M);
355 /// removeModule - If we are removing the last Module, invalidate the jitstate
356 /// since the PassManager it contains references a released Module.
357 bool JIT::removeModule(Module *M) {
358 bool result = ExecutionEngine::removeModule(M);
360 MutexGuard locked(lock);
362 if (jitstate->getModule() == M) {
363 delete jitstate;
364 jitstate = 0;
367 if (!jitstate && !Modules.empty()) {
368 jitstate = new JITState(Modules[0]);
370 FunctionPassManager &PM = jitstate->getPM(locked);
371 PM.add(new TargetData(*TM.getTargetData()));
373 // Turn the machine code intermediate representation into bytes in memory
374 // that may be executed.
375 if (TM.addPassesToEmitMachineCode(PM, *JCE, CodeGenOpt::Default)) {
376 report_fatal_error("Target does not support machine code emission!");
379 // Initialize passes.
380 PM.doInitialization();
382 return result;
385 /// run - Start execution with the specified function and arguments.
387 GenericValue JIT::runFunction(Function *F,
388 const std::vector<GenericValue> &ArgValues) {
389 assert(F && "Function *F was null at entry to run()");
391 void *FPtr = getPointerToFunction(F);
392 assert(FPtr && "Pointer to fn's code was null after getPointerToFunction");
393 const FunctionType *FTy = F->getFunctionType();
394 const Type *RetTy = FTy->getReturnType();
396 assert((FTy->getNumParams() == ArgValues.size() ||
397 (FTy->isVarArg() && FTy->getNumParams() <= ArgValues.size())) &&
398 "Wrong number of arguments passed into function!");
399 assert(FTy->getNumParams() == ArgValues.size() &&
400 "This doesn't support passing arguments through varargs (yet)!");
402 // Handle some common cases first. These cases correspond to common `main'
403 // prototypes.
404 if (RetTy->isIntegerTy(32) || RetTy->isVoidTy()) {
405 switch (ArgValues.size()) {
406 case 3:
407 if (FTy->getParamType(0)->isIntegerTy(32) &&
408 FTy->getParamType(1)->isPointerTy() &&
409 FTy->getParamType(2)->isPointerTy()) {
410 int (*PF)(int, char **, const char **) =
411 (int(*)(int, char **, const char **))(intptr_t)FPtr;
413 // Call the function.
414 GenericValue rv;
415 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
416 (char **)GVTOP(ArgValues[1]),
417 (const char **)GVTOP(ArgValues[2])));
418 return rv;
420 break;
421 case 2:
422 if (FTy->getParamType(0)->isIntegerTy(32) &&
423 FTy->getParamType(1)->isPointerTy()) {
424 int (*PF)(int, char **) = (int(*)(int, char **))(intptr_t)FPtr;
426 // Call the function.
427 GenericValue rv;
428 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
429 (char **)GVTOP(ArgValues[1])));
430 return rv;
432 break;
433 case 1:
434 if (FTy->getNumParams() == 1 &&
435 FTy->getParamType(0)->isIntegerTy(32)) {
436 GenericValue rv;
437 int (*PF)(int) = (int(*)(int))(intptr_t)FPtr;
438 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue()));
439 return rv;
441 break;
445 // Handle cases where no arguments are passed first.
446 if (ArgValues.empty()) {
447 GenericValue rv;
448 switch (RetTy->getTypeID()) {
449 default: llvm_unreachable("Unknown return type for function call!");
450 case Type::IntegerTyID: {
451 unsigned BitWidth = cast<IntegerType>(RetTy)->getBitWidth();
452 if (BitWidth == 1)
453 rv.IntVal = APInt(BitWidth, ((bool(*)())(intptr_t)FPtr)());
454 else if (BitWidth <= 8)
455 rv.IntVal = APInt(BitWidth, ((char(*)())(intptr_t)FPtr)());
456 else if (BitWidth <= 16)
457 rv.IntVal = APInt(BitWidth, ((short(*)())(intptr_t)FPtr)());
458 else if (BitWidth <= 32)
459 rv.IntVal = APInt(BitWidth, ((int(*)())(intptr_t)FPtr)());
460 else if (BitWidth <= 64)
461 rv.IntVal = APInt(BitWidth, ((int64_t(*)())(intptr_t)FPtr)());
462 else
463 llvm_unreachable("Integer types > 64 bits not supported");
464 return rv;
466 case Type::VoidTyID:
467 rv.IntVal = APInt(32, ((int(*)())(intptr_t)FPtr)());
468 return rv;
469 case Type::FloatTyID:
470 rv.FloatVal = ((float(*)())(intptr_t)FPtr)();
471 return rv;
472 case Type::DoubleTyID:
473 rv.DoubleVal = ((double(*)())(intptr_t)FPtr)();
474 return rv;
475 case Type::X86_FP80TyID:
476 case Type::FP128TyID:
477 case Type::PPC_FP128TyID:
478 llvm_unreachable("long double not supported yet");
479 return rv;
480 case Type::PointerTyID:
481 return PTOGV(((void*(*)())(intptr_t)FPtr)());
485 // Okay, this is not one of our quick and easy cases. Because we don't have a
486 // full FFI, we have to codegen a nullary stub function that just calls the
487 // function we are interested in, passing in constants for all of the
488 // arguments. Make this function and return.
490 // First, create the function.
491 FunctionType *STy=FunctionType::get(RetTy, false);
492 Function *Stub = Function::Create(STy, Function::InternalLinkage, "",
493 F->getParent());
495 // Insert a basic block.
496 BasicBlock *StubBB = BasicBlock::Create(F->getContext(), "", Stub);
498 // Convert all of the GenericValue arguments over to constants. Note that we
499 // currently don't support varargs.
500 SmallVector<Value*, 8> Args;
501 for (unsigned i = 0, e = ArgValues.size(); i != e; ++i) {
502 Constant *C = 0;
503 const Type *ArgTy = FTy->getParamType(i);
504 const GenericValue &AV = ArgValues[i];
505 switch (ArgTy->getTypeID()) {
506 default: llvm_unreachable("Unknown argument type for function call!");
507 case Type::IntegerTyID:
508 C = ConstantInt::get(F->getContext(), AV.IntVal);
509 break;
510 case Type::FloatTyID:
511 C = ConstantFP::get(F->getContext(), APFloat(AV.FloatVal));
512 break;
513 case Type::DoubleTyID:
514 C = ConstantFP::get(F->getContext(), APFloat(AV.DoubleVal));
515 break;
516 case Type::PPC_FP128TyID:
517 case Type::X86_FP80TyID:
518 case Type::FP128TyID:
519 C = ConstantFP::get(F->getContext(), APFloat(AV.IntVal));
520 break;
521 case Type::PointerTyID:
522 void *ArgPtr = GVTOP(AV);
523 if (sizeof(void*) == 4)
524 C = ConstantInt::get(Type::getInt32Ty(F->getContext()),
525 (int)(intptr_t)ArgPtr);
526 else
527 C = ConstantInt::get(Type::getInt64Ty(F->getContext()),
528 (intptr_t)ArgPtr);
529 // Cast the integer to pointer
530 C = ConstantExpr::getIntToPtr(C, ArgTy);
531 break;
533 Args.push_back(C);
536 CallInst *TheCall = CallInst::Create(F, Args.begin(), Args.end(),
537 "", StubBB);
538 TheCall->setCallingConv(F->getCallingConv());
539 TheCall->setTailCall();
540 if (!TheCall->getType()->isVoidTy())
541 // Return result of the call.
542 ReturnInst::Create(F->getContext(), TheCall, StubBB);
543 else
544 ReturnInst::Create(F->getContext(), StubBB); // Just return void.
546 // Finally, call our nullary stub function.
547 GenericValue Result = runFunction(Stub, std::vector<GenericValue>());
548 // Erase it, since no other function can have a reference to it.
549 Stub->eraseFromParent();
550 // And return the result.
551 return Result;
554 void JIT::RegisterJITEventListener(JITEventListener *L) {
555 if (L == NULL)
556 return;
557 MutexGuard locked(lock);
558 EventListeners.push_back(L);
560 void JIT::UnregisterJITEventListener(JITEventListener *L) {
561 if (L == NULL)
562 return;
563 MutexGuard locked(lock);
564 std::vector<JITEventListener*>::reverse_iterator I=
565 std::find(EventListeners.rbegin(), EventListeners.rend(), L);
566 if (I != EventListeners.rend()) {
567 std::swap(*I, EventListeners.back());
568 EventListeners.pop_back();
571 void JIT::NotifyFunctionEmitted(
572 const Function &F,
573 void *Code, size_t Size,
574 const JITEvent_EmittedFunctionDetails &Details) {
575 MutexGuard locked(lock);
576 for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) {
577 EventListeners[I]->NotifyFunctionEmitted(F, Code, Size, Details);
581 void JIT::NotifyFreeingMachineCode(void *OldPtr) {
582 MutexGuard locked(lock);
583 for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) {
584 EventListeners[I]->NotifyFreeingMachineCode(OldPtr);
588 /// runJITOnFunction - Run the FunctionPassManager full of
589 /// just-in-time compilation passes on F, hopefully filling in
590 /// GlobalAddress[F] with the address of F's machine code.
592 void JIT::runJITOnFunction(Function *F, MachineCodeInfo *MCI) {
593 MutexGuard locked(lock);
595 class MCIListener : public JITEventListener {
596 MachineCodeInfo *const MCI;
597 public:
598 MCIListener(MachineCodeInfo *mci) : MCI(mci) {}
599 virtual void NotifyFunctionEmitted(const Function &,
600 void *Code, size_t Size,
601 const EmittedFunctionDetails &) {
602 MCI->setAddress(Code);
603 MCI->setSize(Size);
606 MCIListener MCIL(MCI);
607 if (MCI)
608 RegisterJITEventListener(&MCIL);
610 runJITOnFunctionUnlocked(F, locked);
612 if (MCI)
613 UnregisterJITEventListener(&MCIL);
616 void JIT::runJITOnFunctionUnlocked(Function *F, const MutexGuard &locked) {
617 assert(!isAlreadyCodeGenerating && "Error: Recursive compilation detected!");
619 jitTheFunction(F, locked);
621 // If the function referred to another function that had not yet been
622 // read from bitcode, and we are jitting non-lazily, emit it now.
623 while (!jitstate->getPendingFunctions(locked).empty()) {
624 Function *PF = jitstate->getPendingFunctions(locked).back();
625 jitstate->getPendingFunctions(locked).pop_back();
627 assert(!PF->hasAvailableExternallyLinkage() &&
628 "Externally-defined function should not be in pending list.");
630 jitTheFunction(PF, locked);
632 // Now that the function has been jitted, ask the JITEmitter to rewrite
633 // the stub with real address of the function.
634 updateFunctionStub(PF);
638 void JIT::jitTheFunction(Function *F, const MutexGuard &locked) {
639 isAlreadyCodeGenerating = true;
640 jitstate->getPM(locked).run(*F);
641 isAlreadyCodeGenerating = false;
643 // clear basic block addresses after this function is done
644 getBasicBlockAddressMap(locked).clear();
647 /// getPointerToFunction - This method is used to get the address of the
648 /// specified function, compiling it if necessary.
650 void *JIT::getPointerToFunction(Function *F) {
652 if (void *Addr = getPointerToGlobalIfAvailable(F))
653 return Addr; // Check if function already code gen'd
655 MutexGuard locked(lock);
657 // Now that this thread owns the lock, make sure we read in the function if it
658 // exists in this Module.
659 std::string ErrorMsg;
660 if (F->Materialize(&ErrorMsg)) {
661 report_fatal_error("Error reading function '" + F->getName()+
662 "' from bitcode file: " + ErrorMsg);
665 // ... and check if another thread has already code gen'd the function.
666 if (void *Addr = getPointerToGlobalIfAvailable(F))
667 return Addr;
669 if (F->isDeclaration() || F->hasAvailableExternallyLinkage()) {
670 bool AbortOnFailure = !F->hasExternalWeakLinkage();
671 void *Addr = getPointerToNamedFunction(F->getName(), AbortOnFailure);
672 addGlobalMapping(F, Addr);
673 return Addr;
676 runJITOnFunctionUnlocked(F, locked);
678 void *Addr = getPointerToGlobalIfAvailable(F);
679 assert(Addr && "Code generation didn't add function to GlobalAddress table!");
680 return Addr;
683 void JIT::addPointerToBasicBlock(const BasicBlock *BB, void *Addr) {
684 MutexGuard locked(lock);
686 BasicBlockAddressMapTy::iterator I =
687 getBasicBlockAddressMap(locked).find(BB);
688 if (I == getBasicBlockAddressMap(locked).end()) {
689 getBasicBlockAddressMap(locked)[BB] = Addr;
690 } else {
691 // ignore repeats: some BBs can be split into few MBBs?
695 void JIT::clearPointerToBasicBlock(const BasicBlock *BB) {
696 MutexGuard locked(lock);
697 getBasicBlockAddressMap(locked).erase(BB);
700 void *JIT::getPointerToBasicBlock(BasicBlock *BB) {
701 // make sure it's function is compiled by JIT
702 (void)getPointerToFunction(BB->getParent());
704 // resolve basic block address
705 MutexGuard locked(lock);
707 BasicBlockAddressMapTy::iterator I =
708 getBasicBlockAddressMap(locked).find(BB);
709 if (I != getBasicBlockAddressMap(locked).end()) {
710 return I->second;
711 } else {
712 assert(0 && "JIT does not have BB address for address-of-label, was"
713 " it eliminated by optimizer?");
714 return 0;
718 /// getOrEmitGlobalVariable - Return the address of the specified global
719 /// variable, possibly emitting it to memory if needed. This is used by the
720 /// Emitter.
721 void *JIT::getOrEmitGlobalVariable(const GlobalVariable *GV) {
722 MutexGuard locked(lock);
724 void *Ptr = getPointerToGlobalIfAvailable(GV);
725 if (Ptr) return Ptr;
727 // If the global is external, just remember the address.
728 if (GV->isDeclaration() || GV->hasAvailableExternallyLinkage()) {
729 #if HAVE___DSO_HANDLE
730 if (GV->getName() == "__dso_handle")
731 return (void*)&__dso_handle;
732 #endif
733 Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(GV->getName());
734 if (Ptr == 0) {
735 report_fatal_error("Could not resolve external global address: "
736 +GV->getName());
738 addGlobalMapping(GV, Ptr);
739 } else {
740 // If the global hasn't been emitted to memory yet, allocate space and
741 // emit it into memory.
742 Ptr = getMemoryForGV(GV);
743 addGlobalMapping(GV, Ptr);
744 EmitGlobalVariable(GV); // Initialize the variable.
746 return Ptr;
749 /// recompileAndRelinkFunction - This method is used to force a function
750 /// which has already been compiled, to be compiled again, possibly
751 /// after it has been modified. Then the entry to the old copy is overwritten
752 /// with a branch to the new copy. If there was no old copy, this acts
753 /// just like JIT::getPointerToFunction().
755 void *JIT::recompileAndRelinkFunction(Function *F) {
756 void *OldAddr = getPointerToGlobalIfAvailable(F);
758 // If it's not already compiled there is no reason to patch it up.
759 if (OldAddr == 0) { return getPointerToFunction(F); }
761 // Delete the old function mapping.
762 addGlobalMapping(F, 0);
764 // Recodegen the function
765 runJITOnFunction(F);
767 // Update state, forward the old function to the new function.
768 void *Addr = getPointerToGlobalIfAvailable(F);
769 assert(Addr && "Code generation didn't add function to GlobalAddress table!");
770 TJI.replaceMachineCodeForFunction(OldAddr, Addr);
771 return Addr;
774 /// getMemoryForGV - This method abstracts memory allocation of global
775 /// variable so that the JIT can allocate thread local variables depending
776 /// on the target.
778 char* JIT::getMemoryForGV(const GlobalVariable* GV) {
779 char *Ptr;
781 // GlobalVariable's which are not "constant" will cause trouble in a server
782 // situation. It's returned in the same block of memory as code which may
783 // not be writable.
784 if (isGVCompilationDisabled() && !GV->isConstant()) {
785 report_fatal_error("Compilation of non-internal GlobalValue is disabled!");
788 // Some applications require globals and code to live together, so they may
789 // be allocated into the same buffer, but in general globals are allocated
790 // through the memory manager which puts them near the code but not in the
791 // same buffer.
792 const Type *GlobalType = GV->getType()->getElementType();
793 size_t S = getTargetData()->getTypeAllocSize(GlobalType);
794 size_t A = getTargetData()->getPreferredAlignment(GV);
795 if (GV->isThreadLocal()) {
796 MutexGuard locked(lock);
797 Ptr = TJI.allocateThreadLocalMemory(S);
798 } else if (TJI.allocateSeparateGVMemory()) {
799 if (A <= 8) {
800 Ptr = (char*)malloc(S);
801 } else {
802 // Allocate S+A bytes of memory, then use an aligned pointer within that
803 // space.
804 Ptr = (char*)malloc(S+A);
805 unsigned MisAligned = ((intptr_t)Ptr & (A-1));
806 Ptr = Ptr + (MisAligned ? (A-MisAligned) : 0);
808 } else if (AllocateGVsWithCode) {
809 Ptr = (char*)JCE->allocateSpace(S, A);
810 } else {
811 Ptr = (char*)JCE->allocateGlobal(S, A);
813 return Ptr;
816 void JIT::addPendingFunction(Function *F) {
817 MutexGuard locked(lock);
818 jitstate->getPendingFunctions(locked).push_back(F);
822 JITEventListener::~JITEventListener() {}