ThreadSanitizer.cpp revision 36b56886974eae4f9c5ebc96befd3e7bfe5de338
1//===-- ThreadSanitizer.cpp - race detector -------------------------------===// 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 file is a part of ThreadSanitizer, a race detector. 11// 12// The tool is under development, for the details about previous versions see 13// http://code.google.com/p/data-race-test 14// 15// The instrumentation phase is quite simple: 16// - Insert calls to run-time library before every memory access. 17// - Optimizations may apply to avoid instrumenting some of the accesses. 18// - Insert calls at function entry/exit. 19// The rest is handled by the run-time library. 20//===----------------------------------------------------------------------===// 21 22#define DEBUG_TYPE "tsan" 23 24#include "llvm/Transforms/Instrumentation.h" 25#include "llvm/ADT/SmallSet.h" 26#include "llvm/ADT/SmallString.h" 27#include "llvm/ADT/SmallVector.h" 28#include "llvm/ADT/Statistic.h" 29#include "llvm/ADT/StringExtras.h" 30#include "llvm/IR/DataLayout.h" 31#include "llvm/IR/Function.h" 32#include "llvm/IR/IRBuilder.h" 33#include "llvm/IR/IntrinsicInst.h" 34#include "llvm/IR/Intrinsics.h" 35#include "llvm/IR/LLVMContext.h" 36#include "llvm/IR/Metadata.h" 37#include "llvm/IR/Module.h" 38#include "llvm/IR/Type.h" 39#include "llvm/Support/CommandLine.h" 40#include "llvm/Support/Debug.h" 41#include "llvm/Support/MathExtras.h" 42#include "llvm/Support/raw_ostream.h" 43#include "llvm/Transforms/Utils/BasicBlockUtils.h" 44#include "llvm/Transforms/Utils/ModuleUtils.h" 45#include "llvm/Transforms/Utils/SpecialCaseList.h" 46 47using namespace llvm; 48 49static cl::opt<std::string> ClBlacklistFile("tsan-blacklist", 50 cl::desc("Blacklist file"), cl::Hidden); 51static cl::opt<bool> ClInstrumentMemoryAccesses( 52 "tsan-instrument-memory-accesses", cl::init(true), 53 cl::desc("Instrument memory accesses"), cl::Hidden); 54static cl::opt<bool> ClInstrumentFuncEntryExit( 55 "tsan-instrument-func-entry-exit", cl::init(true), 56 cl::desc("Instrument function entry and exit"), cl::Hidden); 57static cl::opt<bool> ClInstrumentAtomics( 58 "tsan-instrument-atomics", cl::init(true), 59 cl::desc("Instrument atomics"), cl::Hidden); 60static cl::opt<bool> ClInstrumentMemIntrinsics( 61 "tsan-instrument-memintrinsics", cl::init(true), 62 cl::desc("Instrument memintrinsics (memset/memcpy/memmove)"), cl::Hidden); 63 64STATISTIC(NumInstrumentedReads, "Number of instrumented reads"); 65STATISTIC(NumInstrumentedWrites, "Number of instrumented writes"); 66STATISTIC(NumOmittedReadsBeforeWrite, 67 "Number of reads ignored due to following writes"); 68STATISTIC(NumAccessesWithBadSize, "Number of accesses with bad size"); 69STATISTIC(NumInstrumentedVtableWrites, "Number of vtable ptr writes"); 70STATISTIC(NumInstrumentedVtableReads, "Number of vtable ptr reads"); 71STATISTIC(NumOmittedReadsFromConstantGlobals, 72 "Number of reads from constant globals"); 73STATISTIC(NumOmittedReadsFromVtable, "Number of vtable reads"); 74 75namespace { 76 77/// ThreadSanitizer: instrument the code in module to find races. 78struct ThreadSanitizer : public FunctionPass { 79 ThreadSanitizer(StringRef BlacklistFile = StringRef()) 80 : FunctionPass(ID), 81 DL(0), 82 BlacklistFile(BlacklistFile.empty() ? ClBlacklistFile 83 : BlacklistFile) { } 84 const char *getPassName() const override; 85 bool runOnFunction(Function &F) override; 86 bool doInitialization(Module &M) override; 87 static char ID; // Pass identification, replacement for typeid. 88 89 private: 90 void initializeCallbacks(Module &M); 91 bool instrumentLoadOrStore(Instruction *I); 92 bool instrumentAtomic(Instruction *I); 93 bool instrumentMemIntrinsic(Instruction *I); 94 void chooseInstructionsToInstrument(SmallVectorImpl<Instruction*> &Local, 95 SmallVectorImpl<Instruction*> &All); 96 bool addrPointsToConstantData(Value *Addr); 97 int getMemoryAccessFuncIndex(Value *Addr); 98 99 const DataLayout *DL; 100 Type *IntptrTy; 101 SmallString<64> BlacklistFile; 102 std::unique_ptr<SpecialCaseList> BL; 103 IntegerType *OrdTy; 104 // Callbacks to run-time library are computed in doInitialization. 105 Function *TsanFuncEntry; 106 Function *TsanFuncExit; 107 // Accesses sizes are powers of two: 1, 2, 4, 8, 16. 108 static const size_t kNumberOfAccessSizes = 5; 109 Function *TsanRead[kNumberOfAccessSizes]; 110 Function *TsanWrite[kNumberOfAccessSizes]; 111 Function *TsanAtomicLoad[kNumberOfAccessSizes]; 112 Function *TsanAtomicStore[kNumberOfAccessSizes]; 113 Function *TsanAtomicRMW[AtomicRMWInst::LAST_BINOP + 1][kNumberOfAccessSizes]; 114 Function *TsanAtomicCAS[kNumberOfAccessSizes]; 115 Function *TsanAtomicThreadFence; 116 Function *TsanAtomicSignalFence; 117 Function *TsanVptrUpdate; 118 Function *TsanVptrLoad; 119 Function *MemmoveFn, *MemcpyFn, *MemsetFn; 120}; 121} // namespace 122 123char ThreadSanitizer::ID = 0; 124INITIALIZE_PASS(ThreadSanitizer, "tsan", 125 "ThreadSanitizer: detects data races.", 126 false, false) 127 128const char *ThreadSanitizer::getPassName() const { 129 return "ThreadSanitizer"; 130} 131 132FunctionPass *llvm::createThreadSanitizerPass(StringRef BlacklistFile) { 133 return new ThreadSanitizer(BlacklistFile); 134} 135 136static Function *checkInterfaceFunction(Constant *FuncOrBitcast) { 137 if (Function *F = dyn_cast<Function>(FuncOrBitcast)) 138 return F; 139 FuncOrBitcast->dump(); 140 report_fatal_error("ThreadSanitizer interface function redefined"); 141} 142 143void ThreadSanitizer::initializeCallbacks(Module &M) { 144 IRBuilder<> IRB(M.getContext()); 145 // Initialize the callbacks. 146 TsanFuncEntry = checkInterfaceFunction(M.getOrInsertFunction( 147 "__tsan_func_entry", IRB.getVoidTy(), IRB.getInt8PtrTy(), NULL)); 148 TsanFuncExit = checkInterfaceFunction(M.getOrInsertFunction( 149 "__tsan_func_exit", IRB.getVoidTy(), NULL)); 150 OrdTy = IRB.getInt32Ty(); 151 for (size_t i = 0; i < kNumberOfAccessSizes; ++i) { 152 const size_t ByteSize = 1 << i; 153 const size_t BitSize = ByteSize * 8; 154 SmallString<32> ReadName("__tsan_read" + itostr(ByteSize)); 155 TsanRead[i] = checkInterfaceFunction(M.getOrInsertFunction( 156 ReadName, IRB.getVoidTy(), IRB.getInt8PtrTy(), NULL)); 157 158 SmallString<32> WriteName("__tsan_write" + itostr(ByteSize)); 159 TsanWrite[i] = checkInterfaceFunction(M.getOrInsertFunction( 160 WriteName, IRB.getVoidTy(), IRB.getInt8PtrTy(), NULL)); 161 162 Type *Ty = Type::getIntNTy(M.getContext(), BitSize); 163 Type *PtrTy = Ty->getPointerTo(); 164 SmallString<32> AtomicLoadName("__tsan_atomic" + itostr(BitSize) + 165 "_load"); 166 TsanAtomicLoad[i] = checkInterfaceFunction(M.getOrInsertFunction( 167 AtomicLoadName, Ty, PtrTy, OrdTy, NULL)); 168 169 SmallString<32> AtomicStoreName("__tsan_atomic" + itostr(BitSize) + 170 "_store"); 171 TsanAtomicStore[i] = checkInterfaceFunction(M.getOrInsertFunction( 172 AtomicStoreName, IRB.getVoidTy(), PtrTy, Ty, OrdTy, 173 NULL)); 174 175 for (int op = AtomicRMWInst::FIRST_BINOP; 176 op <= AtomicRMWInst::LAST_BINOP; ++op) { 177 TsanAtomicRMW[op][i] = NULL; 178 const char *NamePart = NULL; 179 if (op == AtomicRMWInst::Xchg) 180 NamePart = "_exchange"; 181 else if (op == AtomicRMWInst::Add) 182 NamePart = "_fetch_add"; 183 else if (op == AtomicRMWInst::Sub) 184 NamePart = "_fetch_sub"; 185 else if (op == AtomicRMWInst::And) 186 NamePart = "_fetch_and"; 187 else if (op == AtomicRMWInst::Or) 188 NamePart = "_fetch_or"; 189 else if (op == AtomicRMWInst::Xor) 190 NamePart = "_fetch_xor"; 191 else if (op == AtomicRMWInst::Nand) 192 NamePart = "_fetch_nand"; 193 else 194 continue; 195 SmallString<32> RMWName("__tsan_atomic" + itostr(BitSize) + NamePart); 196 TsanAtomicRMW[op][i] = checkInterfaceFunction(M.getOrInsertFunction( 197 RMWName, Ty, PtrTy, Ty, OrdTy, NULL)); 198 } 199 200 SmallString<32> AtomicCASName("__tsan_atomic" + itostr(BitSize) + 201 "_compare_exchange_val"); 202 TsanAtomicCAS[i] = checkInterfaceFunction(M.getOrInsertFunction( 203 AtomicCASName, Ty, PtrTy, Ty, Ty, OrdTy, OrdTy, NULL)); 204 } 205 TsanVptrUpdate = checkInterfaceFunction(M.getOrInsertFunction( 206 "__tsan_vptr_update", IRB.getVoidTy(), IRB.getInt8PtrTy(), 207 IRB.getInt8PtrTy(), NULL)); 208 TsanVptrLoad = checkInterfaceFunction(M.getOrInsertFunction( 209 "__tsan_vptr_read", IRB.getVoidTy(), IRB.getInt8PtrTy(), NULL)); 210 TsanAtomicThreadFence = checkInterfaceFunction(M.getOrInsertFunction( 211 "__tsan_atomic_thread_fence", IRB.getVoidTy(), OrdTy, NULL)); 212 TsanAtomicSignalFence = checkInterfaceFunction(M.getOrInsertFunction( 213 "__tsan_atomic_signal_fence", IRB.getVoidTy(), OrdTy, NULL)); 214 215 MemmoveFn = checkInterfaceFunction(M.getOrInsertFunction( 216 "memmove", IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), 217 IRB.getInt8PtrTy(), IntptrTy, NULL)); 218 MemcpyFn = checkInterfaceFunction(M.getOrInsertFunction( 219 "memcpy", IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), 220 IntptrTy, NULL)); 221 MemsetFn = checkInterfaceFunction(M.getOrInsertFunction( 222 "memset", IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), IRB.getInt32Ty(), 223 IntptrTy, NULL)); 224} 225 226bool ThreadSanitizer::doInitialization(Module &M) { 227 DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>(); 228 if (!DLP) 229 return false; 230 DL = &DLP->getDataLayout(); 231 BL.reset(SpecialCaseList::createOrDie(BlacklistFile)); 232 233 // Always insert a call to __tsan_init into the module's CTORs. 234 IRBuilder<> IRB(M.getContext()); 235 IntptrTy = IRB.getIntPtrTy(DL); 236 Value *TsanInit = M.getOrInsertFunction("__tsan_init", 237 IRB.getVoidTy(), NULL); 238 appendToGlobalCtors(M, cast<Function>(TsanInit), 0); 239 240 return true; 241} 242 243static bool isVtableAccess(Instruction *I) { 244 if (MDNode *Tag = I->getMetadata(LLVMContext::MD_tbaa)) 245 return Tag->isTBAAVtableAccess(); 246 return false; 247} 248 249bool ThreadSanitizer::addrPointsToConstantData(Value *Addr) { 250 // If this is a GEP, just analyze its pointer operand. 251 if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Addr)) 252 Addr = GEP->getPointerOperand(); 253 254 if (GlobalVariable *GV = dyn_cast<GlobalVariable>(Addr)) { 255 if (GV->isConstant()) { 256 // Reads from constant globals can not race with any writes. 257 NumOmittedReadsFromConstantGlobals++; 258 return true; 259 } 260 } else if (LoadInst *L = dyn_cast<LoadInst>(Addr)) { 261 if (isVtableAccess(L)) { 262 // Reads from a vtable pointer can not race with any writes. 263 NumOmittedReadsFromVtable++; 264 return true; 265 } 266 } 267 return false; 268} 269 270// Instrumenting some of the accesses may be proven redundant. 271// Currently handled: 272// - read-before-write (within same BB, no calls between) 273// 274// We do not handle some of the patterns that should not survive 275// after the classic compiler optimizations. 276// E.g. two reads from the same temp should be eliminated by CSE, 277// two writes should be eliminated by DSE, etc. 278// 279// 'Local' is a vector of insns within the same BB (no calls between). 280// 'All' is a vector of insns that will be instrumented. 281void ThreadSanitizer::chooseInstructionsToInstrument( 282 SmallVectorImpl<Instruction*> &Local, 283 SmallVectorImpl<Instruction*> &All) { 284 SmallSet<Value*, 8> WriteTargets; 285 // Iterate from the end. 286 for (SmallVectorImpl<Instruction*>::reverse_iterator It = Local.rbegin(), 287 E = Local.rend(); It != E; ++It) { 288 Instruction *I = *It; 289 if (StoreInst *Store = dyn_cast<StoreInst>(I)) { 290 WriteTargets.insert(Store->getPointerOperand()); 291 } else { 292 LoadInst *Load = cast<LoadInst>(I); 293 Value *Addr = Load->getPointerOperand(); 294 if (WriteTargets.count(Addr)) { 295 // We will write to this temp, so no reason to analyze the read. 296 NumOmittedReadsBeforeWrite++; 297 continue; 298 } 299 if (addrPointsToConstantData(Addr)) { 300 // Addr points to some constant data -- it can not race with any writes. 301 continue; 302 } 303 } 304 All.push_back(I); 305 } 306 Local.clear(); 307} 308 309static bool isAtomic(Instruction *I) { 310 if (LoadInst *LI = dyn_cast<LoadInst>(I)) 311 return LI->isAtomic() && LI->getSynchScope() == CrossThread; 312 if (StoreInst *SI = dyn_cast<StoreInst>(I)) 313 return SI->isAtomic() && SI->getSynchScope() == CrossThread; 314 if (isa<AtomicRMWInst>(I)) 315 return true; 316 if (isa<AtomicCmpXchgInst>(I)) 317 return true; 318 if (isa<FenceInst>(I)) 319 return true; 320 return false; 321} 322 323bool ThreadSanitizer::runOnFunction(Function &F) { 324 if (!DL) return false; 325 if (BL->isIn(F)) return false; 326 initializeCallbacks(*F.getParent()); 327 SmallVector<Instruction*, 8> RetVec; 328 SmallVector<Instruction*, 8> AllLoadsAndStores; 329 SmallVector<Instruction*, 8> LocalLoadsAndStores; 330 SmallVector<Instruction*, 8> AtomicAccesses; 331 SmallVector<Instruction*, 8> MemIntrinCalls; 332 bool Res = false; 333 bool HasCalls = false; 334 335 // Traverse all instructions, collect loads/stores/returns, check for calls. 336 for (Function::iterator FI = F.begin(), FE = F.end(); 337 FI != FE; ++FI) { 338 BasicBlock &BB = *FI; 339 for (BasicBlock::iterator BI = BB.begin(), BE = BB.end(); 340 BI != BE; ++BI) { 341 if (isAtomic(BI)) 342 AtomicAccesses.push_back(BI); 343 else if (isa<LoadInst>(BI) || isa<StoreInst>(BI)) 344 LocalLoadsAndStores.push_back(BI); 345 else if (isa<ReturnInst>(BI)) 346 RetVec.push_back(BI); 347 else if (isa<CallInst>(BI) || isa<InvokeInst>(BI)) { 348 if (isa<MemIntrinsic>(BI)) 349 MemIntrinCalls.push_back(BI); 350 HasCalls = true; 351 chooseInstructionsToInstrument(LocalLoadsAndStores, AllLoadsAndStores); 352 } 353 } 354 chooseInstructionsToInstrument(LocalLoadsAndStores, AllLoadsAndStores); 355 } 356 357 // We have collected all loads and stores. 358 // FIXME: many of these accesses do not need to be checked for races 359 // (e.g. variables that do not escape, etc). 360 361 // Instrument memory accesses. 362 if (ClInstrumentMemoryAccesses && F.hasFnAttribute(Attribute::SanitizeThread)) 363 for (size_t i = 0, n = AllLoadsAndStores.size(); i < n; ++i) { 364 Res |= instrumentLoadOrStore(AllLoadsAndStores[i]); 365 } 366 367 // Instrument atomic memory accesses. 368 if (ClInstrumentAtomics) 369 for (size_t i = 0, n = AtomicAccesses.size(); i < n; ++i) { 370 Res |= instrumentAtomic(AtomicAccesses[i]); 371 } 372 373 if (ClInstrumentMemIntrinsics) 374 for (size_t i = 0, n = MemIntrinCalls.size(); i < n; ++i) { 375 Res |= instrumentMemIntrinsic(MemIntrinCalls[i]); 376 } 377 378 // Instrument function entry/exit points if there were instrumented accesses. 379 if ((Res || HasCalls) && ClInstrumentFuncEntryExit) { 380 IRBuilder<> IRB(F.getEntryBlock().getFirstNonPHI()); 381 Value *ReturnAddress = IRB.CreateCall( 382 Intrinsic::getDeclaration(F.getParent(), Intrinsic::returnaddress), 383 IRB.getInt32(0)); 384 IRB.CreateCall(TsanFuncEntry, ReturnAddress); 385 for (size_t i = 0, n = RetVec.size(); i < n; ++i) { 386 IRBuilder<> IRBRet(RetVec[i]); 387 IRBRet.CreateCall(TsanFuncExit); 388 } 389 Res = true; 390 } 391 return Res; 392} 393 394bool ThreadSanitizer::instrumentLoadOrStore(Instruction *I) { 395 IRBuilder<> IRB(I); 396 bool IsWrite = isa<StoreInst>(*I); 397 Value *Addr = IsWrite 398 ? cast<StoreInst>(I)->getPointerOperand() 399 : cast<LoadInst>(I)->getPointerOperand(); 400 int Idx = getMemoryAccessFuncIndex(Addr); 401 if (Idx < 0) 402 return false; 403 if (IsWrite && isVtableAccess(I)) { 404 DEBUG(dbgs() << " VPTR : " << *I << "\n"); 405 Value *StoredValue = cast<StoreInst>(I)->getValueOperand(); 406 // StoredValue may be a vector type if we are storing several vptrs at once. 407 // In this case, just take the first element of the vector since this is 408 // enough to find vptr races. 409 if (isa<VectorType>(StoredValue->getType())) 410 StoredValue = IRB.CreateExtractElement( 411 StoredValue, ConstantInt::get(IRB.getInt32Ty(), 0)); 412 if (StoredValue->getType()->isIntegerTy()) 413 StoredValue = IRB.CreateIntToPtr(StoredValue, IRB.getInt8PtrTy()); 414 // Call TsanVptrUpdate. 415 IRB.CreateCall2(TsanVptrUpdate, 416 IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy()), 417 IRB.CreatePointerCast(StoredValue, IRB.getInt8PtrTy())); 418 NumInstrumentedVtableWrites++; 419 return true; 420 } 421 if (!IsWrite && isVtableAccess(I)) { 422 IRB.CreateCall(TsanVptrLoad, 423 IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy())); 424 NumInstrumentedVtableReads++; 425 return true; 426 } 427 Value *OnAccessFunc = IsWrite ? TsanWrite[Idx] : TsanRead[Idx]; 428 IRB.CreateCall(OnAccessFunc, IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy())); 429 if (IsWrite) NumInstrumentedWrites++; 430 else NumInstrumentedReads++; 431 return true; 432} 433 434static ConstantInt *createOrdering(IRBuilder<> *IRB, AtomicOrdering ord) { 435 uint32_t v = 0; 436 switch (ord) { 437 case NotAtomic: assert(false); 438 case Unordered: // Fall-through. 439 case Monotonic: v = 0; break; 440 // case Consume: v = 1; break; // Not specified yet. 441 case Acquire: v = 2; break; 442 case Release: v = 3; break; 443 case AcquireRelease: v = 4; break; 444 case SequentiallyConsistent: v = 5; break; 445 } 446 return IRB->getInt32(v); 447} 448 449// If a memset intrinsic gets inlined by the code gen, we will miss races on it. 450// So, we either need to ensure the intrinsic is not inlined, or instrument it. 451// We do not instrument memset/memmove/memcpy intrinsics (too complicated), 452// instead we simply replace them with regular function calls, which are then 453// intercepted by the run-time. 454// Since tsan is running after everyone else, the calls should not be 455// replaced back with intrinsics. If that becomes wrong at some point, 456// we will need to call e.g. __tsan_memset to avoid the intrinsics. 457bool ThreadSanitizer::instrumentMemIntrinsic(Instruction *I) { 458 IRBuilder<> IRB(I); 459 if (MemSetInst *M = dyn_cast<MemSetInst>(I)) { 460 IRB.CreateCall3(MemsetFn, 461 IRB.CreatePointerCast(M->getArgOperand(0), IRB.getInt8PtrTy()), 462 IRB.CreateIntCast(M->getArgOperand(1), IRB.getInt32Ty(), false), 463 IRB.CreateIntCast(M->getArgOperand(2), IntptrTy, false)); 464 I->eraseFromParent(); 465 } else if (MemTransferInst *M = dyn_cast<MemTransferInst>(I)) { 466 IRB.CreateCall3(isa<MemCpyInst>(M) ? MemcpyFn : MemmoveFn, 467 IRB.CreatePointerCast(M->getArgOperand(0), IRB.getInt8PtrTy()), 468 IRB.CreatePointerCast(M->getArgOperand(1), IRB.getInt8PtrTy()), 469 IRB.CreateIntCast(M->getArgOperand(2), IntptrTy, false)); 470 I->eraseFromParent(); 471 } 472 return false; 473} 474 475// Both llvm and ThreadSanitizer atomic operations are based on C++11/C1x 476// standards. For background see C++11 standard. A slightly older, publicly 477// available draft of the standard (not entirely up-to-date, but close enough 478// for casual browsing) is available here: 479// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3242.pdf 480// The following page contains more background information: 481// http://www.hpl.hp.com/personal/Hans_Boehm/c++mm/ 482 483bool ThreadSanitizer::instrumentAtomic(Instruction *I) { 484 IRBuilder<> IRB(I); 485 if (LoadInst *LI = dyn_cast<LoadInst>(I)) { 486 Value *Addr = LI->getPointerOperand(); 487 int Idx = getMemoryAccessFuncIndex(Addr); 488 if (Idx < 0) 489 return false; 490 const size_t ByteSize = 1 << Idx; 491 const size_t BitSize = ByteSize * 8; 492 Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize); 493 Type *PtrTy = Ty->getPointerTo(); 494 Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy), 495 createOrdering(&IRB, LI->getOrdering())}; 496 CallInst *C = CallInst::Create(TsanAtomicLoad[Idx], 497 ArrayRef<Value*>(Args)); 498 ReplaceInstWithInst(I, C); 499 500 } else if (StoreInst *SI = dyn_cast<StoreInst>(I)) { 501 Value *Addr = SI->getPointerOperand(); 502 int Idx = getMemoryAccessFuncIndex(Addr); 503 if (Idx < 0) 504 return false; 505 const size_t ByteSize = 1 << Idx; 506 const size_t BitSize = ByteSize * 8; 507 Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize); 508 Type *PtrTy = Ty->getPointerTo(); 509 Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy), 510 IRB.CreateIntCast(SI->getValueOperand(), Ty, false), 511 createOrdering(&IRB, SI->getOrdering())}; 512 CallInst *C = CallInst::Create(TsanAtomicStore[Idx], 513 ArrayRef<Value*>(Args)); 514 ReplaceInstWithInst(I, C); 515 } else if (AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(I)) { 516 Value *Addr = RMWI->getPointerOperand(); 517 int Idx = getMemoryAccessFuncIndex(Addr); 518 if (Idx < 0) 519 return false; 520 Function *F = TsanAtomicRMW[RMWI->getOperation()][Idx]; 521 if (F == NULL) 522 return false; 523 const size_t ByteSize = 1 << Idx; 524 const size_t BitSize = ByteSize * 8; 525 Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize); 526 Type *PtrTy = Ty->getPointerTo(); 527 Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy), 528 IRB.CreateIntCast(RMWI->getValOperand(), Ty, false), 529 createOrdering(&IRB, RMWI->getOrdering())}; 530 CallInst *C = CallInst::Create(F, ArrayRef<Value*>(Args)); 531 ReplaceInstWithInst(I, C); 532 } else if (AtomicCmpXchgInst *CASI = dyn_cast<AtomicCmpXchgInst>(I)) { 533 Value *Addr = CASI->getPointerOperand(); 534 int Idx = getMemoryAccessFuncIndex(Addr); 535 if (Idx < 0) 536 return false; 537 const size_t ByteSize = 1 << Idx; 538 const size_t BitSize = ByteSize * 8; 539 Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize); 540 Type *PtrTy = Ty->getPointerTo(); 541 Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy), 542 IRB.CreateIntCast(CASI->getCompareOperand(), Ty, false), 543 IRB.CreateIntCast(CASI->getNewValOperand(), Ty, false), 544 createOrdering(&IRB, CASI->getSuccessOrdering()), 545 createOrdering(&IRB, CASI->getFailureOrdering())}; 546 CallInst *C = CallInst::Create(TsanAtomicCAS[Idx], ArrayRef<Value*>(Args)); 547 ReplaceInstWithInst(I, C); 548 } else if (FenceInst *FI = dyn_cast<FenceInst>(I)) { 549 Value *Args[] = {createOrdering(&IRB, FI->getOrdering())}; 550 Function *F = FI->getSynchScope() == SingleThread ? 551 TsanAtomicSignalFence : TsanAtomicThreadFence; 552 CallInst *C = CallInst::Create(F, ArrayRef<Value*>(Args)); 553 ReplaceInstWithInst(I, C); 554 } 555 return true; 556} 557 558int ThreadSanitizer::getMemoryAccessFuncIndex(Value *Addr) { 559 Type *OrigPtrTy = Addr->getType(); 560 Type *OrigTy = cast<PointerType>(OrigPtrTy)->getElementType(); 561 assert(OrigTy->isSized()); 562 uint32_t TypeSize = DL->getTypeStoreSizeInBits(OrigTy); 563 if (TypeSize != 8 && TypeSize != 16 && 564 TypeSize != 32 && TypeSize != 64 && TypeSize != 128) { 565 NumAccessesWithBadSize++; 566 // Ignore all unusual sizes. 567 return -1; 568 } 569 size_t Idx = countTrailingZeros(TypeSize / 8); 570 assert(Idx < kNumberOfAccessSizes); 571 return Idx; 572} 573