JIT.cpp revision 83a82ac0b4dc6ea6b3e56f9e239a113eb5be5f38
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/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" 35 36using namespace llvm; 37 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 53 54#if HAVE___DSO_HANDLE 55extern void *__dso_handle __attribute__ ((__visibility__ ("hidden"))); 56#endif 57 58namespace { 59 60static struct RegisterJIT { 61 RegisterJIT() { JIT::Register(); } 62} JITRegistrator; 63 64} 65 66extern "C" void LLVMLinkInJIT() { 67} 68 69 70#if defined(__GNUC__) && !defined(__ARM_EABI__) && !defined(__USING_SJLJ_EXCEPTIONS__) 71 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. 78// 79// The __register_frame function works with Linux. 80// 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. 88 89extern "C" void __register_frame(void*); 90 91#if defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED <= 1050 92# define USE_KEYMGR 1 93#else 94# define USE_KEYMGR 0 95#endif 96 97#if USE_KEYMGR 98 99namespace { 100 101// 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. 104struct LibgccObject { 105 void *unused1; 106 void *unused2; 107 void *unused3; 108 109 /// frame - Pointer to the exception table. 110 void *frame; 111 112 /// encoding - The encoding of the object? 113 union { 114 struct { 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; 120 } b; 121 size_t i; 122 } encoding; 123 124 /// 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. 126 char *fde_end; 127 128 /// next - At least we know it's a chained list! 129 struct LibgccObject *next; 130}; 131 132// "kemgr" stuff. Apparently, all frame tables are stored there. 133extern "C" void _keymgr_set_and_unlock_processwide_ptr(int, void *); 134extern "C" void *_keymgr_get_and_lock_processwide_ptr(int); 135#define KEYMGR_GCC3_DW2_OBJ_LIST 302 /* Dwarf2 object list */ 136 137/// LibgccObjectInfo - libgcc defines this struct as km_object_info. It 138/// probably contains all dwarf tables that are loaded. 139struct LibgccObjectInfo { 140 141 /// seenObjects - LibgccObjects already parsed by the unwinding runtime. 142 /// 143 struct LibgccObject* seenObjects; 144 145 /// unseenObjects - LibgccObjects not parsed yet by the unwinding runtime. 146 /// 147 struct LibgccObject* unseenObjects; 148 149 unsigned unused[2]; 150}; 151 152/// 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. 155void DarwinRegisterFrame(void* FrameBegin) { 156 // Get the key. 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"); 160 161 // 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 164 // deallocate it. 165 struct LibgccObject* ob = (struct LibgccObject*) 166 malloc(sizeof(struct LibgccObject)); 167 168 // Do like libgcc for the values of the field. 169 ob->unused1 = (void *)-1; 170 ob->unused2 = 0; 171 ob->unused3 = 0; 172 ob->frame = FrameBegin; 173 ob->encoding.i = 0; 174 ob->encoding.b.encoding = llvm::dwarf::DW_EH_PE_omit; 175 176 // 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; 181 182 // Update the key's unseenObjects list. 183 LOI->unseenObjects = ob; 184 185 // Finally update the "key". Apparently, libgcc requires it. 186 _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST, 187 LOI); 188 189} 190 191} 192#endif // __APPLE__ 193#endif // __GNUC__ 194 195/// 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 197/// of the module. 198ExecutionEngine *ExecutionEngine::createJIT(Module *M, 199 std::string *ErrorStr, 200 JITMemoryManager *JMM, 201 CodeGenOpt::Level OptLevel, 202 bool GVsWithCode, 203 CodeModel::Model CMM) { 204 // Use the defaults for extra parameters. Users can use EngineBuilder to 205 // set them. 206 StringRef MArch = ""; 207 StringRef MCPU = ""; 208 SmallVector<std::string, 1> MAttrs; 209 return JIT::createJIT(M, ErrorStr, JMM, OptLevel, GVsWithCode, CMM, 210 MArch, MCPU, MAttrs); 211} 212 213ExecutionEngine *JIT::createJIT(Module *M, 214 std::string *ErrorStr, 215 JITMemoryManager *JMM, 216 CodeGenOpt::Level OptLevel, 217 bool GVsWithCode, 218 CodeModel::Model CMM, 219 StringRef MArch, 220 StringRef MCPU, 221 const SmallVectorImpl<std::string>& MAttrs) { 222 // Try to register the program as a source of symbols to resolve against. 223 sys::DynamicLibrary::LoadLibraryPermanently(0, NULL); 224 225 // Pick a target either via -march or by guessing the native arch. 226 TargetMachine *TM = JIT::selectTarget(M, MArch, MCPU, MAttrs, ErrorStr); 227 if (!TM || (ErrorStr && ErrorStr->length() > 0)) return 0; 228 TM->setCodeModel(CMM); 229 230 // If the target supports JIT code generation, create a the JIT. 231 if (TargetJITInfo *TJ = TM->getJITInfo()) { 232 return new JIT(M, *TM, *TJ, JMM, OptLevel, GVsWithCode); 233 } else { 234 if (ErrorStr) 235 *ErrorStr = "target does not support JIT code generation"; 236 return 0; 237 } 238} 239 240namespace { 241/// This class supports the global getPointerToNamedFunction(), which allows 242/// bugpoint or gdb users to search for a function by name without any context. 243class JitPool { 244 SmallPtrSet<JIT*, 1> JITs; // Optimize for process containing just 1 JIT. 245 mutable sys::Mutex Lock; 246public: 247 void Add(JIT *jit) { 248 MutexGuard guard(Lock); 249 JITs.insert(jit); 250 } 251 void Remove(JIT *jit) { 252 MutexGuard guard(Lock); 253 JITs.erase(jit); 254 } 255 void *getPointerToNamedFunction(const char *Name) const { 256 MutexGuard guard(Lock); 257 assert(JITs.size() != 0 && "No Jit registered"); 258 //search function in every instance of JIT 259 for (SmallPtrSet<JIT*, 1>::const_iterator Jit = JITs.begin(), 260 end = JITs.end(); 261 Jit != end; ++Jit) { 262 if (Function *F = (*Jit)->FindFunctionNamed(Name)) 263 return (*Jit)->getPointerToFunction(F); 264 } 265 // The function is not available : fallback on the first created (will 266 // search in symbol of the current program/library) 267 return (*JITs.begin())->getPointerToNamedFunction(Name); 268 } 269}; 270ManagedStatic<JitPool> AllJits; 271} 272extern "C" { 273 // getPointerToNamedFunction - This function is used as a global wrapper to 274 // JIT::getPointerToNamedFunction for the purpose of resolving symbols when 275 // bugpoint is debugging the JIT. In that scenario, we are loading an .so and 276 // need to resolve function(s) that are being mis-codegenerated, so we need to 277 // resolve their addresses at runtime, and this is the way to do it. 278 void *getPointerToNamedFunction(const char *Name) { 279 return AllJits->getPointerToNamedFunction(Name); 280 } 281} 282 283JIT::JIT(Module *M, TargetMachine &tm, TargetJITInfo &tji, 284 JITMemoryManager *JMM, CodeGenOpt::Level OptLevel, bool GVsWithCode) 285 : ExecutionEngine(M), TM(tm), TJI(tji), AllocateGVsWithCode(GVsWithCode), 286 isAlreadyCodeGenerating(false) { 287 setTargetData(TM.getTargetData()); 288 289 jitstate = new JITState(M); 290 291 // Initialize JCE 292 JCE = createEmitter(*this, JMM, TM); 293 294 // Register in global list of all JITs. 295 AllJits->Add(this); 296 297 // Add target data 298 MutexGuard locked(lock); 299 FunctionPassManager &PM = jitstate->getPM(locked); 300 PM.add(new TargetData(*TM.getTargetData())); 301 302 // Turn the machine code intermediate representation into bytes in memory that 303 // may be executed. 304 if (TM.addPassesToEmitMachineCode(PM, *JCE, OptLevel)) { 305 report_fatal_error("Target does not support machine code emission!"); 306 } 307 308 // Register routine for informing unwinding runtime about new EH frames 309#if defined(__GNUC__) && !defined(__ARM_EABI__) && !defined(__USING_SJLJ_EXCEPTIONS__) 310#if USE_KEYMGR 311 struct LibgccObjectInfo* LOI = (struct LibgccObjectInfo*) 312 _keymgr_get_and_lock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST); 313 314 // The key is created on demand, and libgcc creates it the first time an 315 // exception occurs. Since we need the key to register frames, we create 316 // it now. 317 if (!LOI) 318 LOI = (LibgccObjectInfo*)calloc(sizeof(struct LibgccObjectInfo), 1); 319 _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST, LOI); 320 InstallExceptionTableRegister(DarwinRegisterFrame); 321#else 322 InstallExceptionTableRegister(__register_frame); 323#endif // __APPLE__ 324#endif // __GNUC__ 325 326 // Initialize passes. 327 PM.doInitialization(); 328} 329 330JIT::~JIT() { 331 AllJits->Remove(this); 332 delete jitstate; 333 delete JCE; 334 delete &TM; 335} 336 337/// addModule - Add a new Module to the JIT. If we previously removed the last 338/// Module, we need re-initialize jitstate with a valid Module. 339void JIT::addModule(Module *M) { 340 MutexGuard locked(lock); 341 342 if (Modules.empty()) { 343 assert(!jitstate && "jitstate should be NULL if Modules vector is empty!"); 344 345 jitstate = new JITState(M); 346 347 FunctionPassManager &PM = jitstate->getPM(locked); 348 PM.add(new TargetData(*TM.getTargetData())); 349 350 // Turn the machine code intermediate representation into bytes in memory 351 // that may be executed. 352 if (TM.addPassesToEmitMachineCode(PM, *JCE, CodeGenOpt::Default)) { 353 report_fatal_error("Target does not support machine code emission!"); 354 } 355 356 // Initialize passes. 357 PM.doInitialization(); 358 } 359 360 ExecutionEngine::addModule(M); 361} 362 363/// removeModule - If we are removing the last Module, invalidate the jitstate 364/// since the PassManager it contains references a released Module. 365bool JIT::removeModule(Module *M) { 366 bool result = ExecutionEngine::removeModule(M); 367 368 MutexGuard locked(lock); 369 370 if (jitstate->getModule() == M) { 371 delete jitstate; 372 jitstate = 0; 373 } 374 375 if (!jitstate && !Modules.empty()) { 376 jitstate = new JITState(Modules[0]); 377 378 FunctionPassManager &PM = jitstate->getPM(locked); 379 PM.add(new TargetData(*TM.getTargetData())); 380 381 // Turn the machine code intermediate representation into bytes in memory 382 // that may be executed. 383 if (TM.addPassesToEmitMachineCode(PM, *JCE, CodeGenOpt::Default)) { 384 report_fatal_error("Target does not support machine code emission!"); 385 } 386 387 // Initialize passes. 388 PM.doInitialization(); 389 } 390 return result; 391} 392 393/// run - Start execution with the specified function and arguments. 394/// 395GenericValue JIT::runFunction(Function *F, 396 const std::vector<GenericValue> &ArgValues) { 397 assert(F && "Function *F was null at entry to run()"); 398 399 void *FPtr = getPointerToFunction(F); 400 assert(FPtr && "Pointer to fn's code was null after getPointerToFunction"); 401 const FunctionType *FTy = F->getFunctionType(); 402 const Type *RetTy = FTy->getReturnType(); 403 404 assert((FTy->getNumParams() == ArgValues.size() || 405 (FTy->isVarArg() && FTy->getNumParams() <= ArgValues.size())) && 406 "Wrong number of arguments passed into function!"); 407 assert(FTy->getNumParams() == ArgValues.size() && 408 "This doesn't support passing arguments through varargs (yet)!"); 409 410 // Handle some common cases first. These cases correspond to common `main' 411 // prototypes. 412 if (RetTy->isIntegerTy(32) || RetTy->isVoidTy()) { 413 switch (ArgValues.size()) { 414 case 3: 415 if (FTy->getParamType(0)->isIntegerTy(32) && 416 FTy->getParamType(1)->isPointerTy() && 417 FTy->getParamType(2)->isPointerTy()) { 418 int (*PF)(int, char **, const char **) = 419 (int(*)(int, char **, const char **))(intptr_t)FPtr; 420 421 // Call the function. 422 GenericValue rv; 423 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(), 424 (char **)GVTOP(ArgValues[1]), 425 (const char **)GVTOP(ArgValues[2]))); 426 return rv; 427 } 428 break; 429 case 2: 430 if (FTy->getParamType(0)->isIntegerTy(32) && 431 FTy->getParamType(1)->isPointerTy()) { 432 int (*PF)(int, char **) = (int(*)(int, char **))(intptr_t)FPtr; 433 434 // Call the function. 435 GenericValue rv; 436 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(), 437 (char **)GVTOP(ArgValues[1]))); 438 return rv; 439 } 440 break; 441 case 1: 442 if (FTy->getNumParams() == 1 && 443 FTy->getParamType(0)->isIntegerTy(32)) { 444 GenericValue rv; 445 int (*PF)(int) = (int(*)(int))(intptr_t)FPtr; 446 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue())); 447 return rv; 448 } 449 break; 450 } 451 } 452 453 // Handle cases where no arguments are passed first. 454 if (ArgValues.empty()) { 455 GenericValue rv; 456 switch (RetTy->getTypeID()) { 457 default: llvm_unreachable("Unknown return type for function call!"); 458 case Type::IntegerTyID: { 459 unsigned BitWidth = cast<IntegerType>(RetTy)->getBitWidth(); 460 if (BitWidth == 1) 461 rv.IntVal = APInt(BitWidth, ((bool(*)())(intptr_t)FPtr)()); 462 else if (BitWidth <= 8) 463 rv.IntVal = APInt(BitWidth, ((char(*)())(intptr_t)FPtr)()); 464 else if (BitWidth <= 16) 465 rv.IntVal = APInt(BitWidth, ((short(*)())(intptr_t)FPtr)()); 466 else if (BitWidth <= 32) 467 rv.IntVal = APInt(BitWidth, ((int(*)())(intptr_t)FPtr)()); 468 else if (BitWidth <= 64) 469 rv.IntVal = APInt(BitWidth, ((int64_t(*)())(intptr_t)FPtr)()); 470 else 471 llvm_unreachable("Integer types > 64 bits not supported"); 472 return rv; 473 } 474 case Type::VoidTyID: 475 rv.IntVal = APInt(32, ((int(*)())(intptr_t)FPtr)()); 476 return rv; 477 case Type::FloatTyID: 478 rv.FloatVal = ((float(*)())(intptr_t)FPtr)(); 479 return rv; 480 case Type::DoubleTyID: 481 rv.DoubleVal = ((double(*)())(intptr_t)FPtr)(); 482 return rv; 483 case Type::X86_FP80TyID: 484 case Type::FP128TyID: 485 case Type::PPC_FP128TyID: 486 llvm_unreachable("long double not supported yet"); 487 return rv; 488 case Type::PointerTyID: 489 return PTOGV(((void*(*)())(intptr_t)FPtr)()); 490 } 491 } 492 493 // Okay, this is not one of our quick and easy cases. Because we don't have a 494 // full FFI, we have to codegen a nullary stub function that just calls the 495 // function we are interested in, passing in constants for all of the 496 // arguments. Make this function and return. 497 498 // First, create the function. 499 FunctionType *STy=FunctionType::get(RetTy, false); 500 Function *Stub = Function::Create(STy, Function::InternalLinkage, "", 501 F->getParent()); 502 503 // Insert a basic block. 504 BasicBlock *StubBB = BasicBlock::Create(F->getContext(), "", Stub); 505 506 // Convert all of the GenericValue arguments over to constants. Note that we 507 // currently don't support varargs. 508 SmallVector<Value*, 8> Args; 509 for (unsigned i = 0, e = ArgValues.size(); i != e; ++i) { 510 Constant *C = 0; 511 const Type *ArgTy = FTy->getParamType(i); 512 const GenericValue &AV = ArgValues[i]; 513 switch (ArgTy->getTypeID()) { 514 default: llvm_unreachable("Unknown argument type for function call!"); 515 case Type::IntegerTyID: 516 C = ConstantInt::get(F->getContext(), AV.IntVal); 517 break; 518 case Type::FloatTyID: 519 C = ConstantFP::get(F->getContext(), APFloat(AV.FloatVal)); 520 break; 521 case Type::DoubleTyID: 522 C = ConstantFP::get(F->getContext(), APFloat(AV.DoubleVal)); 523 break; 524 case Type::PPC_FP128TyID: 525 case Type::X86_FP80TyID: 526 case Type::FP128TyID: 527 C = ConstantFP::get(F->getContext(), APFloat(AV.IntVal)); 528 break; 529 case Type::PointerTyID: 530 void *ArgPtr = GVTOP(AV); 531 if (sizeof(void*) == 4) 532 C = ConstantInt::get(Type::getInt32Ty(F->getContext()), 533 (int)(intptr_t)ArgPtr); 534 else 535 C = ConstantInt::get(Type::getInt64Ty(F->getContext()), 536 (intptr_t)ArgPtr); 537 // Cast the integer to pointer 538 C = ConstantExpr::getIntToPtr(C, ArgTy); 539 break; 540 } 541 Args.push_back(C); 542 } 543 544 CallInst *TheCall = CallInst::Create(F, Args.begin(), Args.end(), 545 "", StubBB); 546 TheCall->setCallingConv(F->getCallingConv()); 547 TheCall->setTailCall(); 548 if (!TheCall->getType()->isVoidTy()) 549 // Return result of the call. 550 ReturnInst::Create(F->getContext(), TheCall, StubBB); 551 else 552 ReturnInst::Create(F->getContext(), StubBB); // Just return void. 553 554 // Finally, call our nullary stub function. 555 GenericValue Result = runFunction(Stub, std::vector<GenericValue>()); 556 // Erase it, since no other function can have a reference to it. 557 Stub->eraseFromParent(); 558 // And return the result. 559 return Result; 560} 561 562void JIT::RegisterJITEventListener(JITEventListener *L) { 563 if (L == NULL) 564 return; 565 MutexGuard locked(lock); 566 EventListeners.push_back(L); 567} 568void JIT::UnregisterJITEventListener(JITEventListener *L) { 569 if (L == NULL) 570 return; 571 MutexGuard locked(lock); 572 std::vector<JITEventListener*>::reverse_iterator I= 573 std::find(EventListeners.rbegin(), EventListeners.rend(), L); 574 if (I != EventListeners.rend()) { 575 std::swap(*I, EventListeners.back()); 576 EventListeners.pop_back(); 577 } 578} 579void JIT::NotifyFunctionEmitted( 580 const Function &F, 581 void *Code, size_t Size, 582 const JITEvent_EmittedFunctionDetails &Details) { 583 MutexGuard locked(lock); 584 for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) { 585 EventListeners[I]->NotifyFunctionEmitted(F, Code, Size, Details); 586 } 587} 588 589void JIT::NotifyFreeingMachineCode(void *OldPtr) { 590 MutexGuard locked(lock); 591 for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) { 592 EventListeners[I]->NotifyFreeingMachineCode(OldPtr); 593 } 594} 595 596/// runJITOnFunction - Run the FunctionPassManager full of 597/// just-in-time compilation passes on F, hopefully filling in 598/// GlobalAddress[F] with the address of F's machine code. 599/// 600void JIT::runJITOnFunction(Function *F, MachineCodeInfo *MCI) { 601 MutexGuard locked(lock); 602 603 class MCIListener : public JITEventListener { 604 MachineCodeInfo *const MCI; 605 public: 606 MCIListener(MachineCodeInfo *mci) : MCI(mci) {} 607 virtual void NotifyFunctionEmitted(const Function &, 608 void *Code, size_t Size, 609 const EmittedFunctionDetails &) { 610 MCI->setAddress(Code); 611 MCI->setSize(Size); 612 } 613 }; 614 MCIListener MCIL(MCI); 615 if (MCI) 616 RegisterJITEventListener(&MCIL); 617 618 runJITOnFunctionUnlocked(F, locked); 619 620 if (MCI) 621 UnregisterJITEventListener(&MCIL); 622} 623 624void JIT::runJITOnFunctionUnlocked(Function *F, const MutexGuard &locked) { 625 assert(!isAlreadyCodeGenerating && "Error: Recursive compilation detected!"); 626 627 jitTheFunction(F, locked); 628 629 // If the function referred to another function that had not yet been 630 // read from bitcode, and we are jitting non-lazily, emit it now. 631 while (!jitstate->getPendingFunctions(locked).empty()) { 632 Function *PF = jitstate->getPendingFunctions(locked).back(); 633 jitstate->getPendingFunctions(locked).pop_back(); 634 635 assert(!PF->hasAvailableExternallyLinkage() && 636 "Externally-defined function should not be in pending list."); 637 638 jitTheFunction(PF, locked); 639 640 // Now that the function has been jitted, ask the JITEmitter to rewrite 641 // the stub with real address of the function. 642 updateFunctionStub(PF); 643 } 644} 645 646void JIT::jitTheFunction(Function *F, const MutexGuard &locked) { 647 isAlreadyCodeGenerating = true; 648 jitstate->getPM(locked).run(*F); 649 isAlreadyCodeGenerating = false; 650 651 // clear basic block addresses after this function is done 652 getBasicBlockAddressMap(locked).clear(); 653} 654 655/// getPointerToFunction - This method is used to get the address of the 656/// specified function, compiling it if neccesary. 657/// 658void *JIT::getPointerToFunction(Function *F) { 659 660 if (void *Addr = getPointerToGlobalIfAvailable(F)) 661 return Addr; // Check if function already code gen'd 662 663 MutexGuard locked(lock); 664 665 // Now that this thread owns the lock, make sure we read in the function if it 666 // exists in this Module. 667 std::string ErrorMsg; 668 if (F->Materialize(&ErrorMsg)) { 669 report_fatal_error("Error reading function '" + F->getName()+ 670 "' from bitcode file: " + ErrorMsg); 671 } 672 673 // ... and check if another thread has already code gen'd the function. 674 if (void *Addr = getPointerToGlobalIfAvailable(F)) 675 return Addr; 676 677 if (F->isDeclaration() || F->hasAvailableExternallyLinkage()) { 678 bool AbortOnFailure = !F->hasExternalWeakLinkage(); 679 void *Addr = getPointerToNamedFunction(F->getName(), AbortOnFailure); 680 addGlobalMapping(F, Addr); 681 return Addr; 682 } 683 684 runJITOnFunctionUnlocked(F, locked); 685 686 void *Addr = getPointerToGlobalIfAvailable(F); 687 assert(Addr && "Code generation didn't add function to GlobalAddress table!"); 688 return Addr; 689} 690 691void JIT::addPointerToBasicBlock(const BasicBlock *BB, void *Addr) { 692 MutexGuard locked(lock); 693 694 BasicBlockAddressMapTy::iterator I = 695 getBasicBlockAddressMap(locked).find(BB); 696 if (I == getBasicBlockAddressMap(locked).end()) { 697 getBasicBlockAddressMap(locked)[BB] = Addr; 698 } else { 699 // ignore repeats: some BBs can be split into few MBBs? 700 } 701} 702 703void JIT::clearPointerToBasicBlock(const BasicBlock *BB) { 704 MutexGuard locked(lock); 705 getBasicBlockAddressMap(locked).erase(BB); 706} 707 708void *JIT::getPointerToBasicBlock(BasicBlock *BB) { 709 // make sure it's function is compiled by JIT 710 (void)getPointerToFunction(BB->getParent()); 711 712 // resolve basic block address 713 MutexGuard locked(lock); 714 715 BasicBlockAddressMapTy::iterator I = 716 getBasicBlockAddressMap(locked).find(BB); 717 if (I != getBasicBlockAddressMap(locked).end()) { 718 return I->second; 719 } else { 720 assert(0 && "JIT does not have BB address for address-of-label, was" 721 " it eliminated by optimizer?"); 722 return 0; 723 } 724} 725 726/// getOrEmitGlobalVariable - Return the address of the specified global 727/// variable, possibly emitting it to memory if needed. This is used by the 728/// Emitter. 729void *JIT::getOrEmitGlobalVariable(const GlobalVariable *GV) { 730 MutexGuard locked(lock); 731 732 void *Ptr = getPointerToGlobalIfAvailable(GV); 733 if (Ptr) return Ptr; 734 735 // If the global is external, just remember the address. 736 if (GV->isDeclaration() || GV->hasAvailableExternallyLinkage()) { 737#if HAVE___DSO_HANDLE 738 if (GV->getName() == "__dso_handle") 739 return (void*)&__dso_handle; 740#endif 741 Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(GV->getName()); 742 if (Ptr == 0) { 743 report_fatal_error("Could not resolve external global address: " 744 +GV->getName()); 745 } 746 addGlobalMapping(GV, Ptr); 747 } else { 748 // If the global hasn't been emitted to memory yet, allocate space and 749 // emit it into memory. 750 Ptr = getMemoryForGV(GV); 751 addGlobalMapping(GV, Ptr); 752 EmitGlobalVariable(GV); // Initialize the variable. 753 } 754 return Ptr; 755} 756 757/// recompileAndRelinkFunction - This method is used to force a function 758/// which has already been compiled, to be compiled again, possibly 759/// after it has been modified. Then the entry to the old copy is overwritten 760/// with a branch to the new copy. If there was no old copy, this acts 761/// just like JIT::getPointerToFunction(). 762/// 763void *JIT::recompileAndRelinkFunction(Function *F) { 764 void *OldAddr = getPointerToGlobalIfAvailable(F); 765 766 // If it's not already compiled there is no reason to patch it up. 767 if (OldAddr == 0) { return getPointerToFunction(F); } 768 769 // Delete the old function mapping. 770 addGlobalMapping(F, 0); 771 772 // Recodegen the function 773 runJITOnFunction(F); 774 775 // Update state, forward the old function to the new function. 776 void *Addr = getPointerToGlobalIfAvailable(F); 777 assert(Addr && "Code generation didn't add function to GlobalAddress table!"); 778 TJI.replaceMachineCodeForFunction(OldAddr, Addr); 779 return Addr; 780} 781 782/// getMemoryForGV - This method abstracts memory allocation of global 783/// variable so that the JIT can allocate thread local variables depending 784/// on the target. 785/// 786char* JIT::getMemoryForGV(const GlobalVariable* GV) { 787 char *Ptr; 788 789 // GlobalVariable's which are not "constant" will cause trouble in a server 790 // situation. It's returned in the same block of memory as code which may 791 // not be writable. 792 if (isGVCompilationDisabled() && !GV->isConstant()) { 793 report_fatal_error("Compilation of non-internal GlobalValue is disabled!"); 794 } 795 796 // Some applications require globals and code to live together, so they may 797 // be allocated into the same buffer, but in general globals are allocated 798 // through the memory manager which puts them near the code but not in the 799 // same buffer. 800 const Type *GlobalType = GV->getType()->getElementType(); 801 size_t S = getTargetData()->getTypeAllocSize(GlobalType); 802 size_t A = getTargetData()->getPreferredAlignment(GV); 803 if (GV->isThreadLocal()) { 804 MutexGuard locked(lock); 805 Ptr = TJI.allocateThreadLocalMemory(S); 806 } else if (TJI.allocateSeparateGVMemory()) { 807 if (A <= 8) { 808 Ptr = (char*)malloc(S); 809 } else { 810 // Allocate S+A bytes of memory, then use an aligned pointer within that 811 // space. 812 Ptr = (char*)malloc(S+A); 813 unsigned MisAligned = ((intptr_t)Ptr & (A-1)); 814 Ptr = Ptr + (MisAligned ? (A-MisAligned) : 0); 815 } 816 } else if (AllocateGVsWithCode) { 817 Ptr = (char*)JCE->allocateSpace(S, A); 818 } else { 819 Ptr = (char*)JCE->allocateGlobal(S, A); 820 } 821 return Ptr; 822} 823 824void JIT::addPendingFunction(Function *F) { 825 MutexGuard locked(lock); 826 jitstate->getPendingFunctions(locked).push_back(F); 827} 828 829 830JITEventListener::~JITEventListener() {} 831