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/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/ExecutionEngine/JITMemoryManager.h" 27 #include "llvm/Target/TargetData.h" 28 #include "llvm/Target/TargetMachine.h" 29 #include "llvm/Target/TargetJITInfo.h" 30 #include "llvm/Support/Dwarf.h" 31 #include "llvm/Support/ErrorHandling.h" 32 #include "llvm/Support/ManagedStatic.h" 33 #include "llvm/Support/MutexGuard.h" 34 #include "llvm/Support/DynamicLibrary.h" 35 #include "llvm/Config/config.h" 36 37 using namespace llvm; 38 39 #ifdef __APPLE__ 40 // Apple gcc defaults to -fuse-cxa-atexit (i.e. calls __cxa_atexit instead 41 // of atexit). It passes the address of linker generated symbol __dso_handle 42 // to the function. 43 // This configuration change happened at version 5330. 44 # include <AvailabilityMacros.h> 45 # if defined(MAC_OS_X_VERSION_10_4) && \ 46 ((MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_4) || \ 47 (MAC_OS_X_VERSION_MIN_REQUIRED == MAC_OS_X_VERSION_10_4 && \ 48 __APPLE_CC__ >= 5330)) 49 # ifndef HAVE___DSO_HANDLE 50 # define HAVE___DSO_HANDLE 1 51 # endif 52 # endif 53 #endif 54 55 #if HAVE___DSO_HANDLE 56 extern void *__dso_handle __attribute__ ((__visibility__ ("hidden"))); 57 #endif 58 59 namespace { 60 61 static struct RegisterJIT { 62 RegisterJIT() { JIT::Register(); } 63 } JITRegistrator; 64 65 } 66 67 extern "C" void LLVMLinkInJIT() { 68 } 69 70 // Determine whether we can register EH tables. 71 #if (defined(__GNUC__) && !defined(__ARM_EABI__) && \ 72 !defined(__USING_SJLJ_EXCEPTIONS__)) 73 #define HAVE_EHTABLE_SUPPORT 1 74 #else 75 #define HAVE_EHTABLE_SUPPORT 0 76 #endif 77 78 #if HAVE_EHTABLE_SUPPORT 79 80 // libgcc defines the __register_frame function to dynamically register new 81 // dwarf frames for exception handling. This functionality is not portable 82 // across compilers and is only provided by GCC. We use the __register_frame 83 // function here so that code generated by the JIT cooperates with the unwinding 84 // runtime of libgcc. When JITting with exception handling enable, LLVM 85 // generates dwarf frames and registers it to libgcc with __register_frame. 86 // 87 // The __register_frame function works with Linux. 88 // 89 // Unfortunately, this functionality seems to be in libgcc after the unwinding 90 // library of libgcc for darwin was written. The code for darwin overwrites the 91 // value updated by __register_frame with a value fetched with "keymgr". 92 // "keymgr" is an obsolete functionality, which should be rewritten some day. 93 // In the meantime, since "keymgr" is on all libgccs shipped with apple-gcc, we 94 // need a workaround in LLVM which uses the "keymgr" to dynamically modify the 95 // values of an opaque key, used by libgcc to find dwarf tables. 96 97 extern "C" void __register_frame(void*); 98 extern "C" void __deregister_frame(void*); 99 100 #if defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED <= 1050 101 # define USE_KEYMGR 1 102 #else 103 # define USE_KEYMGR 0 104 #endif 105 106 #if USE_KEYMGR 107 108 namespace { 109 110 // LibgccObject - This is the structure defined in libgcc. There is no #include 111 // provided for this structure, so we also define it here. libgcc calls it 112 // "struct object". The structure is undocumented in libgcc. 113 struct LibgccObject { 114 void *unused1; 115 void *unused2; 116 void *unused3; 117 118 /// frame - Pointer to the exception table. 119 void *frame; 120 121 /// encoding - The encoding of the object? 122 union { 123 struct { 124 unsigned long sorted : 1; 125 unsigned long from_array : 1; 126 unsigned long mixed_encoding : 1; 127 unsigned long encoding : 8; 128 unsigned long count : 21; 129 } b; 130 size_t i; 131 } encoding; 132 133 /// fde_end - libgcc defines this field only if some macro is defined. We 134 /// include this field even if it may not there, to make libgcc happy. 135 char *fde_end; 136 137 /// next - At least we know it's a chained list! 138 struct LibgccObject *next; 139 }; 140 141 // "kemgr" stuff. Apparently, all frame tables are stored there. 142 extern "C" void _keymgr_set_and_unlock_processwide_ptr(int, void *); 143 extern "C" void *_keymgr_get_and_lock_processwide_ptr(int); 144 #define KEYMGR_GCC3_DW2_OBJ_LIST 302 /* Dwarf2 object list */ 145 146 /// LibgccObjectInfo - libgcc defines this struct as km_object_info. It 147 /// probably contains all dwarf tables that are loaded. 148 struct LibgccObjectInfo { 149 150 /// seenObjects - LibgccObjects already parsed by the unwinding runtime. 151 /// 152 struct LibgccObject* seenObjects; 153 154 /// unseenObjects - LibgccObjects not parsed yet by the unwinding runtime. 155 /// 156 struct LibgccObject* unseenObjects; 157 158 unsigned unused[2]; 159 }; 160 161 /// darwin_register_frame - Since __register_frame does not work with darwin's 162 /// libgcc,we provide our own function, which "tricks" libgcc by modifying the 163 /// "Dwarf2 object list" key. 164 void DarwinRegisterFrame(void* FrameBegin) { 165 // Get the key. 166 LibgccObjectInfo* LOI = (struct LibgccObjectInfo*) 167 _keymgr_get_and_lock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST); 168 assert(LOI && "This should be preallocated by the runtime"); 169 170 // Allocate a new LibgccObject to represent this frame. Deallocation of this 171 // object may be impossible: since darwin code in libgcc was written after 172 // the ability to dynamically register frames, things may crash if we 173 // deallocate it. 174 struct LibgccObject* ob = (struct LibgccObject*) 175 malloc(sizeof(struct LibgccObject)); 176 177 // Do like libgcc for the values of the field. 178 ob->unused1 = (void *)-1; 179 ob->unused2 = 0; 180 ob->unused3 = 0; 181 ob->frame = FrameBegin; 182 ob->encoding.i = 0; 183 ob->encoding.b.encoding = llvm::dwarf::DW_EH_PE_omit; 184 185 // Put the info on both places, as libgcc uses the first or the second 186 // field. Note that we rely on having two pointers here. If fde_end was a 187 // char, things would get complicated. 188 ob->fde_end = (char*)LOI->unseenObjects; 189 ob->next = LOI->unseenObjects; 190 191 // Update the key's unseenObjects list. 192 LOI->unseenObjects = ob; 193 194 // Finally update the "key". Apparently, libgcc requires it. 195 _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST, 196 LOI); 197 198 } 199 200 } 201 #endif // __APPLE__ 202 #endif // HAVE_EHTABLE_SUPPORT 203 204 /// createJIT - This is the factory method for creating a JIT for the current 205 /// machine, it does not fall back to the interpreter. This takes ownership 206 /// of the module. 207 ExecutionEngine *JIT::createJIT(Module *M, 208 std::string *ErrorStr, 209 JITMemoryManager *JMM, 210 bool GVsWithCode, 211 TargetMachine *TM) { 212 // Try to register the program as a source of symbols to resolve against. 213 // 214 // FIXME: Don't do this here. 215 sys::DynamicLibrary::LoadLibraryPermanently(0, NULL); 216 217 // If the target supports JIT code generation, create the JIT. 218 if (TargetJITInfo *TJ = TM->getJITInfo()) { 219 return new JIT(M, *TM, *TJ, JMM, GVsWithCode); 220 } else { 221 if (ErrorStr) 222 *ErrorStr = "target does not support JIT code generation"; 223 return 0; 224 } 225 } 226 227 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); 237 } 238 void Remove(JIT *jit) { 239 MutexGuard guard(Lock); 240 JITs.erase(jit); 241 } 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); 251 } 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); 255 } 256 }; 257 ManagedStatic<JitPool> AllJits; 258 } 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); 267 } 268 } 269 270 JIT::JIT(Module *M, TargetMachine &tm, TargetJITInfo &tji, 271 JITMemoryManager *jmm, bool GVsWithCode) 272 : ExecutionEngine(M), TM(tm), TJI(tji), 273 JMM(jmm ? jmm : JITMemoryManager::CreateDefaultMemManager()), 274 AllocateGVsWithCode(GVsWithCode), isAlreadyCodeGenerating(false) { 275 setTargetData(TM.getTargetData()); 276 277 jitstate = new JITState(M); 278 279 // Initialize JCE 280 JCE = createEmitter(*this, JMM, TM); 281 282 // Register in global list of all JITs. 283 AllJits->Add(this); 284 285 // Add target data 286 MutexGuard locked(lock); 287 FunctionPassManager &PM = jitstate->getPM(locked); 288 PM.add(new TargetData(*TM.getTargetData())); 289 290 // Turn the machine code intermediate representation into bytes in memory that 291 // may be executed. 292 if (TM.addPassesToEmitMachineCode(PM, *JCE)) { 293 report_fatal_error("Target does not support machine code emission!"); 294 } 295 296 // Register routine for informing unwinding runtime about new EH frames 297 #if HAVE_EHTABLE_SUPPORT 298 #if USE_KEYMGR 299 struct LibgccObjectInfo* LOI = (struct LibgccObjectInfo*) 300 _keymgr_get_and_lock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST); 301 302 // The key is created on demand, and libgcc creates it the first time an 303 // exception occurs. Since we need the key to register frames, we create 304 // it now. 305 if (!LOI) 306 LOI = (LibgccObjectInfo*)calloc(sizeof(struct LibgccObjectInfo), 1); 307 _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST, LOI); 308 InstallExceptionTableRegister(DarwinRegisterFrame); 309 // Not sure about how to deregister on Darwin. 310 #else 311 InstallExceptionTableRegister(__register_frame); 312 InstallExceptionTableDeregister(__deregister_frame); 313 #endif // __APPLE__ 314 #endif // HAVE_EHTABLE_SUPPORT 315 316 // Initialize passes. 317 PM.doInitialization(); 318 } 319 320 JIT::~JIT() { 321 // Unregister all exception tables registered by this JIT. 322 DeregisterAllTables(); 323 // Cleanup. 324 AllJits->Remove(this); 325 delete jitstate; 326 delete JCE; 327 // JMM is a ownership of JCE, so we no need delete JMM here. 328 delete &TM; 329 } 330 331 /// addModule - Add a new Module to the JIT. If we previously removed the last 332 /// Module, we need re-initialize jitstate with a valid Module. 333 void JIT::addModule(Module *M) { 334 MutexGuard locked(lock); 335 336 if (Modules.empty()) { 337 assert(!jitstate && "jitstate should be NULL if Modules vector is empty!"); 338 339 jitstate = new JITState(M); 340 341 FunctionPassManager &PM = jitstate->getPM(locked); 342 PM.add(new TargetData(*TM.getTargetData())); 343 344 // Turn the machine code intermediate representation into bytes in memory 345 // that may be executed. 346 if (TM.addPassesToEmitMachineCode(PM, *JCE)) { 347 report_fatal_error("Target does not support machine code emission!"); 348 } 349 350 // Initialize passes. 351 PM.doInitialization(); 352 } 353 354 ExecutionEngine::addModule(M); 355 } 356 357 /// removeModule - If we are removing the last Module, invalidate the jitstate 358 /// since the PassManager it contains references a released Module. 359 bool JIT::removeModule(Module *M) { 360 bool result = ExecutionEngine::removeModule(M); 361 362 MutexGuard locked(lock); 363 364 if (jitstate && jitstate->getModule() == M) { 365 delete jitstate; 366 jitstate = 0; 367 } 368 369 if (!jitstate && !Modules.empty()) { 370 jitstate = new JITState(Modules[0]); 371 372 FunctionPassManager &PM = jitstate->getPM(locked); 373 PM.add(new TargetData(*TM.getTargetData())); 374 375 // Turn the machine code intermediate representation into bytes in memory 376 // that may be executed. 377 if (TM.addPassesToEmitMachineCode(PM, *JCE)) { 378 report_fatal_error("Target does not support machine code emission!"); 379 } 380 381 // Initialize passes. 382 PM.doInitialization(); 383 } 384 return result; 385 } 386 387 /// run - Start execution with the specified function and arguments. 388 /// 389 GenericValue JIT::runFunction(Function *F, 390 const std::vector<GenericValue> &ArgValues) { 391 assert(F && "Function *F was null at entry to run()"); 392 393 void *FPtr = getPointerToFunction(F); 394 assert(FPtr && "Pointer to fn's code was null after getPointerToFunction"); 395 FunctionType *FTy = F->getFunctionType(); 396 Type *RetTy = FTy->getReturnType(); 397 398 assert((FTy->getNumParams() == ArgValues.size() || 399 (FTy->isVarArg() && FTy->getNumParams() <= ArgValues.size())) && 400 "Wrong number of arguments passed into function!"); 401 assert(FTy->getNumParams() == ArgValues.size() && 402 "This doesn't support passing arguments through varargs (yet)!"); 403 404 // Handle some common cases first. These cases correspond to common `main' 405 // prototypes. 406 if (RetTy->isIntegerTy(32) || RetTy->isVoidTy()) { 407 switch (ArgValues.size()) { 408 case 3: 409 if (FTy->getParamType(0)->isIntegerTy(32) && 410 FTy->getParamType(1)->isPointerTy() && 411 FTy->getParamType(2)->isPointerTy()) { 412 int (*PF)(int, char **, const char **) = 413 (int(*)(int, char **, const char **))(intptr_t)FPtr; 414 415 // Call the function. 416 GenericValue rv; 417 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(), 418 (char **)GVTOP(ArgValues[1]), 419 (const char **)GVTOP(ArgValues[2]))); 420 return rv; 421 } 422 break; 423 case 2: 424 if (FTy->getParamType(0)->isIntegerTy(32) && 425 FTy->getParamType(1)->isPointerTy()) { 426 int (*PF)(int, char **) = (int(*)(int, char **))(intptr_t)FPtr; 427 428 // Call the function. 429 GenericValue rv; 430 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(), 431 (char **)GVTOP(ArgValues[1]))); 432 return rv; 433 } 434 break; 435 case 1: 436 if (FTy->getParamType(0)->isIntegerTy(32)) { 437 GenericValue rv; 438 int (*PF)(int) = (int(*)(int))(intptr_t)FPtr; 439 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue())); 440 return rv; 441 } 442 if (FTy->getParamType(0)->isPointerTy()) { 443 GenericValue rv; 444 int (*PF)(char *) = (int(*)(char *))(intptr_t)FPtr; 445 rv.IntVal = APInt(32, PF((char*)GVTOP(ArgValues[0]))); 446 return rv; 447 } 448 break; 449 } 450 } 451 452 // Handle cases where no arguments are passed first. 453 if (ArgValues.empty()) { 454 GenericValue rv; 455 switch (RetTy->getTypeID()) { 456 default: llvm_unreachable("Unknown return type for function call!"); 457 case Type::IntegerTyID: { 458 unsigned BitWidth = cast<IntegerType>(RetTy)->getBitWidth(); 459 if (BitWidth == 1) 460 rv.IntVal = APInt(BitWidth, ((bool(*)())(intptr_t)FPtr)()); 461 else if (BitWidth <= 8) 462 rv.IntVal = APInt(BitWidth, ((char(*)())(intptr_t)FPtr)()); 463 else if (BitWidth <= 16) 464 rv.IntVal = APInt(BitWidth, ((short(*)())(intptr_t)FPtr)()); 465 else if (BitWidth <= 32) 466 rv.IntVal = APInt(BitWidth, ((int(*)())(intptr_t)FPtr)()); 467 else if (BitWidth <= 64) 468 rv.IntVal = APInt(BitWidth, ((int64_t(*)())(intptr_t)FPtr)()); 469 else 470 llvm_unreachable("Integer types > 64 bits not supported"); 471 return rv; 472 } 473 case Type::VoidTyID: 474 rv.IntVal = APInt(32, ((int(*)())(intptr_t)FPtr)()); 475 return rv; 476 case Type::FloatTyID: 477 rv.FloatVal = ((float(*)())(intptr_t)FPtr)(); 478 return rv; 479 case Type::DoubleTyID: 480 rv.DoubleVal = ((double(*)())(intptr_t)FPtr)(); 481 return rv; 482 case Type::X86_FP80TyID: 483 case Type::FP128TyID: 484 case Type::PPC_FP128TyID: 485 llvm_unreachable("long double not supported yet"); 486 case Type::PointerTyID: 487 return PTOGV(((void*(*)())(intptr_t)FPtr)()); 488 } 489 } 490 491 // Okay, this is not one of our quick and easy cases. Because we don't have a 492 // full FFI, we have to codegen a nullary stub function that just calls the 493 // function we are interested in, passing in constants for all of the 494 // arguments. Make this function and return. 495 496 // First, create the function. 497 FunctionType *STy=FunctionType::get(RetTy, false); 498 Function *Stub = Function::Create(STy, Function::InternalLinkage, "", 499 F->getParent()); 500 501 // Insert a basic block. 502 BasicBlock *StubBB = BasicBlock::Create(F->getContext(), "", Stub); 503 504 // Convert all of the GenericValue arguments over to constants. Note that we 505 // currently don't support varargs. 506 SmallVector<Value*, 8> Args; 507 for (unsigned i = 0, e = ArgValues.size(); i != e; ++i) { 508 Constant *C = 0; 509 Type *ArgTy = FTy->getParamType(i); 510 const GenericValue &AV = ArgValues[i]; 511 switch (ArgTy->getTypeID()) { 512 default: llvm_unreachable("Unknown argument type for function call!"); 513 case Type::IntegerTyID: 514 C = ConstantInt::get(F->getContext(), AV.IntVal); 515 break; 516 case Type::FloatTyID: 517 C = ConstantFP::get(F->getContext(), APFloat(AV.FloatVal)); 518 break; 519 case Type::DoubleTyID: 520 C = ConstantFP::get(F->getContext(), APFloat(AV.DoubleVal)); 521 break; 522 case Type::PPC_FP128TyID: 523 case Type::X86_FP80TyID: 524 case Type::FP128TyID: 525 C = ConstantFP::get(F->getContext(), APFloat(AV.IntVal)); 526 break; 527 case Type::PointerTyID: 528 void *ArgPtr = GVTOP(AV); 529 if (sizeof(void*) == 4) 530 C = ConstantInt::get(Type::getInt32Ty(F->getContext()), 531 (int)(intptr_t)ArgPtr); 532 else 533 C = ConstantInt::get(Type::getInt64Ty(F->getContext()), 534 (intptr_t)ArgPtr); 535 // Cast the integer to pointer 536 C = ConstantExpr::getIntToPtr(C, ArgTy); 537 break; 538 } 539 Args.push_back(C); 540 } 541 542 CallInst *TheCall = CallInst::Create(F, Args, "", StubBB); 543 TheCall->setCallingConv(F->getCallingConv()); 544 TheCall->setTailCall(); 545 if (!TheCall->getType()->isVoidTy()) 546 // Return result of the call. 547 ReturnInst::Create(F->getContext(), TheCall, StubBB); 548 else 549 ReturnInst::Create(F->getContext(), StubBB); // Just return void. 550 551 // Finally, call our nullary stub function. 552 GenericValue Result = runFunction(Stub, std::vector<GenericValue>()); 553 // Erase it, since no other function can have a reference to it. 554 Stub->eraseFromParent(); 555 // And return the result. 556 return Result; 557 } 558 559 void JIT::RegisterJITEventListener(JITEventListener *L) { 560 if (L == NULL) 561 return; 562 MutexGuard locked(lock); 563 EventListeners.push_back(L); 564 } 565 void JIT::UnregisterJITEventListener(JITEventListener *L) { 566 if (L == NULL) 567 return; 568 MutexGuard locked(lock); 569 std::vector<JITEventListener*>::reverse_iterator I= 570 std::find(EventListeners.rbegin(), EventListeners.rend(), L); 571 if (I != EventListeners.rend()) { 572 std::swap(*I, EventListeners.back()); 573 EventListeners.pop_back(); 574 } 575 } 576 void JIT::NotifyFunctionEmitted( 577 const Function &F, 578 void *Code, size_t Size, 579 const JITEvent_EmittedFunctionDetails &Details) { 580 MutexGuard locked(lock); 581 for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) { 582 EventListeners[I]->NotifyFunctionEmitted(F, Code, Size, Details); 583 } 584 } 585 586 void JIT::NotifyFreeingMachineCode(void *OldPtr) { 587 MutexGuard locked(lock); 588 for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) { 589 EventListeners[I]->NotifyFreeingMachineCode(OldPtr); 590 } 591 } 592 593 /// runJITOnFunction - Run the FunctionPassManager full of 594 /// just-in-time compilation passes on F, hopefully filling in 595 /// GlobalAddress[F] with the address of F's machine code. 596 /// 597 void JIT::runJITOnFunction(Function *F, MachineCodeInfo *MCI) { 598 MutexGuard locked(lock); 599 600 class MCIListener : public JITEventListener { 601 MachineCodeInfo *const MCI; 602 public: 603 MCIListener(MachineCodeInfo *mci) : MCI(mci) {} 604 virtual void NotifyFunctionEmitted(const Function &, 605 void *Code, size_t Size, 606 const EmittedFunctionDetails &) { 607 MCI->setAddress(Code); 608 MCI->setSize(Size); 609 } 610 }; 611 MCIListener MCIL(MCI); 612 if (MCI) 613 RegisterJITEventListener(&MCIL); 614 615 runJITOnFunctionUnlocked(F, locked); 616 617 if (MCI) 618 UnregisterJITEventListener(&MCIL); 619 } 620 621 void JIT::runJITOnFunctionUnlocked(Function *F, const MutexGuard &locked) { 622 assert(!isAlreadyCodeGenerating && "Error: Recursive compilation detected!"); 623 624 jitTheFunction(F, locked); 625 626 // If the function referred to another function that had not yet been 627 // read from bitcode, and we are jitting non-lazily, emit it now. 628 while (!jitstate->getPendingFunctions(locked).empty()) { 629 Function *PF = jitstate->getPendingFunctions(locked).back(); 630 jitstate->getPendingFunctions(locked).pop_back(); 631 632 assert(!PF->hasAvailableExternallyLinkage() && 633 "Externally-defined function should not be in pending list."); 634 635 jitTheFunction(PF, locked); 636 637 // Now that the function has been jitted, ask the JITEmitter to rewrite 638 // the stub with real address of the function. 639 updateFunctionStub(PF); 640 } 641 } 642 643 void JIT::jitTheFunction(Function *F, const MutexGuard &locked) { 644 isAlreadyCodeGenerating = true; 645 jitstate->getPM(locked).run(*F); 646 isAlreadyCodeGenerating = false; 647 648 // clear basic block addresses after this function is done 649 getBasicBlockAddressMap(locked).clear(); 650 } 651 652 /// getPointerToFunction - This method is used to get the address of the 653 /// specified function, compiling it if necessary. 654 /// 655 void *JIT::getPointerToFunction(Function *F) { 656 657 if (void *Addr = getPointerToGlobalIfAvailable(F)) 658 return Addr; // Check if function already code gen'd 659 660 MutexGuard locked(lock); 661 662 // Now that this thread owns the lock, make sure we read in the function if it 663 // exists in this Module. 664 std::string ErrorMsg; 665 if (F->Materialize(&ErrorMsg)) { 666 report_fatal_error("Error reading function '" + F->getName()+ 667 "' from bitcode file: " + ErrorMsg); 668 } 669 670 // ... and check if another thread has already code gen'd the function. 671 if (void *Addr = getPointerToGlobalIfAvailable(F)) 672 return Addr; 673 674 if (F->isDeclaration() || F->hasAvailableExternallyLinkage()) { 675 bool AbortOnFailure = !F->hasExternalWeakLinkage(); 676 void *Addr = getPointerToNamedFunction(F->getName(), AbortOnFailure); 677 addGlobalMapping(F, Addr); 678 return Addr; 679 } 680 681 runJITOnFunctionUnlocked(F, locked); 682 683 void *Addr = getPointerToGlobalIfAvailable(F); 684 assert(Addr && "Code generation didn't add function to GlobalAddress table!"); 685 return Addr; 686 } 687 688 void JIT::addPointerToBasicBlock(const BasicBlock *BB, void *Addr) { 689 MutexGuard locked(lock); 690 691 BasicBlockAddressMapTy::iterator I = 692 getBasicBlockAddressMap(locked).find(BB); 693 if (I == getBasicBlockAddressMap(locked).end()) { 694 getBasicBlockAddressMap(locked)[BB] = Addr; 695 } else { 696 // ignore repeats: some BBs can be split into few MBBs? 697 } 698 } 699 700 void JIT::clearPointerToBasicBlock(const BasicBlock *BB) { 701 MutexGuard locked(lock); 702 getBasicBlockAddressMap(locked).erase(BB); 703 } 704 705 void *JIT::getPointerToBasicBlock(BasicBlock *BB) { 706 // make sure it's function is compiled by JIT 707 (void)getPointerToFunction(BB->getParent()); 708 709 // resolve basic block address 710 MutexGuard locked(lock); 711 712 BasicBlockAddressMapTy::iterator I = 713 getBasicBlockAddressMap(locked).find(BB); 714 if (I != getBasicBlockAddressMap(locked).end()) { 715 return I->second; 716 } else { 717 llvm_unreachable("JIT does not have BB address for address-of-label, was" 718 " it eliminated by optimizer?"); 719 } 720 } 721 722 void *JIT::getPointerToNamedFunction(const std::string &Name, 723 bool AbortOnFailure){ 724 if (!isSymbolSearchingDisabled()) { 725 void *ptr = JMM->getPointerToNamedFunction(Name, false); 726 if (ptr) 727 return ptr; 728 } 729 730 /// If a LazyFunctionCreator is installed, use it to get/create the function. 731 if (LazyFunctionCreator) 732 if (void *RP = LazyFunctionCreator(Name)) 733 return RP; 734 735 if (AbortOnFailure) { 736 report_fatal_error("Program used external function '"+Name+ 737 "' which could not be resolved!"); 738 } 739 return 0; 740 } 741 742 743 /// getOrEmitGlobalVariable - Return the address of the specified global 744 /// variable, possibly emitting it to memory if needed. This is used by the 745 /// Emitter. 746 void *JIT::getOrEmitGlobalVariable(const GlobalVariable *GV) { 747 MutexGuard locked(lock); 748 749 void *Ptr = getPointerToGlobalIfAvailable(GV); 750 if (Ptr) return Ptr; 751 752 // If the global is external, just remember the address. 753 if (GV->isDeclaration() || GV->hasAvailableExternallyLinkage()) { 754 #if HAVE___DSO_HANDLE 755 if (GV->getName() == "__dso_handle") 756 return (void*)&__dso_handle; 757 #endif 758 Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(GV->getName()); 759 if (Ptr == 0) { 760 report_fatal_error("Could not resolve external global address: " 761 +GV->getName()); 762 } 763 addGlobalMapping(GV, Ptr); 764 } else { 765 // If the global hasn't been emitted to memory yet, allocate space and 766 // emit it into memory. 767 Ptr = getMemoryForGV(GV); 768 addGlobalMapping(GV, Ptr); 769 EmitGlobalVariable(GV); // Initialize the variable. 770 } 771 return Ptr; 772 } 773 774 /// recompileAndRelinkFunction - This method is used to force a function 775 /// which has already been compiled, to be compiled again, possibly 776 /// after it has been modified. Then the entry to the old copy is overwritten 777 /// with a branch to the new copy. If there was no old copy, this acts 778 /// just like JIT::getPointerToFunction(). 779 /// 780 void *JIT::recompileAndRelinkFunction(Function *F) { 781 void *OldAddr = getPointerToGlobalIfAvailable(F); 782 783 // If it's not already compiled there is no reason to patch it up. 784 if (OldAddr == 0) { return getPointerToFunction(F); } 785 786 // Delete the old function mapping. 787 addGlobalMapping(F, 0); 788 789 // Recodegen the function 790 runJITOnFunction(F); 791 792 // Update state, forward the old function to the new function. 793 void *Addr = getPointerToGlobalIfAvailable(F); 794 assert(Addr && "Code generation didn't add function to GlobalAddress table!"); 795 TJI.replaceMachineCodeForFunction(OldAddr, Addr); 796 return Addr; 797 } 798 799 /// getMemoryForGV - This method abstracts memory allocation of global 800 /// variable so that the JIT can allocate thread local variables depending 801 /// on the target. 802 /// 803 char* JIT::getMemoryForGV(const GlobalVariable* GV) { 804 char *Ptr; 805 806 // GlobalVariable's which are not "constant" will cause trouble in a server 807 // situation. It's returned in the same block of memory as code which may 808 // not be writable. 809 if (isGVCompilationDisabled() && !GV->isConstant()) { 810 report_fatal_error("Compilation of non-internal GlobalValue is disabled!"); 811 } 812 813 // Some applications require globals and code to live together, so they may 814 // be allocated into the same buffer, but in general globals are allocated 815 // through the memory manager which puts them near the code but not in the 816 // same buffer. 817 Type *GlobalType = GV->getType()->getElementType(); 818 size_t S = getTargetData()->getTypeAllocSize(GlobalType); 819 size_t A = getTargetData()->getPreferredAlignment(GV); 820 if (GV->isThreadLocal()) { 821 MutexGuard locked(lock); 822 Ptr = TJI.allocateThreadLocalMemory(S); 823 } else if (TJI.allocateSeparateGVMemory()) { 824 if (A <= 8) { 825 Ptr = (char*)malloc(S); 826 } else { 827 // Allocate S+A bytes of memory, then use an aligned pointer within that 828 // space. 829 Ptr = (char*)malloc(S+A); 830 unsigned MisAligned = ((intptr_t)Ptr & (A-1)); 831 Ptr = Ptr + (MisAligned ? (A-MisAligned) : 0); 832 } 833 } else if (AllocateGVsWithCode) { 834 Ptr = (char*)JCE->allocateSpace(S, A); 835 } else { 836 Ptr = (char*)JCE->allocateGlobal(S, A); 837 } 838 return Ptr; 839 } 840 841 void JIT::addPendingFunction(Function *F) { 842 MutexGuard locked(lock); 843 jitstate->getPendingFunctions(locked).push_back(F); 844 } 845 846 847 JITEventListener::~JITEventListener() {} 848