[dfsan] Rename ShadowTy/ZeroShadow with prefix Primitive

[stephan.yichao.zhao]

Summary

This is a child diff of D92261.

After supporting field/index-level shadow, the existing shadow with type
i16 works for only primitive types.

[morehouse]

What is a "primary" type? Maybe we can pick a more descriptive name, or at least write a comment somewhere in the code explaining the difference between primary and not primary types/shadows.

[stephan.yichao.zhao]

Sorry. This was a typo.

renamed Primary to Primitive

In D92261, values with primitive types like(i1, double, void*) have i16 shadow values,
and aggregate types have shadow values with i16 shadow values at leaves with primitive
types. Vectors should have non-primitive shadow values too, but at an incrementally
implementation, D92261 still assignes i16 to vectors.

The comments around PrimitiveShadowTy will be updated in the following diffs.

[stephan.yichao.zhao]

update

[morehouse]

llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp

357–362

365

I think this comment is unnecessary since the previous comment explains enough.

[stephan.yichao.zhao]

update

llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp

enum WrapperKind {
     /// extra pointer argument to return the shadow.  This allows the wrapped
     /// form of the function type to be expressed in C.
     WK_Custom
   };
 
   Module *Mod;
   LLVMContext *Ctx;
   Type *Int8Ptr;
-  IntegerType *ShadowTy;
-  PointerType *ShadowPtrTy;
+  /// The shadow type for all primitive types. Until we support field/index
+  /// level shadow values, aggregate and vector types also use this shadow
+  /// type.
+  IntegerType *PrimitiveShadowTy;
+  PointerType *PrimitiveShadowPtrTy;
   IntegerType *IntptrTy;
-  ConstantInt *ZeroShadow;
+  ConstantInt *ZeroPrimitiveShadow;
   ConstantInt *ShadowPtrMask;
   ConstantInt *ShadowPtrMul;
   Constant *ArgTLS;
   Constant *RetvalTLS;
   Constant *ExternalShadowMask;
   FunctionType *DFSanUnionFnTy;
   FunctionType *DFSanUnionLoadFnTy;
   FunctionType *DFSanUnimplementedFnTy;
   FunctionType *DFSanSetLabelFnTy;
   FunctionType *DFSanNonzeroLabelFnTy;
AllABIListFiles.insert(AllABIListFiles.end(), ClABIListFiles.begin(),
                          ClABIListFiles.end());
   // FIXME: should we propagate vfs::FileSystem to this constructor?
   ABIList.set(
       SpecialCaseList::createOrDie(AllABIListFiles, *vfs::getRealFileSystem()));
 }
 
 FunctionType *DataFlowSanitizer::getArgsFunctionType(FunctionType *T) {
   SmallVector<Type *, 4> ArgTypes(T->param_begin(), T->param_end());
-  ArgTypes.append(T->getNumParams(), ShadowTy);
+  ArgTypes.append(T->getNumParams(), PrimitiveShadowTy);
   if (T->isVarArg())
-    ArgTypes.push_back(ShadowPtrTy);
+    ArgTypes.push_back(PrimitiveShadowPtrTy);
   Type *RetType = T->getReturnType();
   if (!RetType->isVoidTy())
-    RetType = StructType::get(RetType, ShadowTy);
+    RetType = StructType::get(RetType, PrimitiveShadowTy);
   return FunctionType::get(RetType, ArgTypes, T->isVarArg());
 }
 
 FunctionType *DataFlowSanitizer::getTrampolineFunctionType(FunctionType *T) {
   assert(!T->isVarArg());
   SmallVector<Type *, 4> ArgTypes;
   ArgTypes.push_back(T->getPointerTo());
   ArgTypes.append(T->param_begin(), T->param_end());
-  ArgTypes.append(T->getNumParams(), ShadowTy);
+  ArgTypes.append(T->getNumParams(), PrimitiveShadowTy);
   Type *RetType = T->getReturnType();
   if (!RetType->isVoidTy())
-    ArgTypes.push_back(ShadowPtrTy);
+    ArgTypes.push_back(PrimitiveShadowPtrTy);
   return FunctionType::get(T->getReturnType(), ArgTypes, false);
 }
 
 TransformedFunction DataFlowSanitizer::getCustomFunctionType(FunctionType *T) {
   SmallVector<Type *, 4> ArgTypes;
 
   // Some parameters of the custom function being constructed are
   // parameters of T.  Record the mapping from parameters of T to
if (isa<PointerType>(param_type) && (FT = dyn_cast<FunctionType>(
       ArgTypes.push_back(getTrampolineFunctionType(FT)->getPointerTo());
       ArgTypes.push_back(Type::getInt8PtrTy(*Ctx));
     } else {
       ArgumentIndexMapping.push_back(ArgTypes.size());
       ArgTypes.push_back(param_type);
     }
   }
   for (unsigned i = 0, e = T->getNumParams(); i != e; ++i)
-    ArgTypes.push_back(ShadowTy);
+    ArgTypes.push_back(PrimitiveShadowTy);
   if (T->isVarArg())
-    ArgTypes.push_back(ShadowPtrTy);
+    ArgTypes.push_back(PrimitiveShadowPtrTy);
   Type *RetType = T->getReturnType();
   if (!RetType->isVoidTy())
-    ArgTypes.push_back(ShadowPtrTy);
+    ArgTypes.push_back(PrimitiveShadowPtrTy);
   return TransformedFunction(
       T, FunctionType::get(T->getReturnType(), ArgTypes, T->isVarArg()),
       ArgumentIndexMapping);
 }
 
 bool DataFlowSanitizer::init(Module &M) {
   Triple TargetTriple(M.getTargetTriple());
   bool IsX86_64 = TargetTriple.getArch() == Triple::x86_64;
   bool IsMIPS64 = TargetTriple.isMIPS64();
   bool IsAArch64 = TargetTriple.getArch() == Triple::aarch64 ||
                    TargetTriple.getArch() == Triple::aarch64_be;
 
   const DataLayout &DL = M.getDataLayout();
 
   Mod = &M;
   Ctx = &M.getContext();
   Int8Ptr = Type::getInt8PtrTy(*Ctx);
-  ShadowTy = IntegerType::get(*Ctx, ShadowWidthBits);
-  ShadowPtrTy = PointerType::getUnqual(ShadowTy);
+  PrimitiveShadowTy = IntegerType::get(*Ctx, ShadowWidthBits);
+  PrimitiveShadowPtrTy = PointerType::getUnqual(PrimitiveShadowTy);
   IntptrTy = DL.getIntPtrType(*Ctx);
-  ZeroShadow = ConstantInt::getSigned(ShadowTy, 0);
+  ZeroPrimitiveShadow = ConstantInt::getSigned(PrimitiveShadowTy, 0);
   ShadowPtrMul = ConstantInt::getSigned(IntptrTy, ShadowWidthBytes);
   if (IsX86_64)
     ShadowPtrMask = ConstantInt::getSigned(IntptrTy, ~0x700000000000LL);
   else if (IsMIPS64)
     ShadowPtrMask = ConstantInt::getSigned(IntptrTy, ~0xF000000000LL);
   // AArch64 supports multiple VMAs and the shadow mask is set at runtime.
   else if (IsAArch64)
     DFSanRuntimeShadowMask = true;
   else
     report_fatal_error("unsupported triple");
 
-  Type *DFSanUnionArgs[2] = { ShadowTy, ShadowTy };
+  Type *DFSanUnionArgs[2] = {PrimitiveShadowTy, PrimitiveShadowTy};
   DFSanUnionFnTy =
-      FunctionType::get(ShadowTy, DFSanUnionArgs, /*isVarArg=*/ false);
-  Type *DFSanUnionLoadArgs[2] = { ShadowPtrTy, IntptrTy };
-  DFSanUnionLoadFnTy =
-      FunctionType::get(ShadowTy, DFSanUnionLoadArgs, /*isVarArg=*/ false);
+      FunctionType::get(PrimitiveShadowTy, DFSanUnionArgs, /*isVarArg=*/false);
+  Type *DFSanUnionLoadArgs[2] = {PrimitiveShadowPtrTy, IntptrTy};
+  DFSanUnionLoadFnTy = FunctionType::get(PrimitiveShadowTy, DFSanUnionLoadArgs,
+                                         /*isVarArg=*/false);
   DFSanUnimplementedFnTy = FunctionType::get(
       Type::getVoidTy(*Ctx), Type::getInt8PtrTy(*Ctx), /*isVarArg=*/false);
-  Type *DFSanSetLabelArgs[3] = { ShadowTy, Type::getInt8PtrTy(*Ctx), IntptrTy };
+  Type *DFSanSetLabelArgs[3] = {PrimitiveShadowTy, Type::getInt8PtrTy(*Ctx),
+                                IntptrTy};
   DFSanSetLabelFnTy = FunctionType::get(Type::getVoidTy(*Ctx),
                                         DFSanSetLabelArgs, /*isVarArg=*/false);
-  DFSanNonzeroLabelFnTy = FunctionType::get(
-      Type::getVoidTy(*Ctx), None, /*isVarArg=*/false);
+  DFSanNonzeroLabelFnTy =
+      FunctionType::get(Type::getVoidTy(*Ctx), None, /*isVarArg=*/false);
   DFSanVarargWrapperFnTy = FunctionType::get(
       Type::getVoidTy(*Ctx), Type::getInt8PtrTy(*Ctx), /*isVarArg=*/false);
-  DFSanCmpCallbackFnTy = FunctionType::get(Type::getVoidTy(*Ctx), ShadowTy,
-                                           /*isVarArg=*/false);
-  Type *DFSanLoadStoreCallbackArgs[2] = {ShadowTy, Int8Ptr};
+  DFSanCmpCallbackFnTy =
+      FunctionType::get(Type::getVoidTy(*Ctx), PrimitiveShadowTy,
+  Type *DFSanLoadStoreCallbackArgs[2] = {PrimitiveShadowTy, Int8Ptr};
   DFSanLoadStoreCallbackFnTy =
       FunctionType::get(Type::getVoidTy(*Ctx), DFSanLoadStoreCallbackArgs,
                         /*isVarArg=*/false);
-  Type *DFSanMemTransferCallbackArgs[2] = {ShadowPtrTy, IntptrTy};
+  Type *DFSanMemTransferCallbackArgs[2] = {PrimitiveShadowPtrTy, IntptrTy};
   DFSanMemTransferCallbackFnTy =
       FunctionType::get(Type::getVoidTy(*Ctx), DFSanMemTransferCallbackArgs,
                         /*isVarArg=*/false);
 
   ColdCallWeights = MDBuilder(*Ctx).createBranchWeights(1, 1000);
   return true;
 }
 
bool DataFlowSanitizer::runImpl(Module &M) {
   if (ABIList.isIn(M, "skip"))
     return false;
 
   const unsigned InitialGlobalSize = M.global_size();
   const unsigned InitialModuleSize = M.size();
 
   bool Changed = false;
 
-  Type *ArgTLSTy = ArrayType::get(ShadowTy, 64);
+  Type *ArgTLSTy = ArrayType::get(PrimitiveShadowTy, 64);
   ArgTLS = Mod->getOrInsertGlobal("__dfsan_arg_tls", ArgTLSTy);
   if (GlobalVariable *G = dyn_cast<GlobalVariable>(ArgTLS)) {
     Changed |= G->getThreadLocalMode() != GlobalVariable::InitialExecTLSModel;
     G->setThreadLocalMode(GlobalVariable::InitialExecTLSModel);
   }
-  RetvalTLS = Mod->getOrInsertGlobal("__dfsan_retval_tls", ShadowTy);
+  RetvalTLS = Mod->getOrInsertGlobal("__dfsan_retval_tls", PrimitiveShadowTy);
   if (GlobalVariable *G = dyn_cast<GlobalVariable>(RetvalTLS)) {
     Changed |= G->getThreadLocalMode() != GlobalVariable::InitialExecTLSModel;
     G->setThreadLocalMode(GlobalVariable::InitialExecTLSModel);
   }
 
   ExternalShadowMask =
       Mod->getOrInsertGlobal(kDFSanExternShadowPtrMask, IntptrTy);
 
if (ClDebugNonzeroLabels) {
         Instruction *Pos;
         if (Instruction *I = dyn_cast<Instruction>(V))
           Pos = I->getNextNode();
         else
           Pos = &DFSF.F->getEntryBlock().front();
         while (isa<PHINode>(Pos) || isa<AllocaInst>(Pos))
           Pos = Pos->getNextNode();
         IRBuilder<> IRB(Pos);
-        Value *Ne = IRB.CreateICmpNE(V, DFSF.DFS.ZeroShadow);
+        Value *Ne = IRB.CreateICmpNE(V, DFSF.DFS.ZeroPrimitiveShadow);
         BranchInst *BI = cast<BranchInst>(SplitBlockAndInsertIfThen(
             Ne, Pos, /*Unreachable=*/false, ColdCallWeights));
         IRBuilder<> ThenIRB(BI);
         ThenIRB.CreateCall(DFSF.DFS.DFSanNonzeroLabelFn, {});
       }
     }
   }
 
   return Changed || !FnsToInstrument.empty() ||
          M.global_size() != InitialGlobalSize || M.size() != InitialModuleSize;
 }
 
 Value *DFSanFunction::getArgTLS(unsigned Idx, Instruction *Pos) {
   IRBuilder<> IRB(Pos);
-  return IRB.CreateConstGEP2_64(ArrayType::get(DFS.ShadowTy, 64), DFS.ArgTLS, 0,
-                                Idx);
+  return IRB.CreateConstGEP2_64(ArrayType::get(DFS.PrimitiveShadowTy, 64),
+                                DFS.ArgTLS, 0, Idx);
 }
 
 Value *DFSanFunction::getShadow(Value *V) {
   if (!isa<Argument>(V) && !isa<Instruction>(V))
-    return DFS.ZeroShadow;
+    return DFS.ZeroPrimitiveShadow;
   Value *&Shadow = ValShadowMap[V];
   if (!Shadow) {
     if (Argument *A = dyn_cast<Argument>(V)) {
       if (IsNativeABI)
-        return DFS.ZeroShadow;
+        return DFS.ZeroPrimitiveShadow;
       switch (IA) {
       case DataFlowSanitizer::IA_TLS: {
         Value *ArgTLSPtr = DFS.ArgTLS;
         Instruction *ArgTLSPos =
             DFS.ArgTLS ? &*F->getEntryBlock().begin()
                        : cast<Instruction>(ArgTLSPtr)->getNextNode();
         IRBuilder<> IRB(ArgTLSPos);
-        Shadow =
-            IRB.CreateLoad(DFS.ShadowTy, getArgTLS(A->getArgNo(), ArgTLSPos));
+        Shadow = IRB.CreateLoad(DFS.PrimitiveShadowTy,
+                                getArgTLS(A->getArgNo(), ArgTLSPos));
         break;
       }
       case DataFlowSanitizer::IA_Args: {
         unsigned ArgIdx = A->getArgNo() + F->arg_size() / 2;
         Function::arg_iterator i = F->arg_begin();
         while (ArgIdx--)
           ++i;
         Shadow = &*i;
-        assert(Shadow->getType() == DFS.ShadowTy);
+        assert(Shadow->getType() == DFS.PrimitiveShadowTy);
         break;
       }
       }
       NonZeroChecks.push_back(Shadow);
     } else {
-      Shadow = DFS.ZeroShadow;
+      Shadow = DFS.ZeroPrimitiveShadow;
     }
   }
   return Shadow;
 }
 
 void DFSanFunction::setShadow(Instruction *I, Value *Shadow) {
   assert(!ValShadowMap.count(I));
-  assert(Shadow->getType() == DFS.ShadowTy);
+  assert(Shadow->getType() == DFS.PrimitiveShadowTy);
   ValShadowMap[I] = Shadow;
 }
 
 Value *DataFlowSanitizer::getShadowAddress(Value *Addr, Instruction *Pos) {
   assert(Addr != RetvalTLS && "Reinstrumenting?");
   IRBuilder<> IRB(Pos);
   Value *ShadowPtrMaskValue;
   if (DFSanRuntimeShadowMask)
     ShadowPtrMaskValue = IRB.CreateLoad(IntptrTy, ExternalShadowMask);
   else
     ShadowPtrMaskValue = ShadowPtrMask;
   return IRB.CreateIntToPtr(
       IRB.CreateMul(
           IRB.CreateAnd(IRB.CreatePtrToInt(Addr, IntptrTy),
                         IRB.CreatePtrToInt(ShadowPtrMaskValue, IntptrTy)),
           ShadowPtrMul),
-      ShadowPtrTy);
+      PrimitiveShadowPtrTy);
 }
 
 // Generates IR to compute the union of the two given shadows, inserting it
 // before Pos.  Returns the computed union Value.
 Value *DFSanFunction::combineShadows(Value *V1, Value *V2, Instruction *Pos) {
-  if (V1 == DFS.ZeroShadow)
+  if (V1 == DFS.ZeroPrimitiveShadow)
     return V2;
-  if (V2 == DFS.ZeroShadow)
+  if (V2 == DFS.ZeroPrimitiveShadow)
     return V1;
   if (V1 == V2)
     return V1;
 
   auto V1Elems = ShadowElements.find(V1);
   auto V2Elems = ShadowElements.find(V2);
   if (V1Elems != ShadowElements.end() && V2Elems != ShadowElements.end()) {
     if (std::includes(V1Elems->second.begin(), V1Elems->second.end(),
BranchInst *BI = cast<BranchInst>(SplitBlockAndInsertIfThen(
         Ne, Pos, /*Unreachable=*/false, DFS.ColdCallWeights, &DT));
     IRBuilder<> ThenIRB(BI);
     CallInst *Call = ThenIRB.CreateCall(DFS.DFSanUnionFn, {V1, V2});
     Call->addAttribute(AttributeList::ReturnIndex, Attribute::ZExt);
     Call->addParamAttr(0, Attribute::ZExt);
     Call->addParamAttr(1, Attribute::ZExt);
 
     BasicBlock *Tail = BI->getSuccessor(0);
-    PHINode *Phi = PHINode::Create(DFS.ShadowTy, 2, "", &Tail->front());
+    PHINode *Phi =
+        PHINode::Create(DFS.PrimitiveShadowTy, 2, "", &Tail->front());
     Phi->addIncoming(Call, Call->getParent());
     Phi->addIncoming(V1, Head);
 
     CCS.Block = Tail;
     CCS.Shadow = Phi;
   }
 
   std::set<Value *> UnionElems;
Value *DFSanFunction::combineShadows(Value *V1, Value *V2, Instruction *Pos) {
   return CCS.Shadow;
 }
 
 // A convenience function which folds the shadows of each of the operands
 // of the provided instruction Inst, inserting the IR before Inst.  Returns
 // the computed union Value.
 Value *DFSanFunction::combineOperandShadows(Instruction *Inst) {
   if (Inst->getNumOperands() == 0)
-    return DFS.ZeroShadow;
+    return DFS.ZeroPrimitiveShadow;
 
   Value *Shadow = getShadow(Inst->getOperand(0));
   for (unsigned i = 1, n = Inst->getNumOperands(); i != n; ++i) {
     Shadow = combineShadows(Shadow, getShadow(Inst->getOperand(i)), Inst);
   }
   return Shadow;
 }
 
 Value *DFSanVisitor::visitOperandShadowInst(Instruction &I) {
   Value *CombinedShadow = DFSF.combineOperandShadows(&I);
   DFSF.setShadow(&I, CombinedShadow);
   return CombinedShadow;
 }
 
 // Generates IR to load shadow corresponding to bytes [Addr, Addr+Size), where
 // Addr has alignment Align, and take the union of each of those shadows.
 Value *DFSanFunction::loadShadow(Value *Addr, uint64_t Size, uint64_t Align,
                                  Instruction *Pos) {
   if (AllocaInst *AI = dyn_cast<AllocaInst>(Addr)) {
     const auto i = AllocaShadowMap.find(AI);
     if (i != AllocaShadowMap.end()) {
       IRBuilder<> IRB(Pos);
-      return IRB.CreateLoad(DFS.ShadowTy, i->second);
+      return IRB.CreateLoad(DFS.PrimitiveShadowTy, i->second);
     }
   }
 
   const llvm::Align ShadowAlign(Align * DFS.ShadowWidthBytes);
   SmallVector<const Value *, 2> Objs;
   getUnderlyingObjects(Addr, Objs);
   bool AllConstants = true;
   for (const Value *Obj : Objs) {
     if (isa<Function>(Obj) || isa<BlockAddress>(Obj))
       continue;
     if (isa<GlobalVariable>(Obj) && cast<GlobalVariable>(Obj)->isConstant())
       continue;
 
     AllConstants = false;
     break;
   }
   if (AllConstants)
-    return DFS.ZeroShadow;
+    return DFS.ZeroPrimitiveShadow;
 
   Value *ShadowAddr = DFS.getShadowAddress(Addr, Pos);
   switch (Size) {
   case 0:
-    return DFS.ZeroShadow;
+    return DFS.ZeroPrimitiveShadow;
   case 1: {
-    LoadInst *LI = new LoadInst(DFS.ShadowTy, ShadowAddr, "", Pos);
+    LoadInst *LI = new LoadInst(DFS.PrimitiveShadowTy, ShadowAddr, "", Pos);
     LI->setAlignment(ShadowAlign);
     return LI;
   }
   case 2: {
     IRBuilder<> IRB(Pos);
-    Value *ShadowAddr1 = IRB.CreateGEP(DFS.ShadowTy, ShadowAddr,
+    Value *ShadowAddr1 = IRB.CreateGEP(DFS.PrimitiveShadowTy, ShadowAddr,
                                        ConstantInt::get(DFS.IntptrTy, 1));
     return combineShadows(
-        IRB.CreateAlignedLoad(DFS.ShadowTy, ShadowAddr, ShadowAlign),
-        IRB.CreateAlignedLoad(DFS.ShadowTy, ShadowAddr1, ShadowAlign), Pos);
+        IRB.CreateAlignedLoad(DFS.PrimitiveShadowTy, ShadowAddr, ShadowAlign),
+        IRB.CreateAlignedLoad(DFS.PrimitiveShadowTy, ShadowAddr1, ShadowAlign),
+        Pos);
   }
   }
 
   if (ClFast16Labels && Size % (64 / DFS.ShadowWidthBits) == 0) {
     // First OR all the WideShadows, then OR individual shadows within the
     // combined WideShadow.  This is fewer instructions than ORing shadows
     // individually.
     IRBuilder<> IRB(Pos);
     Value *WideAddr =
         IRB.CreateBitCast(ShadowAddr, Type::getInt64PtrTy(*DFS.Ctx));
     Value *CombinedWideShadow =
         IRB.CreateAlignedLoad(IRB.getInt64Ty(), WideAddr, ShadowAlign);
     for (uint64_t Ofs = 64 / DFS.ShadowWidthBits; Ofs != Size;
          Ofs += 64 / DFS.ShadowWidthBits) {
       WideAddr = IRB.CreateGEP(Type::getInt64Ty(*DFS.Ctx), WideAddr,
                                ConstantInt::get(DFS.IntptrTy, 1));
       Value *NextWideShadow =
           IRB.CreateAlignedLoad(IRB.getInt64Ty(), WideAddr, ShadowAlign);
       CombinedWideShadow = IRB.CreateOr(CombinedWideShadow, NextWideShadow);
     }
     for (unsigned Width = 32; Width >= DFS.ShadowWidthBits; Width >>= 1) {
       Value *ShrShadow = IRB.CreateLShr(CombinedWideShadow, Width);
       CombinedWideShadow = IRB.CreateOr(CombinedWideShadow, ShrShadow);
     }
-    return IRB.CreateTrunc(CombinedWideShadow, DFS.ShadowTy);
+    return IRB.CreateTrunc(CombinedWideShadow, DFS.PrimitiveShadowTy);
   }
   if (!AvoidNewBlocks && Size % (64 / DFS.ShadowWidthBits) == 0) {
     // Fast path for the common case where each byte has identical shadow: load
     // shadow 64 bits at a time, fall out to a __dfsan_union_load call if any
     // shadow is non-equal.
     BasicBlock *FallbackBB = BasicBlock::Create(*DFS.Ctx, "", F);
     IRBuilder<> FallbackIRB(FallbackBB);
     CallInst *FallbackCall = FallbackIRB.CreateCall(
         DFS.DFSanUnionLoadFn,
         {ShadowAddr, ConstantInt::get(DFS.IntptrTy, Size)});
     FallbackCall->addAttribute(AttributeList::ReturnIndex, Attribute::ZExt);
 
     // Compare each of the shadows stored in the loaded 64 bits to each other,
     // by computing (WideShadow rotl ShadowWidthBits) == WideShadow.
     IRBuilder<> IRB(Pos);
     Value *WideAddr =
         IRB.CreateBitCast(ShadowAddr, Type::getInt64PtrTy(*DFS.Ctx));
     Value *WideShadow =
         IRB.CreateAlignedLoad(IRB.getInt64Ty(), WideAddr, ShadowAlign);
-    Value *TruncShadow = IRB.CreateTrunc(WideShadow, DFS.ShadowTy);
+    Value *TruncShadow = IRB.CreateTrunc(WideShadow, DFS.PrimitiveShadowTy);
     Value *ShlShadow = IRB.CreateShl(WideShadow, DFS.ShadowWidthBits);
     Value *ShrShadow = IRB.CreateLShr(WideShadow, 64 - DFS.ShadowWidthBits);
     Value *RotShadow = IRB.CreateOr(ShlShadow, ShrShadow);
     Value *ShadowsEq = IRB.CreateICmpEQ(WideShadow, RotShadow);
 
     BasicBlock *Head = Pos->getParent();
     BasicBlock *Tail = Head->splitBasicBlock(Pos->getIterator());
 
for (uint64_t Ofs = 64 / DFS.ShadowWidthBits; Ofs != Size;
                                                         WideAddr, ShadowAlign);
       ShadowsEq = NextIRB.CreateICmpEQ(WideShadow, NextWideShadow);
       LastBr->setSuccessor(0, NextBB);
       LastBr = NextIRB.CreateCondBr(ShadowsEq, FallbackBB, FallbackBB);
     }
 
     LastBr->setSuccessor(0, Tail);
     FallbackIRB.CreateBr(Tail);
-    PHINode *Shadow = PHINode::Create(DFS.ShadowTy, 2, "", &Tail->front());
+    PHINode *Shadow =
+        PHINode::Create(DFS.PrimitiveShadowTy, 2, "", &Tail->front());
     Shadow->addIncoming(FallbackCall, FallbackBB);
     Shadow->addIncoming(TruncShadow, LastBr->getParent());
     return Shadow;
   }
 
   IRBuilder<> IRB(Pos);
   FunctionCallee &UnionLoadFn =
       ClFast16Labels ? DFS.DFSanUnionLoadFast16LabelsFn : DFS.DFSanUnionLoadFn;
   CallInst *FallbackCall = IRB.CreateCall(
       UnionLoadFn, {ShadowAddr, ConstantInt::get(DFS.IntptrTy, Size)});
   FallbackCall->addAttribute(AttributeList::ReturnIndex, Attribute::ZExt);
   return FallbackCall;
 }
 
 void DFSanVisitor::visitLoadInst(LoadInst &LI) {
   auto &DL = LI.getModule()->getDataLayout();
   uint64_t Size = DL.getTypeStoreSize(LI.getType());
   if (Size == 0) {
-    DFSF.setShadow(&LI, DFSF.DFS.ZeroShadow);
+    DFSF.setShadow(&LI, DFSF.DFS.ZeroPrimitiveShadow);
     return;
   }
 
   Align Alignment = ClPreserveAlignment ? LI.getAlign() : Align(1);
   Value *Shadow =
       DFSF.loadShadow(LI.getPointerOperand(), Size, Alignment.value(), &LI);
   if (ClCombinePointerLabelsOnLoad) {
     Value *PtrShadow = DFSF.getShadow(LI.getPointerOperand());
     Shadow = DFSF.combineShadows(Shadow, PtrShadow, &LI);
   }
-  if (Shadow != DFSF.DFS.ZeroShadow)
+  if (Shadow != DFSF.DFS.ZeroPrimitiveShadow)
     DFSF.NonZeroChecks.push_back(Shadow);
 
   DFSF.setShadow(&LI, Shadow);
   if (ClEventCallbacks) {
     IRBuilder<> IRB(&LI);
     Value *Addr8 = IRB.CreateBitCast(LI.getPointerOperand(), DFSF.DFS.Int8Ptr);
     IRB.CreateCall(DFSF.DFS.DFSanLoadCallbackFn, {Shadow, Addr8});
   }
 }
 
 void DFSanFunction::storeShadow(Value *Addr, uint64_t Size, Align Alignment,
                                 Value *Shadow, Instruction *Pos) {
   if (AllocaInst *AI = dyn_cast<AllocaInst>(Addr)) {
     const auto i = AllocaShadowMap.find(AI);
     if (i != AllocaShadowMap.end()) {
       IRBuilder<> IRB(Pos);
       IRB.CreateStore(Shadow, i->second);
       return;
     }
   }
 
   const Align ShadowAlign(Alignment.value() * DFS.ShadowWidthBytes);
   IRBuilder<> IRB(Pos);
   Value *ShadowAddr = DFS.getShadowAddress(Addr, Pos);
-  if (Shadow == DFS.ZeroShadow) {
+  if (Shadow == DFS.ZeroPrimitiveShadow) {
     IntegerType *ShadowTy =
         IntegerType::get(*DFS.Ctx, Size * DFS.ShadowWidthBits);
     Value *ExtZeroShadow = ConstantInt::get(ShadowTy, 0);
     Value *ExtShadowAddr =
         IRB.CreateBitCast(ShadowAddr, PointerType::getUnqual(ShadowTy));
     IRB.CreateAlignedStore(ExtZeroShadow, ExtShadowAddr, ShadowAlign);
     return;
   }
 
   const unsigned ShadowVecSize = 128 / DFS.ShadowWidthBits;
   uint64_t Offset = 0;
   if (Size >= ShadowVecSize) {
-    auto *ShadowVecTy = FixedVectorType::get(DFS.ShadowTy, ShadowVecSize);
+    auto *ShadowVecTy =
+        FixedVectorType::get(DFS.PrimitiveShadowTy, ShadowVecSize);
     Value *ShadowVec = UndefValue::get(ShadowVecTy);
     for (unsigned i = 0; i != ShadowVecSize; ++i) {
       ShadowVec = IRB.CreateInsertElement(
           ShadowVec, Shadow, ConstantInt::get(Type::getInt32Ty(*DFS.Ctx), i));
     }
     Value *ShadowVecAddr =
         IRB.CreateBitCast(ShadowAddr, PointerType::getUnqual(ShadowVecTy));
     do {
       Value *CurShadowVecAddr =
           IRB.CreateConstGEP1_32(ShadowVecTy, ShadowVecAddr, Offset);
       IRB.CreateAlignedStore(ShadowVec, CurShadowVecAddr, ShadowAlign);
       Size -= ShadowVecSize;
       ++Offset;
     } while (Size >= ShadowVecSize);
     Offset *= ShadowVecSize;
   }
   while (Size > 0) {
     Value *CurShadowAddr =
-        IRB.CreateConstGEP1_32(DFS.ShadowTy, ShadowAddr, Offset);
+        IRB.CreateConstGEP1_32(DFS.PrimitiveShadowTy, ShadowAddr, Offset);
     IRB.CreateAlignedStore(Shadow, CurShadowAddr, ShadowAlign);
     --Size;
     ++Offset;
   }
 }
 
 void DFSanVisitor::visitStoreInst(StoreInst &SI) {
   auto &DL = SI.getModule()->getDataLayout();
if (StoreInst *SI = dyn_cast<StoreInst>(U)) {
         continue;
     }
 
     AllLoadsStores = false;
     break;
   }
   if (AllLoadsStores) {
     IRBuilder<> IRB(&I);
-    DFSF.AllocaShadowMap[&I] = IRB.CreateAlloca(DFSF.DFS.ShadowTy);
+    DFSF.AllocaShadowMap[&I] = IRB.CreateAlloca(DFSF.DFS.PrimitiveShadowTy);
   }
-  DFSF.setShadow(&I, DFSF.DFS.ZeroShadow);
+  DFSF.setShadow(&I, DFSF.DFS.ZeroPrimitiveShadow);
 }
 
 void DFSanVisitor::visitSelectInst(SelectInst &I) {
   Value *CondShadow = DFSF.getShadow(I.getCondition());
   Value *TrueShadow = DFSF.getShadow(I.getTrueValue());
   Value *FalseShadow = DFSF.getShadow(I.getFalseValue());
   Value *ShadowSel = nullptr;
 
DenseMap<Value *, Function *>::iterator i =
       DFSF.DFS.UnwrappedFnMap.find(CB.getCalledOperand());
   if (i != DFSF.DFS.UnwrappedFnMap.end()) {
     Function *F = i->second;
     switch (DFSF.DFS.getWrapperKind(F)) {
     case DataFlowSanitizer::WK_Warning:
       CB.setCalledFunction(F);
       IRB.CreateCall(DFSF.DFS.DFSanUnimplementedFn,
                      IRB.CreateGlobalStringPtr(F->getName()));
-      DFSF.setShadow(&CB, DFSF.DFS.ZeroShadow);
+      DFSF.setShadow(&CB, DFSF.DFS.ZeroPrimitiveShadow);
       return;
     case DataFlowSanitizer::WK_Discard:
       CB.setCalledFunction(F);
-      DFSF.setShadow(&CB, DFSF.DFS.ZeroShadow);
+      DFSF.setShadow(&CB, DFSF.DFS.ZeroPrimitiveShadow);
       return;
     case DataFlowSanitizer::WK_Functional:
       CB.setCalledFunction(F);
       visitOperandShadowInst(CB);
       return;
     case DataFlowSanitizer::WK_Custom:
       // Don't try to handle invokes of custom functions, it's too complicated.
       // Instead, invoke the dfsw$ wrapper, which will in turn call the __dfsw_
case DataFlowSanitizer::WK_Custom:
         }
 
         i = CB.arg_begin();
         const unsigned ShadowArgStart = Args.size();
         for (unsigned n = FT->getNumParams(); n != 0; ++i, --n)
           Args.push_back(DFSF.getShadow(*i));
 
         if (FT->isVarArg()) {
-          auto *LabelVATy = ArrayType::get(DFSF.DFS.ShadowTy,
+          auto *LabelVATy = ArrayType::get(DFSF.DFS.PrimitiveShadowTy,
                                            CB.arg_size() - FT->getNumParams());
           auto *LabelVAAlloca = new AllocaInst(
               LabelVATy, getDataLayout().getAllocaAddrSpace(),
               "labelva", &DFSF.F->getEntryBlock().front());
 
           for (unsigned n = 0; i != CB.arg_end(); ++i, ++n) {
             auto LabelVAPtr = IRB.CreateStructGEP(LabelVATy, LabelVAAlloca, n);
             IRB.CreateStore(DFSF.getShadow(*i), LabelVAPtr);
           }
 
           Args.push_back(IRB.CreateStructGEP(LabelVATy, LabelVAAlloca, 0));
         }
 
         if (!FT->getReturnType()->isVoidTy()) {
           if (!DFSF.LabelReturnAlloca) {
             DFSF.LabelReturnAlloca =
-              new AllocaInst(DFSF.DFS.ShadowTy,
+                new AllocaInst(DFSF.DFS.PrimitiveShadowTy,
                                getDataLayout().getAllocaAddrSpace(),
                                "labelreturn", &DFSF.F->getEntryBlock().front());
           }
           Args.push_back(DFSF.LabelReturnAlloca);
         }
 
         for (i = CB.arg_begin() + FT->getNumParams(); i != CB.arg_end(); ++i)
           Args.push_back(*i);
 
         CallInst *CustomCI = IRB.CreateCall(CustomF, Args);
         CustomCI->setCallingConv(CI->getCallingConv());
         CustomCI->setAttributes(TransformFunctionAttributes(CustomFn,
             CI->getContext(), CI->getAttributes()));
 
         // Update the parameter attributes of the custom call instruction to
         // zero extend the shadow parameters. This is required for targets
         // which consider ShadowTy an illegal type.
         for (unsigned n = 0; n < FT->getNumParams(); n++) {
           const unsigned ArgNo = ShadowArgStart + n;
-          if (CustomCI->getArgOperand(ArgNo)->getType() == DFSF.DFS.ShadowTy)
+          if (CustomCI->getArgOperand(ArgNo)->getType() ==
+              DFSF.DFS.PrimitiveShadowTy)
             CustomCI->addParamAttr(ArgNo, Attribute::ZExt);
         }
 
         if (!FT->getReturnType()->isVoidTy()) {
-          LoadInst *LabelLoad =
-              IRB.CreateLoad(DFSF.DFS.ShadowTy, DFSF.LabelReturnAlloca);
+          LoadInst *LabelLoad = IRB.CreateLoad(DFSF.DFS.PrimitiveShadowTy,
+                                               DFSF.LabelReturnAlloca);
           DFSF.setShadow(CustomCI, LabelLoad);
         }
 
         CI->replaceAllUsesWith(CustomCI);
         CI->eraseFromParent();
         return;
       }
       break;
if (InvokeInst *II = dyn_cast<InvokeInst>(&CB)) {
       }
     } else {
       assert(CB.getIterator() != CB.getParent()->end());
       Next = CB.getNextNode();
     }
 
     if (DFSF.DFS.getInstrumentedABI() == DataFlowSanitizer::IA_TLS) {
       IRBuilder<> NextIRB(Next);
-      LoadInst *LI = NextIRB.CreateLoad(DFSF.DFS.ShadowTy, DFSF.DFS.RetvalTLS);
+      LoadInst *LI =
+          NextIRB.CreateLoad(DFSF.DFS.PrimitiveShadowTy, DFSF.DFS.RetvalTLS);
       DFSF.SkipInsts.insert(LI);
       DFSF.setShadow(&CB, LI);
       DFSF.NonZeroChecks.push_back(LI);
     }
   }
 
   // Do all instrumentation for IA_Args down here to defer tampering with the
   // CFG in a way that SplitEdge may be able to detect.
   if (DFSF.DFS.getInstrumentedABI() == DataFlowSanitizer::IA_Args) {
     FunctionType *NewFT = DFSF.DFS.getArgsFunctionType(FT);
     Value *Func =
         IRB.CreateBitCast(CB.getCalledOperand(), PointerType::getUnqual(NewFT));
     std::vector<Value *> Args;
 
     auto i = CB.arg_begin(), E = CB.arg_end();
     for (unsigned n = FT->getNumParams(); n != 0; ++i, --n)
       Args.push_back(*i);
 
     i = CB.arg_begin();
     for (unsigned n = FT->getNumParams(); n != 0; ++i, --n)
       Args.push_back(DFSF.getShadow(*i));
 
     if (FT->isVarArg()) {
       unsigned VarArgSize = CB.arg_size() - FT->getNumParams();
-      ArrayType *VarArgArrayTy = ArrayType::get(DFSF.DFS.ShadowTy, VarArgSize);
+      ArrayType *VarArgArrayTy =
+          ArrayType::get(DFSF.DFS.PrimitiveShadowTy, VarArgSize);
       AllocaInst *VarArgShadow =
         new AllocaInst(VarArgArrayTy, getDataLayout().getAllocaAddrSpace(),
                        "", &DFSF.F->getEntryBlock().front());
       Args.push_back(IRB.CreateConstGEP2_32(VarArgArrayTy, VarArgShadow, 0, 0));
       for (unsigned n = 0; i != E; ++i, ++n) {
         IRB.CreateStore(
             DFSF.getShadow(*i),
             IRB.CreateConstGEP2_32(VarArgArrayTy, VarArgShadow, 0, n));
if (Next) {
       CB.replaceAllUsesWith(ExVal);
     }
 
     CB.eraseFromParent();
   }
 }
 
 void DFSanVisitor::visitPHINode(PHINode &PN) {
-  PHINode *ShadowPN =
-      PHINode::Create(DFSF.DFS.ShadowTy, PN.getNumIncomingValues(), "", &PN);
+  PHINode *ShadowPN = PHINode::Create(DFSF.DFS.PrimitiveShadowTy,
+                                      PN.getNumIncomingValues(), "", &PN);
 
   // Give the shadow phi node valid predecessors to fool SplitEdge into working.
-  Value *UndefShadow = UndefValue::get(DFSF.DFS.ShadowTy);
+  Value *UndefShadow = UndefValue::get(DFSF.DFS.PrimitiveShadowTy);
   for (PHINode::block_iterator i = PN.block_begin(), e = PN.block_end(); i != e;
        ++i) {
     ShadowPN->addIncoming(UndefShadow, *i);
   }
 
   DFSF.PHIFixups.push_back(std::make_pair(&PN, ShadowPN));
   DFSF.setShadow(&PN, ShadowPN);
 }