JIT.cpp revision 858143816d43e58b17bfd11cb1b57afbd7f0f893
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/Support/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// 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 76 77#if HAVE_EHTABLE_SUPPORT 78 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. 85// 86// The __register_frame function works with Linux. 87// 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. 95 96extern "C" void __register_frame(void*); 97extern "C" void __deregister_frame(void*); 98 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 104 105#if USE_KEYMGR 106 107namespace { 108 109// 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. 112struct LibgccObject { 113 void *unused1; 114 void *unused2; 115 void *unused3; 116 117 /// frame - Pointer to the exception table. 118 void *frame; 119 120 /// 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; 131 132 /// 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; 135 136 /// next - At least we know it's a chained list! 137 struct LibgccObject *next; 138}; 139 140// "kemgr" stuff. Apparently, all frame tables are stored there. 141extern "C" void _keymgr_set_and_unlock_processwide_ptr(int, void *); 142extern "C" void *_keymgr_get_and_lock_processwide_ptr(int); 143#define KEYMGR_GCC3_DW2_OBJ_LIST 302 /* Dwarf2 object list */ 144 145/// LibgccObjectInfo - libgcc defines this struct as km_object_info. It 146/// probably contains all dwarf tables that are loaded. 147struct LibgccObjectInfo { 148 149 /// seenObjects - LibgccObjects already parsed by the unwinding runtime. 150 /// 151 struct LibgccObject* seenObjects; 152 153 /// unseenObjects - LibgccObjects not parsed yet by the unwinding runtime. 154 /// 155 struct LibgccObject* unseenObjects; 156 157 unsigned unused[2]; 158}; 159 160/// 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. 163void 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"); 168 169 // 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)); 175 176 // 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; 183 184 // 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; 189 190 // Update the key's unseenObjects list. 191 LOI->unseenObjects = ob; 192 193 // Finally update the "key". Apparently, libgcc requires it. 194 _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST, 195 LOI); 196 197} 198 199} 200#endif // __APPLE__ 201#endif // HAVE_EHTABLE_SUPPORT 202 203/// 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. 206ExecutionEngine *JIT::createJIT(Module *M, 207 std::string *ErrorStr, 208 JITMemoryManager *JMM, 209 bool GVsWithCode, 210 TargetMachine *TM) { 211 // Try to register the program as a source of symbols to resolve against. 212 // 213 // FIXME: Don't do this here. 214 sys::DynamicLibrary::LoadLibraryPermanently(0, NULL); 215 216 // If the target supports JIT code generation, create the JIT. 217 if (TargetJITInfo *TJ = TM->getJITInfo()) { 218 return new JIT(M, *TM, *TJ, JMM, GVsWithCode); 219 } else { 220 if (ErrorStr) 221 *ErrorStr = "target does not support JIT code generation"; 222 return 0; 223 } 224} 225 226namespace { 227/// This class supports the global getPointerToNamedFunction(), which allows 228/// bugpoint or gdb users to search for a function by name without any context. 229class JitPool { 230 SmallPtrSet<JIT*, 1> JITs; // Optimize for process containing just 1 JIT. 231 mutable sys::Mutex Lock; 232public: 233 void Add(JIT *jit) { 234 MutexGuard guard(Lock); 235 JITs.insert(jit); 236 } 237 void Remove(JIT *jit) { 238 MutexGuard guard(Lock); 239 JITs.erase(jit); 240 } 241 void *getPointerToNamedFunction(const char *Name) const { 242 MutexGuard guard(Lock); 243 assert(JITs.size() != 0 && "No Jit registered"); 244 //search function in every instance of JIT 245 for (SmallPtrSet<JIT*, 1>::const_iterator Jit = JITs.begin(), 246 end = JITs.end(); 247 Jit != end; ++Jit) { 248 if (Function *F = (*Jit)->FindFunctionNamed(Name)) 249 return (*Jit)->getPointerToFunction(F); 250 } 251 // The function is not available : fallback on the first created (will 252 // search in symbol of the current program/library) 253 return (*JITs.begin())->getPointerToNamedFunction(Name); 254 } 255}; 256ManagedStatic<JitPool> AllJits; 257} 258extern "C" { 259 // getPointerToNamedFunction - This function is used as a global wrapper to 260 // JIT::getPointerToNamedFunction for the purpose of resolving symbols when 261 // bugpoint is debugging the JIT. In that scenario, we are loading an .so and 262 // need to resolve function(s) that are being mis-codegenerated, so we need to 263 // resolve their addresses at runtime, and this is the way to do it. 264 void *getPointerToNamedFunction(const char *Name) { 265 return AllJits->getPointerToNamedFunction(Name); 266 } 267} 268 269JIT::JIT(Module *M, TargetMachine &tm, TargetJITInfo &tji, 270 JITMemoryManager *JMM, bool GVsWithCode) 271 : ExecutionEngine(M), TM(tm), TJI(tji), AllocateGVsWithCode(GVsWithCode), 272 isAlreadyCodeGenerating(false) { 273 setTargetData(TM.getTargetData()); 274 275 jitstate = new JITState(M); 276 277 // Initialize JCE 278 JCE = createEmitter(*this, JMM, TM); 279 280 // Register in global list of all JITs. 281 AllJits->Add(this); 282 283 // Add target data 284 MutexGuard locked(lock); 285 FunctionPassManager &PM = jitstate->getPM(locked); 286 PM.add(new TargetData(*TM.getTargetData())); 287 288 // Turn the machine code intermediate representation into bytes in memory that 289 // may be executed. 290 if (TM.addPassesToEmitMachineCode(PM, *JCE)) { 291 report_fatal_error("Target does not support machine code emission!"); 292 } 293 294 // Register routine for informing unwinding runtime about new EH frames 295#if HAVE_EHTABLE_SUPPORT 296#if USE_KEYMGR 297 struct LibgccObjectInfo* LOI = (struct LibgccObjectInfo*) 298 _keymgr_get_and_lock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST); 299 300 // The key is created on demand, and libgcc creates it the first time an 301 // exception occurs. Since we need the key to register frames, we create 302 // it now. 303 if (!LOI) 304 LOI = (LibgccObjectInfo*)calloc(sizeof(struct LibgccObjectInfo), 1); 305 _keymgr_set_and_unlock_processwide_ptr(KEYMGR_GCC3_DW2_OBJ_LIST, LOI); 306 InstallExceptionTableRegister(DarwinRegisterFrame); 307 // Not sure about how to deregister on Darwin. 308#else 309 InstallExceptionTableRegister(__register_frame); 310 InstallExceptionTableDeregister(__deregister_frame); 311#endif // __APPLE__ 312#endif // HAVE_EHTABLE_SUPPORT 313 314 // Initialize passes. 315 PM.doInitialization(); 316} 317 318JIT::~JIT() { 319 // Unregister all exception tables registered by this JIT. 320 DeregisterAllTables(); 321 // Cleanup. 322 AllJits->Remove(this); 323 delete jitstate; 324 delete JCE; 325 delete &TM; 326} 327 328/// addModule - Add a new Module to the JIT. If we previously removed the last 329/// Module, we need re-initialize jitstate with a valid Module. 330void JIT::addModule(Module *M) { 331 MutexGuard locked(lock); 332 333 if (Modules.empty()) { 334 assert(!jitstate && "jitstate should be NULL if Modules vector is empty!"); 335 336 jitstate = new JITState(M); 337 338 FunctionPassManager &PM = jitstate->getPM(locked); 339 PM.add(new TargetData(*TM.getTargetData())); 340 341 // Turn the machine code intermediate representation into bytes in memory 342 // that may be executed. 343 if (TM.addPassesToEmitMachineCode(PM, *JCE)) { 344 report_fatal_error("Target does not support machine code emission!"); 345 } 346 347 // Initialize passes. 348 PM.doInitialization(); 349 } 350 351 ExecutionEngine::addModule(M); 352} 353 354/// removeModule - If we are removing the last Module, invalidate the jitstate 355/// since the PassManager it contains references a released Module. 356bool JIT::removeModule(Module *M) { 357 bool result = ExecutionEngine::removeModule(M); 358 359 MutexGuard locked(lock); 360 361 if (jitstate->getModule() == M) { 362 delete jitstate; 363 jitstate = 0; 364 } 365 366 if (!jitstate && !Modules.empty()) { 367 jitstate = new JITState(Modules[0]); 368 369 FunctionPassManager &PM = jitstate->getPM(locked); 370 PM.add(new TargetData(*TM.getTargetData())); 371 372 // Turn the machine code intermediate representation into bytes in memory 373 // that may be executed. 374 if (TM.addPassesToEmitMachineCode(PM, *JCE)) { 375 report_fatal_error("Target does not support machine code emission!"); 376 } 377 378 // Initialize passes. 379 PM.doInitialization(); 380 } 381 return result; 382} 383 384/// run - Start execution with the specified function and arguments. 385/// 386GenericValue JIT::runFunction(Function *F, 387 const std::vector<GenericValue> &ArgValues) { 388 assert(F && "Function *F was null at entry to run()"); 389 390 void *FPtr = getPointerToFunction(F); 391 assert(FPtr && "Pointer to fn's code was null after getPointerToFunction"); 392 FunctionType *FTy = F->getFunctionType(); 393 Type *RetTy = FTy->getReturnType(); 394 395 assert((FTy->getNumParams() == ArgValues.size() || 396 (FTy->isVarArg() && FTy->getNumParams() <= ArgValues.size())) && 397 "Wrong number of arguments passed into function!"); 398 assert(FTy->getNumParams() == ArgValues.size() && 399 "This doesn't support passing arguments through varargs (yet)!"); 400 401 // Handle some common cases first. These cases correspond to common `main' 402 // prototypes. 403 if (RetTy->isIntegerTy(32) || RetTy->isVoidTy()) { 404 switch (ArgValues.size()) { 405 case 3: 406 if (FTy->getParamType(0)->isIntegerTy(32) && 407 FTy->getParamType(1)->isPointerTy() && 408 FTy->getParamType(2)->isPointerTy()) { 409 int (*PF)(int, char **, const char **) = 410 (int(*)(int, char **, const char **))(intptr_t)FPtr; 411 412 // Call the function. 413 GenericValue rv; 414 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(), 415 (char **)GVTOP(ArgValues[1]), 416 (const char **)GVTOP(ArgValues[2]))); 417 return rv; 418 } 419 break; 420 case 2: 421 if (FTy->getParamType(0)->isIntegerTy(32) && 422 FTy->getParamType(1)->isPointerTy()) { 423 int (*PF)(int, char **) = (int(*)(int, char **))(intptr_t)FPtr; 424 425 // Call the function. 426 GenericValue rv; 427 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(), 428 (char **)GVTOP(ArgValues[1]))); 429 return rv; 430 } 431 break; 432 case 1: 433 if (FTy->getNumParams() == 1 && 434 FTy->getParamType(0)->isIntegerTy(32)) { 435 GenericValue rv; 436 int (*PF)(int) = (int(*)(int))(intptr_t)FPtr; 437 rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue())); 438 return rv; 439 } 440 break; 441 } 442 } 443 444 // Handle cases where no arguments are passed first. 445 if (ArgValues.empty()) { 446 GenericValue rv; 447 switch (RetTy->getTypeID()) { 448 default: llvm_unreachable("Unknown return type for function call!"); 449 case Type::IntegerTyID: { 450 unsigned BitWidth = cast<IntegerType>(RetTy)->getBitWidth(); 451 if (BitWidth == 1) 452 rv.IntVal = APInt(BitWidth, ((bool(*)())(intptr_t)FPtr)()); 453 else if (BitWidth <= 8) 454 rv.IntVal = APInt(BitWidth, ((char(*)())(intptr_t)FPtr)()); 455 else if (BitWidth <= 16) 456 rv.IntVal = APInt(BitWidth, ((short(*)())(intptr_t)FPtr)()); 457 else if (BitWidth <= 32) 458 rv.IntVal = APInt(BitWidth, ((int(*)())(intptr_t)FPtr)()); 459 else if (BitWidth <= 64) 460 rv.IntVal = APInt(BitWidth, ((int64_t(*)())(intptr_t)FPtr)()); 461 else 462 llvm_unreachable("Integer types > 64 bits not supported"); 463 return rv; 464 } 465 case Type::VoidTyID: 466 rv.IntVal = APInt(32, ((int(*)())(intptr_t)FPtr)()); 467 return rv; 468 case Type::FloatTyID: 469 rv.FloatVal = ((float(*)())(intptr_t)FPtr)(); 470 return rv; 471 case Type::DoubleTyID: 472 rv.DoubleVal = ((double(*)())(intptr_t)FPtr)(); 473 return rv; 474 case Type::X86_FP80TyID: 475 case Type::FP128TyID: 476 case Type::PPC_FP128TyID: 477 llvm_unreachable("long double not supported yet"); 478 case Type::PointerTyID: 479 return PTOGV(((void*(*)())(intptr_t)FPtr)()); 480 } 481 } 482 483 // Okay, this is not one of our quick and easy cases. Because we don't have a 484 // full FFI, we have to codegen a nullary stub function that just calls the 485 // function we are interested in, passing in constants for all of the 486 // arguments. Make this function and return. 487 488 // First, create the function. 489 FunctionType *STy=FunctionType::get(RetTy, false); 490 Function *Stub = Function::Create(STy, Function::InternalLinkage, "", 491 F->getParent()); 492 493 // Insert a basic block. 494 BasicBlock *StubBB = BasicBlock::Create(F->getContext(), "", Stub); 495 496 // Convert all of the GenericValue arguments over to constants. Note that we 497 // currently don't support varargs. 498 SmallVector<Value*, 8> Args; 499 for (unsigned i = 0, e = ArgValues.size(); i != e; ++i) { 500 Constant *C = 0; 501 Type *ArgTy = FTy->getParamType(i); 502 const GenericValue &AV = ArgValues[i]; 503 switch (ArgTy->getTypeID()) { 504 default: llvm_unreachable("Unknown argument type for function call!"); 505 case Type::IntegerTyID: 506 C = ConstantInt::get(F->getContext(), AV.IntVal); 507 break; 508 case Type::FloatTyID: 509 C = ConstantFP::get(F->getContext(), APFloat(AV.FloatVal)); 510 break; 511 case Type::DoubleTyID: 512 C = ConstantFP::get(F->getContext(), APFloat(AV.DoubleVal)); 513 break; 514 case Type::PPC_FP128TyID: 515 case Type::X86_FP80TyID: 516 case Type::FP128TyID: 517 C = ConstantFP::get(F->getContext(), APFloat(AV.IntVal)); 518 break; 519 case Type::PointerTyID: 520 void *ArgPtr = GVTOP(AV); 521 if (sizeof(void*) == 4) 522 C = ConstantInt::get(Type::getInt32Ty(F->getContext()), 523 (int)(intptr_t)ArgPtr); 524 else 525 C = ConstantInt::get(Type::getInt64Ty(F->getContext()), 526 (intptr_t)ArgPtr); 527 // Cast the integer to pointer 528 C = ConstantExpr::getIntToPtr(C, ArgTy); 529 break; 530 } 531 Args.push_back(C); 532 } 533 534 CallInst *TheCall = CallInst::Create(F, Args, "", StubBB); 535 TheCall->setCallingConv(F->getCallingConv()); 536 TheCall->setTailCall(); 537 if (!TheCall->getType()->isVoidTy()) 538 // Return result of the call. 539 ReturnInst::Create(F->getContext(), TheCall, StubBB); 540 else 541 ReturnInst::Create(F->getContext(), StubBB); // Just return void. 542 543 // Finally, call our nullary stub function. 544 GenericValue Result = runFunction(Stub, std::vector<GenericValue>()); 545 // Erase it, since no other function can have a reference to it. 546 Stub->eraseFromParent(); 547 // And return the result. 548 return Result; 549} 550 551void JIT::RegisterJITEventListener(JITEventListener *L) { 552 if (L == NULL) 553 return; 554 MutexGuard locked(lock); 555 EventListeners.push_back(L); 556} 557void JIT::UnregisterJITEventListener(JITEventListener *L) { 558 if (L == NULL) 559 return; 560 MutexGuard locked(lock); 561 std::vector<JITEventListener*>::reverse_iterator I= 562 std::find(EventListeners.rbegin(), EventListeners.rend(), L); 563 if (I != EventListeners.rend()) { 564 std::swap(*I, EventListeners.back()); 565 EventListeners.pop_back(); 566 } 567} 568void JIT::NotifyFunctionEmitted( 569 const Function &F, 570 void *Code, size_t Size, 571 const JITEvent_EmittedFunctionDetails &Details) { 572 MutexGuard locked(lock); 573 for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) { 574 EventListeners[I]->NotifyFunctionEmitted(F, Code, Size, Details); 575 } 576} 577 578void JIT::NotifyFreeingMachineCode(void *OldPtr) { 579 MutexGuard locked(lock); 580 for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) { 581 EventListeners[I]->NotifyFreeingMachineCode(OldPtr); 582 } 583} 584 585/// runJITOnFunction - Run the FunctionPassManager full of 586/// just-in-time compilation passes on F, hopefully filling in 587/// GlobalAddress[F] with the address of F's machine code. 588/// 589void JIT::runJITOnFunction(Function *F, MachineCodeInfo *MCI) { 590 MutexGuard locked(lock); 591 592 class MCIListener : public JITEventListener { 593 MachineCodeInfo *const MCI; 594 public: 595 MCIListener(MachineCodeInfo *mci) : MCI(mci) {} 596 virtual void NotifyFunctionEmitted(const Function &, 597 void *Code, size_t Size, 598 const EmittedFunctionDetails &) { 599 MCI->setAddress(Code); 600 MCI->setSize(Size); 601 } 602 }; 603 MCIListener MCIL(MCI); 604 if (MCI) 605 RegisterJITEventListener(&MCIL); 606 607 runJITOnFunctionUnlocked(F, locked); 608 609 if (MCI) 610 UnregisterJITEventListener(&MCIL); 611} 612 613void JIT::runJITOnFunctionUnlocked(Function *F, const MutexGuard &locked) { 614 assert(!isAlreadyCodeGenerating && "Error: Recursive compilation detected!"); 615 616 jitTheFunction(F, locked); 617 618 // If the function referred to another function that had not yet been 619 // read from bitcode, and we are jitting non-lazily, emit it now. 620 while (!jitstate->getPendingFunctions(locked).empty()) { 621 Function *PF = jitstate->getPendingFunctions(locked).back(); 622 jitstate->getPendingFunctions(locked).pop_back(); 623 624 assert(!PF->hasAvailableExternallyLinkage() && 625 "Externally-defined function should not be in pending list."); 626 627 jitTheFunction(PF, locked); 628 629 // Now that the function has been jitted, ask the JITEmitter to rewrite 630 // the stub with real address of the function. 631 updateFunctionStub(PF); 632 } 633} 634 635void JIT::jitTheFunction(Function *F, const MutexGuard &locked) { 636 isAlreadyCodeGenerating = true; 637 jitstate->getPM(locked).run(*F); 638 isAlreadyCodeGenerating = false; 639 640 // clear basic block addresses after this function is done 641 getBasicBlockAddressMap(locked).clear(); 642} 643 644/// getPointerToFunction - This method is used to get the address of the 645/// specified function, compiling it if necessary. 646/// 647void *JIT::getPointerToFunction(Function *F) { 648 649 if (void *Addr = getPointerToGlobalIfAvailable(F)) 650 return Addr; // Check if function already code gen'd 651 652 MutexGuard locked(lock); 653 654 // Now that this thread owns the lock, make sure we read in the function if it 655 // exists in this Module. 656 std::string ErrorMsg; 657 if (F->Materialize(&ErrorMsg)) { 658 report_fatal_error("Error reading function '" + F->getName()+ 659 "' from bitcode file: " + ErrorMsg); 660 } 661 662 // ... and check if another thread has already code gen'd the function. 663 if (void *Addr = getPointerToGlobalIfAvailable(F)) 664 return Addr; 665 666 if (F->isDeclaration() || F->hasAvailableExternallyLinkage()) { 667 bool AbortOnFailure = !F->hasExternalWeakLinkage(); 668 void *Addr = getPointerToNamedFunction(F->getName(), AbortOnFailure); 669 addGlobalMapping(F, Addr); 670 return Addr; 671 } 672 673 runJITOnFunctionUnlocked(F, locked); 674 675 void *Addr = getPointerToGlobalIfAvailable(F); 676 assert(Addr && "Code generation didn't add function to GlobalAddress table!"); 677 return Addr; 678} 679 680void JIT::addPointerToBasicBlock(const BasicBlock *BB, void *Addr) { 681 MutexGuard locked(lock); 682 683 BasicBlockAddressMapTy::iterator I = 684 getBasicBlockAddressMap(locked).find(BB); 685 if (I == getBasicBlockAddressMap(locked).end()) { 686 getBasicBlockAddressMap(locked)[BB] = Addr; 687 } else { 688 // ignore repeats: some BBs can be split into few MBBs? 689 } 690} 691 692void JIT::clearPointerToBasicBlock(const BasicBlock *BB) { 693 MutexGuard locked(lock); 694 getBasicBlockAddressMap(locked).erase(BB); 695} 696 697void *JIT::getPointerToBasicBlock(BasicBlock *BB) { 698 // make sure it's function is compiled by JIT 699 (void)getPointerToFunction(BB->getParent()); 700 701 // resolve basic block address 702 MutexGuard locked(lock); 703 704 BasicBlockAddressMapTy::iterator I = 705 getBasicBlockAddressMap(locked).find(BB); 706 if (I != getBasicBlockAddressMap(locked).end()) { 707 return I->second; 708 } else { 709 llvm_unreachable("JIT does not have BB address for address-of-label, was" 710 " it eliminated by optimizer?"); 711 } 712} 713 714/// getOrEmitGlobalVariable - Return the address of the specified global 715/// variable, possibly emitting it to memory if needed. This is used by the 716/// Emitter. 717void *JIT::getOrEmitGlobalVariable(const GlobalVariable *GV) { 718 MutexGuard locked(lock); 719 720 void *Ptr = getPointerToGlobalIfAvailable(GV); 721 if (Ptr) return Ptr; 722 723 // If the global is external, just remember the address. 724 if (GV->isDeclaration() || GV->hasAvailableExternallyLinkage()) { 725#if HAVE___DSO_HANDLE 726 if (GV->getName() == "__dso_handle") 727 return (void*)&__dso_handle; 728#endif 729 Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(GV->getName()); 730 if (Ptr == 0) { 731 report_fatal_error("Could not resolve external global address: " 732 +GV->getName()); 733 } 734 addGlobalMapping(GV, Ptr); 735 } else { 736 // If the global hasn't been emitted to memory yet, allocate space and 737 // emit it into memory. 738 Ptr = getMemoryForGV(GV); 739 addGlobalMapping(GV, Ptr); 740 EmitGlobalVariable(GV); // Initialize the variable. 741 } 742 return Ptr; 743} 744 745/// recompileAndRelinkFunction - This method is used to force a function 746/// which has already been compiled, to be compiled again, possibly 747/// after it has been modified. Then the entry to the old copy is overwritten 748/// with a branch to the new copy. If there was no old copy, this acts 749/// just like JIT::getPointerToFunction(). 750/// 751void *JIT::recompileAndRelinkFunction(Function *F) { 752 void *OldAddr = getPointerToGlobalIfAvailable(F); 753 754 // If it's not already compiled there is no reason to patch it up. 755 if (OldAddr == 0) { return getPointerToFunction(F); } 756 757 // Delete the old function mapping. 758 addGlobalMapping(F, 0); 759 760 // Recodegen the function 761 runJITOnFunction(F); 762 763 // Update state, forward the old function to the new function. 764 void *Addr = getPointerToGlobalIfAvailable(F); 765 assert(Addr && "Code generation didn't add function to GlobalAddress table!"); 766 TJI.replaceMachineCodeForFunction(OldAddr, Addr); 767 return Addr; 768} 769 770/// getMemoryForGV - This method abstracts memory allocation of global 771/// variable so that the JIT can allocate thread local variables depending 772/// on the target. 773/// 774char* JIT::getMemoryForGV(const GlobalVariable* GV) { 775 char *Ptr; 776 777 // GlobalVariable's which are not "constant" will cause trouble in a server 778 // situation. It's returned in the same block of memory as code which may 779 // not be writable. 780 if (isGVCompilationDisabled() && !GV->isConstant()) { 781 report_fatal_error("Compilation of non-internal GlobalValue is disabled!"); 782 } 783 784 // Some applications require globals and code to live together, so they may 785 // be allocated into the same buffer, but in general globals are allocated 786 // through the memory manager which puts them near the code but not in the 787 // same buffer. 788 Type *GlobalType = GV->getType()->getElementType(); 789 size_t S = getTargetData()->getTypeAllocSize(GlobalType); 790 size_t A = getTargetData()->getPreferredAlignment(GV); 791 if (GV->isThreadLocal()) { 792 MutexGuard locked(lock); 793 Ptr = TJI.allocateThreadLocalMemory(S); 794 } else if (TJI.allocateSeparateGVMemory()) { 795 if (A <= 8) { 796 Ptr = (char*)malloc(S); 797 } else { 798 // Allocate S+A bytes of memory, then use an aligned pointer within that 799 // space. 800 Ptr = (char*)malloc(S+A); 801 unsigned MisAligned = ((intptr_t)Ptr & (A-1)); 802 Ptr = Ptr + (MisAligned ? (A-MisAligned) : 0); 803 } 804 } else if (AllocateGVsWithCode) { 805 Ptr = (char*)JCE->allocateSpace(S, A); 806 } else { 807 Ptr = (char*)JCE->allocateGlobal(S, A); 808 } 809 return Ptr; 810} 811 812void JIT::addPendingFunction(Function *F) { 813 MutexGuard locked(lock); 814 jitstate->getPendingFunctions(locked).push_back(F); 815} 816 817 818JITEventListener::~JITEventListener() {} 819