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 #include "llvm/Transforms/Instrumentation.h"
23 #include "llvm/ADT/SmallSet.h"
24 #include "llvm/ADT/SmallString.h"
25 #include "llvm/ADT/SmallVector.h"
26 #include "llvm/ADT/Statistic.h"
27 #include "llvm/ADT/StringExtras.h"
28 #include "llvm/IR/DataLayout.h"
29 #include "llvm/IR/Function.h"
30 #include "llvm/IR/IRBuilder.h"
31 #include "llvm/IR/IntrinsicInst.h"
32 #include "llvm/IR/Intrinsics.h"
33 #include "llvm/IR/LLVMContext.h"
34 #include "llvm/IR/Metadata.h"
35 #include "llvm/IR/Module.h"
36 #include "llvm/IR/Type.h"
37 #include "llvm/Support/CommandLine.h"
38 #include "llvm/Support/Debug.h"
39 #include "llvm/Support/MathExtras.h"
40 #include "llvm/Support/raw_ostream.h"
41 #include "llvm/Transforms/Utils/BasicBlockUtils.h"
42 #include "llvm/Transforms/Utils/ModuleUtils.h"
46 #define DEBUG_TYPE "tsan"
48 static cl::opt<bool> ClInstrumentMemoryAccesses(
49 "tsan-instrument-memory-accesses", cl::init(true),
50 cl::desc("Instrument memory accesses"), cl::Hidden);
51 static cl::opt<bool> ClInstrumentFuncEntryExit(
52 "tsan-instrument-func-entry-exit", cl::init(true),
53 cl::desc("Instrument function entry and exit"), cl::Hidden);
54 static cl::opt<bool> ClInstrumentAtomics(
55 "tsan-instrument-atomics", cl::init(true),
56 cl::desc("Instrument atomics"), cl::Hidden);
57 static cl::opt<bool> ClInstrumentMemIntrinsics(
58 "tsan-instrument-memintrinsics", cl::init(true),
59 cl::desc("Instrument memintrinsics (memset/memcpy/memmove)"), cl::Hidden);
61 STATISTIC(NumInstrumentedReads, "Number of instrumented reads");
62 STATISTIC(NumInstrumentedWrites, "Number of instrumented writes");
63 STATISTIC(NumOmittedReadsBeforeWrite,
64 "Number of reads ignored due to following writes");
65 STATISTIC(NumAccessesWithBadSize, "Number of accesses with bad size");
66 STATISTIC(NumInstrumentedVtableWrites, "Number of vtable ptr writes");
67 STATISTIC(NumInstrumentedVtableReads, "Number of vtable ptr reads");
68 STATISTIC(NumOmittedReadsFromConstantGlobals,
69 "Number of reads from constant globals");
70 STATISTIC(NumOmittedReadsFromVtable, "Number of vtable reads");
74 /// ThreadSanitizer: instrument the code in module to find races.
75 struct ThreadSanitizer : public FunctionPass {
76 ThreadSanitizer() : FunctionPass(ID), DL(nullptr) {}
77 const char *getPassName() const override;
78 bool runOnFunction(Function &F) override;
79 bool doInitialization(Module &M) override;
80 static char ID; // Pass identification, replacement for typeid.
83 void initializeCallbacks(Module &M);
84 bool instrumentLoadOrStore(Instruction *I);
85 bool instrumentAtomic(Instruction *I);
86 bool instrumentMemIntrinsic(Instruction *I);
87 void chooseInstructionsToInstrument(SmallVectorImpl<Instruction*> &Local,
88 SmallVectorImpl<Instruction*> &All);
89 bool addrPointsToConstantData(Value *Addr);
90 int getMemoryAccessFuncIndex(Value *Addr);
95 // Callbacks to run-time library are computed in doInitialization.
96 Function *TsanFuncEntry;
97 Function *TsanFuncExit;
98 // Accesses sizes are powers of two: 1, 2, 4, 8, 16.
99 static const size_t kNumberOfAccessSizes = 5;
100 Function *TsanRead[kNumberOfAccessSizes];
101 Function *TsanWrite[kNumberOfAccessSizes];
102 Function *TsanUnalignedRead[kNumberOfAccessSizes];
103 Function *TsanUnalignedWrite[kNumberOfAccessSizes];
104 Function *TsanAtomicLoad[kNumberOfAccessSizes];
105 Function *TsanAtomicStore[kNumberOfAccessSizes];
106 Function *TsanAtomicRMW[AtomicRMWInst::LAST_BINOP + 1][kNumberOfAccessSizes];
107 Function *TsanAtomicCAS[kNumberOfAccessSizes];
108 Function *TsanAtomicThreadFence;
109 Function *TsanAtomicSignalFence;
110 Function *TsanVptrUpdate;
111 Function *TsanVptrLoad;
112 Function *MemmoveFn, *MemcpyFn, *MemsetFn;
116 char ThreadSanitizer::ID = 0;
117 INITIALIZE_PASS(ThreadSanitizer, "tsan",
118 "ThreadSanitizer: detects data races.",
121 const char *ThreadSanitizer::getPassName() const {
122 return "ThreadSanitizer";
125 FunctionPass *llvm::createThreadSanitizerPass() {
126 return new ThreadSanitizer();
129 static Function *checkInterfaceFunction(Constant *FuncOrBitcast) {
130 if (Function *F = dyn_cast<Function>(FuncOrBitcast))
132 FuncOrBitcast->dump();
133 report_fatal_error("ThreadSanitizer interface function redefined");
136 void ThreadSanitizer::initializeCallbacks(Module &M) {
137 IRBuilder<> IRB(M.getContext());
138 // Initialize the callbacks.
139 TsanFuncEntry = checkInterfaceFunction(M.getOrInsertFunction(
140 "__tsan_func_entry", IRB.getVoidTy(), IRB.getInt8PtrTy(), nullptr));
141 TsanFuncExit = checkInterfaceFunction(M.getOrInsertFunction(
142 "__tsan_func_exit", IRB.getVoidTy(), nullptr));
143 OrdTy = IRB.getInt32Ty();
144 for (size_t i = 0; i < kNumberOfAccessSizes; ++i) {
145 const size_t ByteSize = 1 << i;
146 const size_t BitSize = ByteSize * 8;
147 SmallString<32> ReadName("__tsan_read" + itostr(ByteSize));
148 TsanRead[i] = checkInterfaceFunction(M.getOrInsertFunction(
149 ReadName, IRB.getVoidTy(), IRB.getInt8PtrTy(), nullptr));
151 SmallString<32> WriteName("__tsan_write" + itostr(ByteSize));
152 TsanWrite[i] = checkInterfaceFunction(M.getOrInsertFunction(
153 WriteName, IRB.getVoidTy(), IRB.getInt8PtrTy(), nullptr));
155 SmallString<64> UnalignedReadName("__tsan_unaligned_read" +
157 TsanUnalignedRead[i] = checkInterfaceFunction(M.getOrInsertFunction(
158 UnalignedReadName, IRB.getVoidTy(), IRB.getInt8PtrTy(), nullptr));
160 SmallString<64> UnalignedWriteName("__tsan_unaligned_write" +
162 TsanUnalignedWrite[i] = checkInterfaceFunction(M.getOrInsertFunction(
163 UnalignedWriteName, IRB.getVoidTy(), IRB.getInt8PtrTy(), nullptr));
165 Type *Ty = Type::getIntNTy(M.getContext(), BitSize);
166 Type *PtrTy = Ty->getPointerTo();
167 SmallString<32> AtomicLoadName("__tsan_atomic" + itostr(BitSize) +
169 TsanAtomicLoad[i] = checkInterfaceFunction(M.getOrInsertFunction(
170 AtomicLoadName, Ty, PtrTy, OrdTy, nullptr));
172 SmallString<32> AtomicStoreName("__tsan_atomic" + itostr(BitSize) +
174 TsanAtomicStore[i] = checkInterfaceFunction(M.getOrInsertFunction(
175 AtomicStoreName, IRB.getVoidTy(), PtrTy, Ty, OrdTy,
178 for (int op = AtomicRMWInst::FIRST_BINOP;
179 op <= AtomicRMWInst::LAST_BINOP; ++op) {
180 TsanAtomicRMW[op][i] = nullptr;
181 const char *NamePart = nullptr;
182 if (op == AtomicRMWInst::Xchg)
183 NamePart = "_exchange";
184 else if (op == AtomicRMWInst::Add)
185 NamePart = "_fetch_add";
186 else if (op == AtomicRMWInst::Sub)
187 NamePart = "_fetch_sub";
188 else if (op == AtomicRMWInst::And)
189 NamePart = "_fetch_and";
190 else if (op == AtomicRMWInst::Or)
191 NamePart = "_fetch_or";
192 else if (op == AtomicRMWInst::Xor)
193 NamePart = "_fetch_xor";
194 else if (op == AtomicRMWInst::Nand)
195 NamePart = "_fetch_nand";
198 SmallString<32> RMWName("__tsan_atomic" + itostr(BitSize) + NamePart);
199 TsanAtomicRMW[op][i] = checkInterfaceFunction(M.getOrInsertFunction(
200 RMWName, Ty, PtrTy, Ty, OrdTy, nullptr));
203 SmallString<32> AtomicCASName("__tsan_atomic" + itostr(BitSize) +
204 "_compare_exchange_val");
205 TsanAtomicCAS[i] = checkInterfaceFunction(M.getOrInsertFunction(
206 AtomicCASName, Ty, PtrTy, Ty, Ty, OrdTy, OrdTy, nullptr));
208 TsanVptrUpdate = checkInterfaceFunction(M.getOrInsertFunction(
209 "__tsan_vptr_update", IRB.getVoidTy(), IRB.getInt8PtrTy(),
210 IRB.getInt8PtrTy(), nullptr));
211 TsanVptrLoad = checkInterfaceFunction(M.getOrInsertFunction(
212 "__tsan_vptr_read", IRB.getVoidTy(), IRB.getInt8PtrTy(), nullptr));
213 TsanAtomicThreadFence = checkInterfaceFunction(M.getOrInsertFunction(
214 "__tsan_atomic_thread_fence", IRB.getVoidTy(), OrdTy, nullptr));
215 TsanAtomicSignalFence = checkInterfaceFunction(M.getOrInsertFunction(
216 "__tsan_atomic_signal_fence", IRB.getVoidTy(), OrdTy, nullptr));
218 MemmoveFn = checkInterfaceFunction(M.getOrInsertFunction(
219 "memmove", IRB.getInt8PtrTy(), IRB.getInt8PtrTy(),
220 IRB.getInt8PtrTy(), IntptrTy, nullptr));
221 MemcpyFn = checkInterfaceFunction(M.getOrInsertFunction(
222 "memcpy", IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), IRB.getInt8PtrTy(),
224 MemsetFn = checkInterfaceFunction(M.getOrInsertFunction(
225 "memset", IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), IRB.getInt32Ty(),
229 bool ThreadSanitizer::doInitialization(Module &M) {
230 DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
232 report_fatal_error("data layout missing");
233 DL = &DLP->getDataLayout();
235 // Always insert a call to __tsan_init into the module's CTORs.
236 IRBuilder<> IRB(M.getContext());
237 IntptrTy = IRB.getIntPtrTy(DL);
238 Value *TsanInit = M.getOrInsertFunction("__tsan_init",
239 IRB.getVoidTy(), nullptr);
240 appendToGlobalCtors(M, cast<Function>(TsanInit), 0);
245 static bool isVtableAccess(Instruction *I) {
246 if (MDNode *Tag = I->getMetadata(LLVMContext::MD_tbaa))
247 return Tag->isTBAAVtableAccess();
251 bool ThreadSanitizer::addrPointsToConstantData(Value *Addr) {
252 // If this is a GEP, just analyze its pointer operand.
253 if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Addr))
254 Addr = GEP->getPointerOperand();
256 if (GlobalVariable *GV = dyn_cast<GlobalVariable>(Addr)) {
257 if (GV->isConstant()) {
258 // Reads from constant globals can not race with any writes.
259 NumOmittedReadsFromConstantGlobals++;
262 } else if (LoadInst *L = dyn_cast<LoadInst>(Addr)) {
263 if (isVtableAccess(L)) {
264 // Reads from a vtable pointer can not race with any writes.
265 NumOmittedReadsFromVtable++;
272 // Instrumenting some of the accesses may be proven redundant.
273 // Currently handled:
274 // - read-before-write (within same BB, no calls between)
276 // We do not handle some of the patterns that should not survive
277 // after the classic compiler optimizations.
278 // E.g. two reads from the same temp should be eliminated by CSE,
279 // two writes should be eliminated by DSE, etc.
281 // 'Local' is a vector of insns within the same BB (no calls between).
282 // 'All' is a vector of insns that will be instrumented.
283 void ThreadSanitizer::chooseInstructionsToInstrument(
284 SmallVectorImpl<Instruction*> &Local,
285 SmallVectorImpl<Instruction*> &All) {
286 SmallSet<Value*, 8> WriteTargets;
287 // Iterate from the end.
288 for (SmallVectorImpl<Instruction*>::reverse_iterator It = Local.rbegin(),
289 E = Local.rend(); It != E; ++It) {
290 Instruction *I = *It;
291 if (StoreInst *Store = dyn_cast<StoreInst>(I)) {
292 WriteTargets.insert(Store->getPointerOperand());
294 LoadInst *Load = cast<LoadInst>(I);
295 Value *Addr = Load->getPointerOperand();
296 if (WriteTargets.count(Addr)) {
297 // We will write to this temp, so no reason to analyze the read.
298 NumOmittedReadsBeforeWrite++;
301 if (addrPointsToConstantData(Addr)) {
302 // Addr points to some constant data -- it can not race with any writes.
311 static bool isAtomic(Instruction *I) {
312 if (LoadInst *LI = dyn_cast<LoadInst>(I))
313 return LI->isAtomic() && LI->getSynchScope() == CrossThread;
314 if (StoreInst *SI = dyn_cast<StoreInst>(I))
315 return SI->isAtomic() && SI->getSynchScope() == CrossThread;
316 if (isa<AtomicRMWInst>(I))
318 if (isa<AtomicCmpXchgInst>(I))
320 if (isa<FenceInst>(I))
325 bool ThreadSanitizer::runOnFunction(Function &F) {
326 if (!DL) return false;
327 initializeCallbacks(*F.getParent());
328 SmallVector<Instruction*, 8> RetVec;
329 SmallVector<Instruction*, 8> AllLoadsAndStores;
330 SmallVector<Instruction*, 8> LocalLoadsAndStores;
331 SmallVector<Instruction*, 8> AtomicAccesses;
332 SmallVector<Instruction*, 8> MemIntrinCalls;
334 bool HasCalls = false;
335 bool SanitizeFunction = F.hasFnAttribute(Attribute::SanitizeThread);
337 // Traverse all instructions, collect loads/stores/returns, check for calls.
339 for (auto &Inst : BB) {
341 AtomicAccesses.push_back(&Inst);
342 else if (isa<LoadInst>(Inst) || isa<StoreInst>(Inst))
343 LocalLoadsAndStores.push_back(&Inst);
344 else if (isa<ReturnInst>(Inst))
345 RetVec.push_back(&Inst);
346 else if (isa<CallInst>(Inst) || isa<InvokeInst>(Inst)) {
347 if (isa<MemIntrinsic>(Inst))
348 MemIntrinCalls.push_back(&Inst);
350 chooseInstructionsToInstrument(LocalLoadsAndStores, AllLoadsAndStores);
353 chooseInstructionsToInstrument(LocalLoadsAndStores, AllLoadsAndStores);
356 // We have collected all loads and stores.
357 // FIXME: many of these accesses do not need to be checked for races
358 // (e.g. variables that do not escape, etc).
360 // Instrument memory accesses only if we want to report bugs in the function.
361 if (ClInstrumentMemoryAccesses && SanitizeFunction)
362 for (auto Inst : AllLoadsAndStores) {
363 Res |= instrumentLoadOrStore(Inst);
366 // Instrument atomic memory accesses in any case (they can be used to
367 // implement synchronization).
368 if (ClInstrumentAtomics)
369 for (auto Inst : AtomicAccesses) {
370 Res |= instrumentAtomic(Inst);
373 if (ClInstrumentMemIntrinsics && SanitizeFunction)
374 for (auto Inst : MemIntrinCalls) {
375 Res |= instrumentMemIntrinsic(Inst);
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),
384 IRB.CreateCall(TsanFuncEntry, ReturnAddress);
385 for (auto RetInst : RetVec) {
386 IRBuilder<> IRBRet(RetInst);
387 IRBRet.CreateCall(TsanFuncExit);
394 bool ThreadSanitizer::instrumentLoadOrStore(Instruction *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);
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++;
421 if (!IsWrite && isVtableAccess(I)) {
422 IRB.CreateCall(TsanVptrLoad,
423 IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy()));
424 NumInstrumentedVtableReads++;
427 const unsigned Alignment = IsWrite
428 ? cast<StoreInst>(I)->getAlignment()
429 : cast<LoadInst>(I)->getAlignment();
430 Type *OrigTy = cast<PointerType>(Addr->getType())->getElementType();
431 const uint32_t TypeSize = DL->getTypeStoreSizeInBits(OrigTy);
432 Value *OnAccessFunc = nullptr;
433 if (Alignment == 0 || Alignment >= 8 || (Alignment % (TypeSize / 8)) == 0)
434 OnAccessFunc = IsWrite ? TsanWrite[Idx] : TsanRead[Idx];
436 OnAccessFunc = IsWrite ? TsanUnalignedWrite[Idx] : TsanUnalignedRead[Idx];
437 IRB.CreateCall(OnAccessFunc, IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy()));
438 if (IsWrite) NumInstrumentedWrites++;
439 else NumInstrumentedReads++;
443 static ConstantInt *createOrdering(IRBuilder<> *IRB, AtomicOrdering ord) {
446 case NotAtomic: llvm_unreachable("unexpected atomic ordering!");
447 case Unordered: // Fall-through.
448 case Monotonic: v = 0; break;
449 // case Consume: v = 1; break; // Not specified yet.
450 case Acquire: v = 2; break;
451 case Release: v = 3; break;
452 case AcquireRelease: v = 4; break;
453 case SequentiallyConsistent: v = 5; break;
455 return IRB->getInt32(v);
458 // If a memset intrinsic gets inlined by the code gen, we will miss races on it.
459 // So, we either need to ensure the intrinsic is not inlined, or instrument it.
460 // We do not instrument memset/memmove/memcpy intrinsics (too complicated),
461 // instead we simply replace them with regular function calls, which are then
462 // intercepted by the run-time.
463 // Since tsan is running after everyone else, the calls should not be
464 // replaced back with intrinsics. If that becomes wrong at some point,
465 // we will need to call e.g. __tsan_memset to avoid the intrinsics.
466 bool ThreadSanitizer::instrumentMemIntrinsic(Instruction *I) {
468 if (MemSetInst *M = dyn_cast<MemSetInst>(I)) {
469 IRB.CreateCall3(MemsetFn,
470 IRB.CreatePointerCast(M->getArgOperand(0), IRB.getInt8PtrTy()),
471 IRB.CreateIntCast(M->getArgOperand(1), IRB.getInt32Ty(), false),
472 IRB.CreateIntCast(M->getArgOperand(2), IntptrTy, false));
473 I->eraseFromParent();
474 } else if (MemTransferInst *M = dyn_cast<MemTransferInst>(I)) {
475 IRB.CreateCall3(isa<MemCpyInst>(M) ? MemcpyFn : MemmoveFn,
476 IRB.CreatePointerCast(M->getArgOperand(0), IRB.getInt8PtrTy()),
477 IRB.CreatePointerCast(M->getArgOperand(1), IRB.getInt8PtrTy()),
478 IRB.CreateIntCast(M->getArgOperand(2), IntptrTy, false));
479 I->eraseFromParent();
484 // Both llvm and ThreadSanitizer atomic operations are based on C++11/C1x
485 // standards. For background see C++11 standard. A slightly older, publicly
486 // available draft of the standard (not entirely up-to-date, but close enough
487 // for casual browsing) is available here:
488 // http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3242.pdf
489 // The following page contains more background information:
490 // http://www.hpl.hp.com/personal/Hans_Boehm/c++mm/
492 bool ThreadSanitizer::instrumentAtomic(Instruction *I) {
494 if (LoadInst *LI = dyn_cast<LoadInst>(I)) {
495 Value *Addr = LI->getPointerOperand();
496 int Idx = getMemoryAccessFuncIndex(Addr);
499 const size_t ByteSize = 1 << Idx;
500 const size_t BitSize = ByteSize * 8;
501 Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
502 Type *PtrTy = Ty->getPointerTo();
503 Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
504 createOrdering(&IRB, LI->getOrdering())};
505 CallInst *C = CallInst::Create(TsanAtomicLoad[Idx], Args);
506 ReplaceInstWithInst(I, C);
508 } else if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
509 Value *Addr = SI->getPointerOperand();
510 int Idx = getMemoryAccessFuncIndex(Addr);
513 const size_t ByteSize = 1 << Idx;
514 const size_t BitSize = ByteSize * 8;
515 Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
516 Type *PtrTy = Ty->getPointerTo();
517 Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
518 IRB.CreateIntCast(SI->getValueOperand(), Ty, false),
519 createOrdering(&IRB, SI->getOrdering())};
520 CallInst *C = CallInst::Create(TsanAtomicStore[Idx], Args);
521 ReplaceInstWithInst(I, C);
522 } else if (AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(I)) {
523 Value *Addr = RMWI->getPointerOperand();
524 int Idx = getMemoryAccessFuncIndex(Addr);
527 Function *F = TsanAtomicRMW[RMWI->getOperation()][Idx];
530 const size_t ByteSize = 1 << Idx;
531 const size_t BitSize = ByteSize * 8;
532 Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
533 Type *PtrTy = Ty->getPointerTo();
534 Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
535 IRB.CreateIntCast(RMWI->getValOperand(), Ty, false),
536 createOrdering(&IRB, RMWI->getOrdering())};
537 CallInst *C = CallInst::Create(F, Args);
538 ReplaceInstWithInst(I, C);
539 } else if (AtomicCmpXchgInst *CASI = dyn_cast<AtomicCmpXchgInst>(I)) {
540 Value *Addr = CASI->getPointerOperand();
541 int Idx = getMemoryAccessFuncIndex(Addr);
544 const size_t ByteSize = 1 << Idx;
545 const size_t BitSize = ByteSize * 8;
546 Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
547 Type *PtrTy = Ty->getPointerTo();
548 Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
549 IRB.CreateIntCast(CASI->getCompareOperand(), Ty, false),
550 IRB.CreateIntCast(CASI->getNewValOperand(), Ty, false),
551 createOrdering(&IRB, CASI->getSuccessOrdering()),
552 createOrdering(&IRB, CASI->getFailureOrdering())};
553 CallInst *C = IRB.CreateCall(TsanAtomicCAS[Idx], Args);
554 Value *Success = IRB.CreateICmpEQ(C, CASI->getCompareOperand());
556 Value *Res = IRB.CreateInsertValue(UndefValue::get(CASI->getType()), C, 0);
557 Res = IRB.CreateInsertValue(Res, Success, 1);
559 I->replaceAllUsesWith(Res);
560 I->eraseFromParent();
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, 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 = DL->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(TypeSize / 8);
583 assert(Idx < kNumberOfAccessSizes);