+
+static ConstantInt *createOrdering(IRBuilder<> *IRB, AtomicOrdering ord) {
+ uint32_t v = 0;
+ switch (ord) {
+ case NotAtomic: assert(false);
+ case Unordered: // Fall-through.
+ case Monotonic: v = 0; break;
+ // case Consume: v = 1; break; // Not specified yet.
+ case Acquire: v = 2; break;
+ case Release: v = 3; break;
+ case AcquireRelease: v = 4; break;
+ case SequentiallyConsistent: v = 5; break;
+ }
+ return IRB->getInt32(v);
+}
+
+static ConstantInt *createFailOrdering(IRBuilder<> *IRB, AtomicOrdering ord) {
+ uint32_t v = 0;
+ switch (ord) {
+ case NotAtomic: assert(false);
+ case Unordered: // Fall-through.
+ case Monotonic: v = 0; break;
+ // case Consume: v = 1; break; // Not specified yet.
+ case Acquire: v = 2; break;
+ case Release: v = 0; break;
+ case AcquireRelease: v = 2; break;
+ case SequentiallyConsistent: v = 5; break;
+ }
+ return IRB->getInt32(v);
+}
+
+// Both llvm and ThreadSanitizer atomic operations are based on C++11/C1x
+// standards. For background see C++11 standard. A slightly older, publically
+// available draft of the standard (not entirely up-to-date, but close enough
+// for casual browsing) is available here:
+// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3242.pdf
+// The following page contains more background information:
+// http://www.hpl.hp.com/personal/Hans_Boehm/c++mm/
+
+bool ThreadSanitizer::instrumentAtomic(Instruction *I) {
+ IRBuilder<> IRB(I);
+ if (LoadInst *LI = dyn_cast<LoadInst>(I)) {
+ Value *Addr = LI->getPointerOperand();
+ int Idx = getMemoryAccessFuncIndex(Addr);
+ if (Idx < 0)
+ return false;
+ const size_t ByteSize = 1 << Idx;
+ const size_t BitSize = ByteSize * 8;
+ Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
+ Type *PtrTy = Ty->getPointerTo();
+ Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
+ createOrdering(&IRB, LI->getOrdering())};
+ CallInst *C = CallInst::Create(TsanAtomicLoad[Idx],
+ ArrayRef<Value*>(Args));
+ ReplaceInstWithInst(I, C);
+
+ } else if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
+ Value *Addr = SI->getPointerOperand();
+ int Idx = getMemoryAccessFuncIndex(Addr);
+ if (Idx < 0)
+ return false;
+ const size_t ByteSize = 1 << Idx;
+ const size_t BitSize = ByteSize * 8;
+ Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
+ Type *PtrTy = Ty->getPointerTo();
+ Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
+ IRB.CreateIntCast(SI->getValueOperand(), Ty, false),
+ createOrdering(&IRB, SI->getOrdering())};
+ CallInst *C = CallInst::Create(TsanAtomicStore[Idx],
+ ArrayRef<Value*>(Args));
+ ReplaceInstWithInst(I, C);
+ } else if (AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(I)) {
+ Value *Addr = RMWI->getPointerOperand();
+ int Idx = getMemoryAccessFuncIndex(Addr);
+ if (Idx < 0)
+ return false;
+ Function *F = TsanAtomicRMW[RMWI->getOperation()][Idx];
+ if (F == NULL)
+ return false;
+ const size_t ByteSize = 1 << Idx;
+ const size_t BitSize = ByteSize * 8;
+ Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
+ Type *PtrTy = Ty->getPointerTo();
+ Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
+ IRB.CreateIntCast(RMWI->getValOperand(), Ty, false),
+ createOrdering(&IRB, RMWI->getOrdering())};
+ CallInst *C = CallInst::Create(F, ArrayRef<Value*>(Args));
+ ReplaceInstWithInst(I, C);
+ } else if (AtomicCmpXchgInst *CASI = dyn_cast<AtomicCmpXchgInst>(I)) {
+ Value *Addr = CASI->getPointerOperand();
+ int Idx = getMemoryAccessFuncIndex(Addr);
+ if (Idx < 0)
+ return false;
+ const size_t ByteSize = 1 << Idx;
+ const size_t BitSize = ByteSize * 8;
+ Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
+ Type *PtrTy = Ty->getPointerTo();
+ Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
+ IRB.CreateIntCast(CASI->getCompareOperand(), Ty, false),
+ IRB.CreateIntCast(CASI->getNewValOperand(), Ty, false),
+ createOrdering(&IRB, CASI->getOrdering()),
+ createFailOrdering(&IRB, CASI->getOrdering())};
+ CallInst *C = CallInst::Create(TsanAtomicCAS[Idx], ArrayRef<Value*>(Args));
+ ReplaceInstWithInst(I, C);
+ } else if (FenceInst *FI = dyn_cast<FenceInst>(I)) {
+ Value *Args[] = {createOrdering(&IRB, FI->getOrdering())};
+ Function *F = FI->getSynchScope() == SingleThread ?
+ TsanAtomicSignalFence : TsanAtomicThreadFence;
+ CallInst *C = CallInst::Create(F, ArrayRef<Value*>(Args));
+ ReplaceInstWithInst(I, C);
+ }
+ return true;
+}
+
+int ThreadSanitizer::getMemoryAccessFuncIndex(Value *Addr) {
+ Type *OrigPtrTy = Addr->getType();
+ Type *OrigTy = cast<PointerType>(OrigPtrTy)->getElementType();
+ assert(OrigTy->isSized());
+ uint32_t TypeSize = TD->getTypeStoreSizeInBits(OrigTy);
+ if (TypeSize != 8 && TypeSize != 16 &&
+ TypeSize != 32 && TypeSize != 64 && TypeSize != 128) {
+ NumAccessesWithBadSize++;
+ // Ignore all unusual sizes.
+ return -1;
+ }
+ size_t Idx = CountTrailingZeros_32(TypeSize / 8);
+ assert(Idx < kNumberOfAccessSizes);
+ return Idx;
+}