1 //===-- ThreadSanitizer.cpp - race detector -------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file is a part of ThreadSanitizer, a race detector.
12 // The tool is under development, for the details about previous versions see
13 // http://code.google.com/p/data-race-test
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 //===----------------------------------------------------------------------===//
22 #define DEBUG_TYPE "tsan"
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/BlackList.h"
45 #include "llvm/Transforms/Utils/ModuleUtils.h"
49 static cl::opt<std::string> ClBlacklistFile("tsan-blacklist",
50 cl::desc("Blacklist file"), cl::Hidden);
51 static cl::opt<bool> ClInstrumentMemoryAccesses(
52 "tsan-instrument-memory-accesses", cl::init(true),
53 cl::desc("Instrument memory accesses"), cl::Hidden);
54 static cl::opt<bool> ClInstrumentFuncEntryExit(
55 "tsan-instrument-func-entry-exit", cl::init(true),
56 cl::desc("Instrument function entry and exit"), cl::Hidden);
57 static cl::opt<bool> ClInstrumentAtomics(
58 "tsan-instrument-atomics", cl::init(true),
59 cl::desc("Instrument atomics"), cl::Hidden);
60 static cl::opt<bool> ClInstrumentMemIntrinsics(
61 "tsan-instrument-memintrinsics", cl::init(true),
62 cl::desc("Instrument memintrinsics (memset/memcpy/memmove)"), cl::Hidden);
64 STATISTIC(NumInstrumentedReads, "Number of instrumented reads");
65 STATISTIC(NumInstrumentedWrites, "Number of instrumented writes");
66 STATISTIC(NumOmittedReadsBeforeWrite,
67 "Number of reads ignored due to following writes");
68 STATISTIC(NumAccessesWithBadSize, "Number of accesses with bad size");
69 STATISTIC(NumInstrumentedVtableWrites, "Number of vtable ptr writes");
70 STATISTIC(NumInstrumentedVtableReads, "Number of vtable ptr reads");
71 STATISTIC(NumOmittedReadsFromConstantGlobals,
72 "Number of reads from constant globals");
73 STATISTIC(NumOmittedReadsFromVtable, "Number of vtable reads");
77 /// ThreadSanitizer: instrument the code in module to find races.
78 struct ThreadSanitizer : public FunctionPass {
79 ThreadSanitizer(StringRef BlacklistFile = StringRef())
82 BlacklistFile(BlacklistFile.empty() ? ClBlacklistFile
84 const char *getPassName() const;
85 bool runOnFunction(Function &F);
86 bool doInitialization(Module &M);
87 static char ID; // Pass identification, replacement for typeid.
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);
101 SmallString<64> BlacklistFile;
102 OwningPtr<BlackList> BL;
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;
123 char ThreadSanitizer::ID = 0;
124 INITIALIZE_PASS(ThreadSanitizer, "tsan",
125 "ThreadSanitizer: detects data races.",
128 const char *ThreadSanitizer::getPassName() const {
129 return "ThreadSanitizer";
132 FunctionPass *llvm::createThreadSanitizerPass(StringRef BlacklistFile) {
133 return new ThreadSanitizer(BlacklistFile);
136 static Function *checkInterfaceFunction(Constant *FuncOrBitcast) {
137 if (Function *F = dyn_cast<Function>(FuncOrBitcast))
139 FuncOrBitcast->dump();
140 report_fatal_error("ThreadSanitizer interface function redefined");
143 void 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));
158 SmallString<32> WriteName("__tsan_write" + itostr(ByteSize));
159 TsanWrite[i] = checkInterfaceFunction(M.getOrInsertFunction(
160 WriteName, IRB.getVoidTy(), IRB.getInt8PtrTy(), NULL));
162 Type *Ty = Type::getIntNTy(M.getContext(), BitSize);
163 Type *PtrTy = Ty->getPointerTo();
164 SmallString<32> AtomicLoadName("__tsan_atomic" + itostr(BitSize) +
166 TsanAtomicLoad[i] = checkInterfaceFunction(M.getOrInsertFunction(
167 AtomicLoadName, Ty, PtrTy, OrdTy, NULL));
169 SmallString<32> AtomicStoreName("__tsan_atomic" + itostr(BitSize) +
171 TsanAtomicStore[i] = checkInterfaceFunction(M.getOrInsertFunction(
172 AtomicStoreName, IRB.getVoidTy(), PtrTy, Ty, OrdTy,
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";
195 SmallString<32> RMWName("__tsan_atomic" + itostr(BitSize) + NamePart);
196 TsanAtomicRMW[op][i] = checkInterfaceFunction(M.getOrInsertFunction(
197 RMWName, Ty, PtrTy, Ty, OrdTy, NULL));
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));
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));
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(),
221 MemsetFn = checkInterfaceFunction(M.getOrInsertFunction(
222 "memset", IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), IRB.getInt32Ty(),
226 bool ThreadSanitizer::doInitialization(Module &M) {
227 TD = getAnalysisIfAvailable<DataLayout>();
230 BL.reset(new BlackList(BlacklistFile));
232 // Always insert a call to __tsan_init into the module's CTORs.
233 IRBuilder<> IRB(M.getContext());
234 IntptrTy = IRB.getIntPtrTy(TD);
235 Value *TsanInit = M.getOrInsertFunction("__tsan_init",
236 IRB.getVoidTy(), NULL);
237 appendToGlobalCtors(M, cast<Function>(TsanInit), 0);
242 static bool isVtableAccess(Instruction *I) {
243 if (MDNode *Tag = I->getMetadata(LLVMContext::MD_tbaa)) {
244 if (Tag->getNumOperands() < 1) return false;
245 if (MDString *Tag1 = dyn_cast<MDString>(Tag->getOperand(0))) {
246 if (Tag1->getString() == "vtable pointer") return true;
252 bool ThreadSanitizer::addrPointsToConstantData(Value *Addr) {
253 // If this is a GEP, just analyze its pointer operand.
254 if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Addr))
255 Addr = GEP->getPointerOperand();
257 if (GlobalVariable *GV = dyn_cast<GlobalVariable>(Addr)) {
258 if (GV->isConstant()) {
259 // Reads from constant globals can not race with any writes.
260 NumOmittedReadsFromConstantGlobals++;
263 } else if (LoadInst *L = dyn_cast<LoadInst>(Addr)) {
264 if (isVtableAccess(L)) {
265 // Reads from a vtable pointer can not race with any writes.
266 NumOmittedReadsFromVtable++;
273 // Instrumenting some of the accesses may be proven redundant.
274 // Currently handled:
275 // - read-before-write (within same BB, no calls between)
277 // We do not handle some of the patterns that should not survive
278 // after the classic compiler optimizations.
279 // E.g. two reads from the same temp should be eliminated by CSE,
280 // two writes should be eliminated by DSE, etc.
282 // 'Local' is a vector of insns within the same BB (no calls between).
283 // 'All' is a vector of insns that will be instrumented.
284 void ThreadSanitizer::chooseInstructionsToInstrument(
285 SmallVectorImpl<Instruction*> &Local,
286 SmallVectorImpl<Instruction*> &All) {
287 SmallSet<Value*, 8> WriteTargets;
288 // Iterate from the end.
289 for (SmallVectorImpl<Instruction*>::reverse_iterator It = Local.rbegin(),
290 E = Local.rend(); It != E; ++It) {
291 Instruction *I = *It;
292 if (StoreInst *Store = dyn_cast<StoreInst>(I)) {
293 WriteTargets.insert(Store->getPointerOperand());
295 LoadInst *Load = cast<LoadInst>(I);
296 Value *Addr = Load->getPointerOperand();
297 if (WriteTargets.count(Addr)) {
298 // We will write to this temp, so no reason to analyze the read.
299 NumOmittedReadsBeforeWrite++;
302 if (addrPointsToConstantData(Addr)) {
303 // Addr points to some constant data -- it can not race with any writes.
312 static bool isAtomic(Instruction *I) {
313 if (LoadInst *LI = dyn_cast<LoadInst>(I))
314 return LI->isAtomic() && LI->getSynchScope() == CrossThread;
315 if (StoreInst *SI = dyn_cast<StoreInst>(I))
316 return SI->isAtomic() && SI->getSynchScope() == CrossThread;
317 if (isa<AtomicRMWInst>(I))
319 if (isa<AtomicCmpXchgInst>(I))
321 if (isa<FenceInst>(I))
326 bool ThreadSanitizer::runOnFunction(Function &F) {
327 if (!TD) return false;
328 if (BL->isIn(F)) return false;
329 initializeCallbacks(*F.getParent());
330 SmallVector<Instruction*, 8> RetVec;
331 SmallVector<Instruction*, 8> AllLoadsAndStores;
332 SmallVector<Instruction*, 8> LocalLoadsAndStores;
333 SmallVector<Instruction*, 8> AtomicAccesses;
334 SmallVector<Instruction*, 8> MemIntrinCalls;
336 bool HasCalls = false;
338 // Traverse all instructions, collect loads/stores/returns, check for calls.
339 for (Function::iterator FI = F.begin(), FE = F.end();
341 BasicBlock &BB = *FI;
342 for (BasicBlock::iterator BI = BB.begin(), BE = BB.end();
345 AtomicAccesses.push_back(BI);
346 else if (isa<LoadInst>(BI) || isa<StoreInst>(BI))
347 LocalLoadsAndStores.push_back(BI);
348 else if (isa<ReturnInst>(BI))
349 RetVec.push_back(BI);
350 else if (isa<CallInst>(BI) || isa<InvokeInst>(BI)) {
351 if (isa<MemIntrinsic>(BI))
352 MemIntrinCalls.push_back(BI);
354 chooseInstructionsToInstrument(LocalLoadsAndStores, AllLoadsAndStores);
357 chooseInstructionsToInstrument(LocalLoadsAndStores, AllLoadsAndStores);
360 // We have collected all loads and stores.
361 // FIXME: many of these accesses do not need to be checked for races
362 // (e.g. variables that do not escape, etc).
364 // Instrument memory accesses.
365 if (ClInstrumentMemoryAccesses)
366 for (size_t i = 0, n = AllLoadsAndStores.size(); i < n; ++i) {
367 Res |= instrumentLoadOrStore(AllLoadsAndStores[i]);
370 // Instrument atomic memory accesses.
371 if (ClInstrumentAtomics)
372 for (size_t i = 0, n = AtomicAccesses.size(); i < n; ++i) {
373 Res |= instrumentAtomic(AtomicAccesses[i]);
376 if (ClInstrumentMemIntrinsics)
377 for (size_t i = 0, n = MemIntrinCalls.size(); i < n; ++i) {
378 Res |= instrumentMemIntrinsic(MemIntrinCalls[i]);
381 // Instrument function entry/exit points if there were instrumented accesses.
382 if ((Res || HasCalls) && ClInstrumentFuncEntryExit) {
383 IRBuilder<> IRB(F.getEntryBlock().getFirstNonPHI());
384 Value *ReturnAddress = IRB.CreateCall(
385 Intrinsic::getDeclaration(F.getParent(), Intrinsic::returnaddress),
387 IRB.CreateCall(TsanFuncEntry, ReturnAddress);
388 for (size_t i = 0, n = RetVec.size(); i < n; ++i) {
389 IRBuilder<> IRBRet(RetVec[i]);
390 IRBRet.CreateCall(TsanFuncExit);
397 bool ThreadSanitizer::instrumentLoadOrStore(Instruction *I) {
399 bool IsWrite = isa<StoreInst>(*I);
400 Value *Addr = IsWrite
401 ? cast<StoreInst>(I)->getPointerOperand()
402 : cast<LoadInst>(I)->getPointerOperand();
403 int Idx = getMemoryAccessFuncIndex(Addr);
406 if (IsWrite && isVtableAccess(I)) {
407 DEBUG(dbgs() << " VPTR : " << *I << "\n");
408 Value *StoredValue = cast<StoreInst>(I)->getValueOperand();
409 // StoredValue does not necessary have a pointer type.
410 if (isa<IntegerType>(StoredValue->getType()))
411 StoredValue = IRB.CreateIntToPtr(StoredValue, IRB.getInt8PtrTy());
412 // Call TsanVptrUpdate.
413 IRB.CreateCall2(TsanVptrUpdate,
414 IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy()),
415 IRB.CreatePointerCast(StoredValue, IRB.getInt8PtrTy()));
416 NumInstrumentedVtableWrites++;
419 if (!IsWrite && isVtableAccess(I)) {
420 IRB.CreateCall(TsanVptrLoad,
421 IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy()));
422 NumInstrumentedVtableReads++;
425 Value *OnAccessFunc = IsWrite ? TsanWrite[Idx] : TsanRead[Idx];
426 IRB.CreateCall(OnAccessFunc, IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy()));
427 if (IsWrite) NumInstrumentedWrites++;
428 else NumInstrumentedReads++;
432 static ConstantInt *createOrdering(IRBuilder<> *IRB, AtomicOrdering ord) {
435 case NotAtomic: assert(false);
436 case Unordered: // Fall-through.
437 case Monotonic: v = 0; break;
438 // case Consume: v = 1; break; // Not specified yet.
439 case Acquire: v = 2; break;
440 case Release: v = 3; break;
441 case AcquireRelease: v = 4; break;
442 case SequentiallyConsistent: v = 5; break;
444 return IRB->getInt32(v);
447 static ConstantInt *createFailOrdering(IRBuilder<> *IRB, AtomicOrdering ord) {
450 case NotAtomic: assert(false);
451 case Unordered: // Fall-through.
452 case Monotonic: v = 0; break;
453 // case Consume: v = 1; break; // Not specified yet.
454 case Acquire: v = 2; break;
455 case Release: v = 0; break;
456 case AcquireRelease: v = 2; break;
457 case SequentiallyConsistent: v = 5; break;
459 return IRB->getInt32(v);
462 // If a memset intrinsic gets inlined by the code gen, we will miss races on it.
463 // So, we either need to ensure the intrinsic is not inlined, or instrument it.
464 // We do not instrument memset/memmove/memcpy intrinsics (too complicated),
465 // instead we simply replace them with regular function calls, which are then
466 // intercepted by the run-time.
467 // Since tsan is running after everyone else, the calls should not be
468 // replaced back with intrinsics. If that becomes wrong at some point,
469 // we will need to call e.g. __tsan_memset to avoid the intrinsics.
470 bool ThreadSanitizer::instrumentMemIntrinsic(Instruction *I) {
472 if (MemSetInst *M = dyn_cast<MemSetInst>(I)) {
473 IRB.CreateCall3(MemsetFn,
474 IRB.CreatePointerCast(M->getArgOperand(0), IRB.getInt8PtrTy()),
475 IRB.CreateIntCast(M->getArgOperand(1), IRB.getInt32Ty(), false),
476 IRB.CreateIntCast(M->getArgOperand(2), IntptrTy, false));
477 I->eraseFromParent();
478 } else if (MemTransferInst *M = dyn_cast<MemTransferInst>(I)) {
479 IRB.CreateCall3(isa<MemCpyInst>(M) ? MemcpyFn : MemmoveFn,
480 IRB.CreatePointerCast(M->getArgOperand(0), IRB.getInt8PtrTy()),
481 IRB.CreatePointerCast(M->getArgOperand(1), IRB.getInt8PtrTy()),
482 IRB.CreateIntCast(M->getArgOperand(2), IntptrTy, false));
483 I->eraseFromParent();
488 // Both llvm and ThreadSanitizer atomic operations are based on C++11/C1x
489 // standards. For background see C++11 standard. A slightly older, publically
490 // available draft of the standard (not entirely up-to-date, but close enough
491 // for casual browsing) is available here:
492 // http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3242.pdf
493 // The following page contains more background information:
494 // http://www.hpl.hp.com/personal/Hans_Boehm/c++mm/
496 bool ThreadSanitizer::instrumentAtomic(Instruction *I) {
498 if (LoadInst *LI = dyn_cast<LoadInst>(I)) {
499 Value *Addr = LI->getPointerOperand();
500 int Idx = getMemoryAccessFuncIndex(Addr);
503 const size_t ByteSize = 1 << Idx;
504 const size_t BitSize = ByteSize * 8;
505 Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
506 Type *PtrTy = Ty->getPointerTo();
507 Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
508 createOrdering(&IRB, LI->getOrdering())};
509 CallInst *C = CallInst::Create(TsanAtomicLoad[Idx],
510 ArrayRef<Value*>(Args));
511 ReplaceInstWithInst(I, C);
513 } else if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
514 Value *Addr = SI->getPointerOperand();
515 int Idx = getMemoryAccessFuncIndex(Addr);
518 const size_t ByteSize = 1 << Idx;
519 const size_t BitSize = ByteSize * 8;
520 Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
521 Type *PtrTy = Ty->getPointerTo();
522 Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
523 IRB.CreateIntCast(SI->getValueOperand(), Ty, false),
524 createOrdering(&IRB, SI->getOrdering())};
525 CallInst *C = CallInst::Create(TsanAtomicStore[Idx],
526 ArrayRef<Value*>(Args));
527 ReplaceInstWithInst(I, C);
528 } else if (AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(I)) {
529 Value *Addr = RMWI->getPointerOperand();
530 int Idx = getMemoryAccessFuncIndex(Addr);
533 Function *F = TsanAtomicRMW[RMWI->getOperation()][Idx];
536 const size_t ByteSize = 1 << Idx;
537 const size_t BitSize = ByteSize * 8;
538 Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
539 Type *PtrTy = Ty->getPointerTo();
540 Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
541 IRB.CreateIntCast(RMWI->getValOperand(), Ty, false),
542 createOrdering(&IRB, RMWI->getOrdering())};
543 CallInst *C = CallInst::Create(F, ArrayRef<Value*>(Args));
544 ReplaceInstWithInst(I, C);
545 } else if (AtomicCmpXchgInst *CASI = dyn_cast<AtomicCmpXchgInst>(I)) {
546 Value *Addr = CASI->getPointerOperand();
547 int Idx = getMemoryAccessFuncIndex(Addr);
550 const size_t ByteSize = 1 << Idx;
551 const size_t BitSize = ByteSize * 8;
552 Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
553 Type *PtrTy = Ty->getPointerTo();
554 Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
555 IRB.CreateIntCast(CASI->getCompareOperand(), Ty, false),
556 IRB.CreateIntCast(CASI->getNewValOperand(), Ty, false),
557 createOrdering(&IRB, CASI->getOrdering()),
558 createFailOrdering(&IRB, CASI->getOrdering())};
559 CallInst *C = CallInst::Create(TsanAtomicCAS[Idx], ArrayRef<Value*>(Args));
560 ReplaceInstWithInst(I, C);
561 } else if (FenceInst *FI = dyn_cast<FenceInst>(I)) {
562 Value *Args[] = {createOrdering(&IRB, FI->getOrdering())};
563 Function *F = FI->getSynchScope() == SingleThread ?
564 TsanAtomicSignalFence : TsanAtomicThreadFence;
565 CallInst *C = CallInst::Create(F, ArrayRef<Value*>(Args));
566 ReplaceInstWithInst(I, C);
571 int ThreadSanitizer::getMemoryAccessFuncIndex(Value *Addr) {
572 Type *OrigPtrTy = Addr->getType();
573 Type *OrigTy = cast<PointerType>(OrigPtrTy)->getElementType();
574 assert(OrigTy->isSized());
575 uint32_t TypeSize = TD->getTypeStoreSizeInBits(OrigTy);
576 if (TypeSize != 8 && TypeSize != 16 &&
577 TypeSize != 32 && TypeSize != 64 && TypeSize != 128) {
578 NumAccessesWithBadSize++;
579 // Ignore all unusual sizes.
582 size_t Idx = CountTrailingZeros_32(TypeSize / 8);
583 assert(Idx < kNumberOfAccessSizes);