Revert "Change memcpy/memset/memmove to have dest and source alignments."
[oota-llvm.git] / lib / Transforms / Instrumentation / DataFlowSanitizer.cpp
index e3a4b383be2ade30a69854e502b7d948c847eb0b..21ef3207e899dbad8f740946165c16e6d8e68c8a 100644 (file)
 #include "llvm/ADT/DenseSet.h"
 #include "llvm/ADT/DepthFirstIterator.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/Triple.h"
 #include "llvm/Analysis/ValueTracking.h"
 #include "llvm/IR/Dominators.h"
+#include "llvm/IR/DebugInfo.h"
 #include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/InlineAsm.h"
 #include "llvm/IR/InstVisitor.h"
 
 using namespace llvm;
 
+// VMA size definition for architecture that support multiple sizes.
+// AArch64 has 3 VMA sizes: 39, 42 and 48.
+#ifndef SANITIZER_AARCH64_VMA
+# define SANITIZER_AARCH64_VMA 39
+#else
+# if SANITIZER_AARCH64_VMA != 39 && SANITIZER_AARCH64_VMA != 42
+#  error "invalid SANITIZER_AARCH64_VMA size"
+# endif
+#endif
+
 // The -dfsan-preserve-alignment flag controls whether this pass assumes that
 // alignment requirements provided by the input IR are correct.  For example,
 // if the input IR contains a load with alignment 8, this flag will cause
@@ -81,14 +93,14 @@ static cl::opt<bool> ClPreserveAlignment(
     cl::desc("respect alignment requirements provided by input IR"), cl::Hidden,
     cl::init(false));
 
-// The ABI list file controls how shadow parameters are passed.  The pass treats
+// The ABI list files control how shadow parameters are passed. The pass treats
 // every function labelled "uninstrumented" in the ABI list file as conforming
 // to the "native" (i.e. unsanitized) ABI.  Unless the ABI list contains
 // additional annotations for those functions, a call to one of those functions
 // will produce a warning message, as the labelling behaviour of the function is
 // unknown.  The other supported annotations are "functional" and "discard",
 // which are described below under DataFlowSanitizer::WrapperKind.
-static cl::opt<std::string> ClABIListFile(
+static cl::list<std::string> ClABIListFiles(
     "dfsan-abilist",
     cl::desc("File listing native ABI functions and how the pass treats them"),
     cl::Hidden);
@@ -139,11 +151,13 @@ class DFSanABIList {
   std::unique_ptr<SpecialCaseList> SCL;
 
  public:
-  DFSanABIList(SpecialCaseList *SCL) : SCL(SCL) {}
+  DFSanABIList() {}
+
+  void set(std::unique_ptr<SpecialCaseList> List) { SCL = std::move(List); }
 
   /// Returns whether either this function or its source file are listed in the
   /// given category.
-  bool isIn(const Function &F, const StringRef Category) const {
+  bool isIn(const Function &F, StringRef Category) const {
     return isIn(*F.getParent(), Category) ||
            SCL->inSection("fun", F.getName(), Category);
   }
@@ -152,7 +166,7 @@ class DFSanABIList {
   ///
   /// If GA aliases a function, the alias's name is matched as a function name
   /// would be.  Similarly, aliases of globals are matched like globals.
-  bool isIn(const GlobalAlias &GA, const StringRef Category) const {
+  bool isIn(const GlobalAlias &GA, StringRef Category) const {
     if (isIn(*GA.getParent(), Category))
       return true;
 
@@ -164,7 +178,7 @@ class DFSanABIList {
   }
 
   /// Returns whether this module is listed in the given category.
-  bool isIn(const Module &M, const StringRef Category) const {
+  bool isIn(const Module &M, StringRef Category) const {
     return SCL->inSection("src", M.getModuleIdentifier(), Category);
   }
 };
@@ -213,7 +227,6 @@ class DataFlowSanitizer : public ModulePass {
     WK_Custom
   };
 
-  const DataLayout *DL;
   Module *Mod;
   LLVMContext *Ctx;
   IntegerType *ShadowTy;
@@ -233,12 +246,14 @@ class DataFlowSanitizer : public ModulePass {
   FunctionType *DFSanUnimplementedFnTy;
   FunctionType *DFSanSetLabelFnTy;
   FunctionType *DFSanNonzeroLabelFnTy;
+  FunctionType *DFSanVarargWrapperFnTy;
   Constant *DFSanUnionFn;
   Constant *DFSanCheckedUnionFn;
   Constant *DFSanUnionLoadFn;
   Constant *DFSanUnimplementedFn;
   Constant *DFSanSetLabelFn;
   Constant *DFSanNonzeroLabelFn;
+  Constant *DFSanVarargWrapperFn;
   MDNode *ColdCallWeights;
   DFSanABIList ABIList;
   DenseMap<Value *, Function *> UnwrappedFnMap;
@@ -259,9 +274,9 @@ class DataFlowSanitizer : public ModulePass {
   Constant *getOrBuildTrampolineFunction(FunctionType *FT, StringRef FName);
 
  public:
-  DataFlowSanitizer(StringRef ABIListFile = StringRef(),
-                    void *(*getArgTLS)() = nullptr,
-                    void *(*getRetValTLS)() = nullptr);
+  DataFlowSanitizer(
+      const std::vector<std::string> &ABIListFiles = std::vector<std::string>(),
+      void *(*getArgTLS)() = nullptr, void *(*getRetValTLS)() = nullptr);
   static char ID;
   bool doInitialization(Module &M) override;
   bool runOnModule(Module &M) override;
@@ -346,25 +361,26 @@ char DataFlowSanitizer::ID;
 INITIALIZE_PASS(DataFlowSanitizer, "dfsan",
                 "DataFlowSanitizer: dynamic data flow analysis.", false, false)
 
-ModulePass *llvm::createDataFlowSanitizerPass(StringRef ABIListFile,
-                                              void *(*getArgTLS)(),
-                                              void *(*getRetValTLS)()) {
-  return new DataFlowSanitizer(ABIListFile, getArgTLS, getRetValTLS);
+ModulePass *
+llvm::createDataFlowSanitizerPass(const std::vector<std::string> &ABIListFiles,
+                                  void *(*getArgTLS)(),
+                                  void *(*getRetValTLS)()) {
+  return new DataFlowSanitizer(ABIListFiles, getArgTLS, getRetValTLS);
 }
 
-DataFlowSanitizer::DataFlowSanitizer(StringRef ABIListFile,
-                                     void *(*getArgTLS)(),
-                                     void *(*getRetValTLS)())
-    : ModulePass(ID), GetArgTLSPtr(getArgTLS), GetRetvalTLSPtr(getRetValTLS),
-      ABIList(SpecialCaseList::createOrDie(ABIListFile.empty() ? ClABIListFile
-                                                               : ABIListFile)) {
+DataFlowSanitizer::DataFlowSanitizer(
+    const std::vector<std::string> &ABIListFiles, void *(*getArgTLS)(),
+    void *(*getRetValTLS)())
+    : ModulePass(ID), GetArgTLSPtr(getArgTLS), GetRetvalTLSPtr(getRetValTLS) {
+  std::vector<std::string> AllABIListFiles(std::move(ABIListFiles));
+  AllABIListFiles.insert(AllABIListFiles.end(), ClABIListFiles.begin(),
+                         ClABIListFiles.end());
+  ABIList.set(SpecialCaseList::createOrDie(AllABIListFiles));
 }
 
 FunctionType *DataFlowSanitizer::getArgsFunctionType(FunctionType *T) {
-  llvm::SmallVector<Type *, 4> ArgTypes;
-  std::copy(T->param_begin(), T->param_end(), std::back_inserter(ArgTypes));
-  for (unsigned i = 0, e = T->getNumParams(); i != e; ++i)
-    ArgTypes.push_back(ShadowTy);
+  llvm::SmallVector<Type *, 4> ArgTypes(T->param_begin(), T->param_end());
+  ArgTypes.append(T->getNumParams(), ShadowTy);
   if (T->isVarArg())
     ArgTypes.push_back(ShadowPtrTy);
   Type *RetType = T->getReturnType();
@@ -377,9 +393,8 @@ FunctionType *DataFlowSanitizer::getTrampolineFunctionType(FunctionType *T) {
   assert(!T->isVarArg());
   llvm::SmallVector<Type *, 4> ArgTypes;
   ArgTypes.push_back(T->getPointerTo());
-  std::copy(T->param_begin(), T->param_end(), std::back_inserter(ArgTypes));
-  for (unsigned i = 0, e = T->getNumParams(); i != e; ++i)
-    ArgTypes.push_back(ShadowTy);
+  ArgTypes.append(T->param_begin(), T->param_end());
+  ArgTypes.append(T->getNumParams(), ShadowTy);
   Type *RetType = T->getReturnType();
   if (!RetType->isVoidTy())
     ArgTypes.push_back(ShadowPtrTy);
@@ -387,7 +402,6 @@ FunctionType *DataFlowSanitizer::getTrampolineFunctionType(FunctionType *T) {
 }
 
 FunctionType *DataFlowSanitizer::getCustomFunctionType(FunctionType *T) {
-  assert(!T->isVarArg());
   llvm::SmallVector<Type *, 4> ArgTypes;
   for (FunctionType::param_iterator i = T->param_begin(), e = T->param_end();
        i != e; ++i) {
@@ -402,26 +416,43 @@ FunctionType *DataFlowSanitizer::getCustomFunctionType(FunctionType *T) {
   }
   for (unsigned i = 0, e = T->getNumParams(); i != e; ++i)
     ArgTypes.push_back(ShadowTy);
+  if (T->isVarArg())
+    ArgTypes.push_back(ShadowPtrTy);
   Type *RetType = T->getReturnType();
   if (!RetType->isVoidTy())
     ArgTypes.push_back(ShadowPtrTy);
-  return FunctionType::get(T->getReturnType(), ArgTypes, false);
+  return FunctionType::get(T->getReturnType(), ArgTypes, T->isVarArg());
 }
 
 bool DataFlowSanitizer::doInitialization(Module &M) {
-  DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
-  if (!DLP)
-    report_fatal_error("data layout missing");
-  DL = &DLP->getDataLayout();
+  llvm::Triple TargetTriple(M.getTargetTriple());
+  bool IsX86_64 = TargetTriple.getArch() == llvm::Triple::x86_64;
+  bool IsMIPS64 = TargetTriple.getArch() == llvm::Triple::mips64 ||
+                  TargetTriple.getArch() == llvm::Triple::mips64el;
+  bool IsAArch64 = TargetTriple.getArch() == llvm::Triple::aarch64 ||
+                   TargetTriple.getArch() == llvm::Triple::aarch64_be;
+
+  const DataLayout &DL = M.getDataLayout();
 
   Mod = &M;
   Ctx = &M.getContext();
   ShadowTy = IntegerType::get(*Ctx, ShadowWidth);
   ShadowPtrTy = PointerType::getUnqual(ShadowTy);
-  IntptrTy = DL->getIntPtrType(*Ctx);
+  IntptrTy = DL.getIntPtrType(*Ctx);
   ZeroShadow = ConstantInt::getSigned(ShadowTy, 0);
-  ShadowPtrMask = ConstantInt::getSigned(IntptrTy, ~0x700000000000LL);
   ShadowPtrMul = ConstantInt::getSigned(IntptrTy, ShadowWidth / 8);
+  if (IsX86_64)
+    ShadowPtrMask = ConstantInt::getSigned(IntptrTy, ~0x700000000000LL);
+  else if (IsMIPS64)
+    ShadowPtrMask = ConstantInt::getSigned(IntptrTy, ~0xF000000000LL);
+  else if (IsAArch64)
+#if SANITIZER_AARCH64_VMA == 39
+    ShadowPtrMask = ConstantInt::getSigned(IntptrTy, ~0x7800000000LL);
+#else
+    ShadowPtrMask = ConstantInt::getSigned(IntptrTy, ~0x3c000000000LL);
+#endif
+  else
+    report_fatal_error("unsupported triple");
 
   Type *DFSanUnionArgs[2] = { ShadowTy, ShadowTy };
   DFSanUnionFnTy =
@@ -436,6 +467,8 @@ bool DataFlowSanitizer::doInitialization(Module &M) {
                                         DFSanSetLabelArgs, /*isVarArg=*/false);
   DFSanNonzeroLabelFnTy = FunctionType::get(
       Type::getVoidTy(*Ctx), None, /*isVarArg=*/false);
+  DFSanVarargWrapperFnTy = FunctionType::get(
+      Type::getVoidTy(*Ctx), Type::getInt8PtrTy(*Ctx), /*isVarArg=*/false);
 
   if (GetArgTLSPtr) {
     Type *ArgTLSTy = ArrayType::get(ShadowTy, 64);
@@ -476,7 +509,7 @@ DataFlowSanitizer::WrapperKind DataFlowSanitizer::getWrapperKind(Function *F) {
     return WK_Functional;
   if (ABIList.isIn(*F, "discard"))
     return WK_Discard;
-  if (ABIList.isIn(*F, "custom") && !F->isVarArg())
+  if (ABIList.isIn(*F, "custom"))
     return WK_Custom;
 
   return WK_Warning;
@@ -510,20 +543,31 @@ DataFlowSanitizer::buildWrapperFunction(Function *F, StringRef NewFName,
                                     F->getParent());
   NewF->copyAttributesFrom(F);
   NewF->removeAttributes(
-      AttributeSet::ReturnIndex,
-      AttributeFuncs::typeIncompatible(NewFT->getReturnType(),
-                                       AttributeSet::ReturnIndex));
+    AttributeSet::ReturnIndex,
+    AttributeSet::get(F->getContext(), AttributeSet::ReturnIndex,
+                    AttributeFuncs::typeIncompatible(NewFT->getReturnType())));
 
   BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", NewF);
-  std::vector<Value *> Args;
-  unsigned n = FT->getNumParams();
-  for (Function::arg_iterator ai = NewF->arg_begin(); n != 0; ++ai, --n)
-    Args.push_back(&*ai);
-  CallInst *CI = CallInst::Create(F, Args, "", BB);
-  if (FT->getReturnType()->isVoidTy())
-    ReturnInst::Create(*Ctx, BB);
-  else
-    ReturnInst::Create(*Ctx, CI, BB);
+  if (F->isVarArg()) {
+    NewF->removeAttributes(
+        AttributeSet::FunctionIndex,
+        AttributeSet().addAttribute(*Ctx, AttributeSet::FunctionIndex,
+                                    "split-stack"));
+    CallInst::Create(DFSanVarargWrapperFn,
+                     IRBuilder<>(BB).CreateGlobalStringPtr(F->getName()), "",
+                     BB);
+    new UnreachableInst(*Ctx, BB);
+  } else {
+    std::vector<Value *> Args;
+    unsigned n = FT->getNumParams();
+    for (Function::arg_iterator ai = NewF->arg_begin(); n != 0; ++ai, --n)
+      Args.push_back(&*ai);
+    CallInst *CI = CallInst::Create(F, Args, "", BB);
+    if (FT->getReturnType()->isVoidTy())
+      ReturnInst::Create(*Ctx, BB);
+    else
+      ReturnInst::Create(*Ctx, CI, BB);
+  }
 
   return NewF;
 }
@@ -551,7 +595,7 @@ Constant *DataFlowSanitizer::getOrBuildTrampolineFunction(FunctionType *FT,
     DFSanFunction DFSF(*this, F, /*IsNativeABI=*/true);
     Function::arg_iterator ValAI = F->arg_begin(), ShadowAI = AI; ++ValAI;
     for (unsigned N = FT->getNumParams(); N != 0; ++ValAI, ++ShadowAI, --N)
-      DFSF.ValShadowMap[ValAI] = ShadowAI;
+      DFSF.ValShadowMap[&*ValAI] = &*ShadowAI;
     DFSanVisitor(DFSF).visitCallInst(*CI);
     if (!FT->getReturnType()->isVoidTy())
       new StoreInst(DFSF.getShadow(RI->getReturnValue()),
@@ -562,9 +606,6 @@ Constant *DataFlowSanitizer::getOrBuildTrampolineFunction(FunctionType *FT,
 }
 
 bool DataFlowSanitizer::runOnModule(Module &M) {
-  if (!DL)
-    return false;
-
   if (ABIList.isIn(M, "skip"))
     return false;
 
@@ -612,18 +653,21 @@ bool DataFlowSanitizer::runOnModule(Module &M) {
   }
   DFSanNonzeroLabelFn =
       Mod->getOrInsertFunction("__dfsan_nonzero_label", DFSanNonzeroLabelFnTy);
+  DFSanVarargWrapperFn = Mod->getOrInsertFunction("__dfsan_vararg_wrapper",
+                                                  DFSanVarargWrapperFnTy);
 
   std::vector<Function *> FnsToInstrument;
   llvm::SmallPtrSet<Function *, 2> FnsWithNativeABI;
-  for (Module::iterator i = M.begin(), e = M.end(); i != e; ++i) {
-    if (!i->isIntrinsic() &&
-        i != DFSanUnionFn &&
-        i != DFSanCheckedUnionFn &&
-        i != DFSanUnionLoadFn &&
-        i != DFSanUnimplementedFn &&
-        i != DFSanSetLabelFn &&
-        i != DFSanNonzeroLabelFn)
-      FnsToInstrument.push_back(&*i);
+  for (Function &i : M) {
+    if (!i.isIntrinsic() &&
+        &i != DFSanUnionFn &&
+        &i != DFSanCheckedUnionFn &&
+        &i != DFSanUnionLoadFn &&
+        &i != DFSanUnimplementedFn &&
+        &i != DFSanSetLabelFn &&
+        &i != DFSanNonzeroLabelFn &&
+        &i != DFSanVarargWrapperFn)
+      FnsToInstrument.push_back(&i);
   }
 
   // Give function aliases prefixes when necessary, and build wrappers where the
@@ -674,14 +718,14 @@ bool DataFlowSanitizer::runOnModule(Module &M) {
         Function *NewF = Function::Create(NewFT, F.getLinkage(), "", &M);
         NewF->copyAttributesFrom(&F);
         NewF->removeAttributes(
-            AttributeSet::ReturnIndex,
-            AttributeFuncs::typeIncompatible(NewFT->getReturnType(),
-                                             AttributeSet::ReturnIndex));
+          AttributeSet::ReturnIndex,
+          AttributeSet::get(NewF->getContext(), AttributeSet::ReturnIndex,
+                    AttributeFuncs::typeIncompatible(NewFT->getReturnType())));
         for (Function::arg_iterator FArg = F.arg_begin(),
                                     NewFArg = NewF->arg_begin(),
                                     FArgEnd = F.arg_end();
              FArg != FArgEnd; ++FArg, ++NewFArg) {
-          FArg->replaceAllUsesWith(NewFArg);
+          FArg->replaceAllUsesWith(&*NewFArg);
         }
         NewF->getBasicBlockList().splice(NewF->begin(), F.getBasicBlockList());
 
@@ -704,11 +748,6 @@ bool DataFlowSanitizer::runOnModule(Module &M) {
       } else {
         addGlobalNamePrefix(&F);
       }
-               // Hopefully, nobody will try to indirectly call a vararg
-               // function... yet.
-    } else if (FT->isVarArg()) {
-      UnwrappedFnMap[&F] = &F;
-      *i = nullptr;
     } else if (!IsZeroArgsVoidRet || getWrapperKind(&F) == WK_Custom) {
       // Build a wrapper function for F.  The wrapper simply calls F, and is
       // added to FnsToInstrument so that any instrumentation according to its
@@ -725,6 +764,7 @@ bool DataFlowSanitizer::runOnModule(Module &M) {
       Value *WrappedFnCst =
           ConstantExpr::getBitCast(NewF, PointerType::getUnqual(FT));
       F.replaceAllUsesWith(WrappedFnCst);
+
       UnwrappedFnMap[WrappedFnCst] = &F;
       *i = NewF;
 
@@ -744,6 +784,11 @@ bool DataFlowSanitizer::runOnModule(Module &M) {
         i = FnsToInstrument.begin() + N;
         e = FnsToInstrument.begin() + Count;
       }
+               // Hopefully, nobody will try to indirectly call a vararg
+               // function... yet.
+    } else if (FT->isVarArg()) {
+      UnwrappedFnMap[&F] = &F;
+      *i = nullptr;
     }
   }
 
@@ -807,7 +852,7 @@ bool DataFlowSanitizer::runOnModule(Module &M) {
         if (Instruction *I = dyn_cast<Instruction>(V))
           Pos = I->getNextNode();
         else
-          Pos = DFSF.F->getEntryBlock().begin();
+          Pos = &DFSF.F->getEntryBlock().front();
         while (isa<PHINode>(Pos) || isa<AllocaInst>(Pos))
           Pos = Pos->getNextNode();
         IRBuilder<> IRB(Pos);
@@ -815,7 +860,7 @@ bool DataFlowSanitizer::runOnModule(Module &M) {
         BranchInst *BI = cast<BranchInst>(SplitBlockAndInsertIfThen(
             Ne, Pos, /*Unreachable=*/false, ColdCallWeights));
         IRBuilder<> ThenIRB(BI);
-        ThenIRB.CreateCall(DFSF.DFS.DFSanNonzeroLabelFn);
+        ThenIRB.CreateCall(DFSF.DFS.DFSanNonzeroLabelFn, {});
       }
     }
   }
@@ -829,8 +874,8 @@ Value *DFSanFunction::getArgTLSPtr() {
   if (DFS.ArgTLS)
     return ArgTLSPtr = DFS.ArgTLS;
 
-  IRBuilder<> IRB(F->getEntryBlock().begin());
-  return ArgTLSPtr = IRB.CreateCall(DFS.GetArgTLS);
+  IRBuilder<> IRB(&F->getEntryBlock().front());
+  return ArgTLSPtr = IRB.CreateCall(DFS.GetArgTLS, {});
 }
 
 Value *DFSanFunction::getRetvalTLS() {
@@ -839,8 +884,8 @@ Value *DFSanFunction::getRetvalTLS() {
   if (DFS.RetvalTLS)
     return RetvalTLSPtr = DFS.RetvalTLS;
 
-  IRBuilder<> IRB(F->getEntryBlock().begin());
-  return RetvalTLSPtr = IRB.CreateCall(DFS.GetRetvalTLS);
+  IRBuilder<> IRB(&F->getEntryBlock().front());
+  return RetvalTLSPtr = IRB.CreateCall(DFS.GetRetvalTLS, {});
 }
 
 Value *DFSanFunction::getArgTLS(unsigned Idx, Instruction *Pos) {
@@ -871,7 +916,7 @@ Value *DFSanFunction::getShadow(Value *V) {
         Function::arg_iterator i = F->arg_begin();
         while (ArgIdx--)
           ++i;
-        Shadow = i;
+        Shadow = &*i;
         assert(Shadow->getType() == DFS.ShadowTy);
         break;
       }
@@ -937,7 +982,7 @@ Value *DFSanFunction::combineShadows(Value *V1, Value *V2, Instruction *Pos) {
 
   IRBuilder<> IRB(Pos);
   if (AvoidNewBlocks) {
-    CallInst *Call = IRB.CreateCall2(DFS.DFSanCheckedUnionFn, V1, V2);
+    CallInst *Call = IRB.CreateCall(DFS.DFSanCheckedUnionFn, {V1, V2});
     Call->addAttribute(AttributeSet::ReturnIndex, Attribute::ZExt);
     Call->addAttribute(1, Attribute::ZExt);
     Call->addAttribute(2, Attribute::ZExt);
@@ -950,13 +995,13 @@ Value *DFSanFunction::combineShadows(Value *V1, Value *V2, Instruction *Pos) {
     BranchInst *BI = cast<BranchInst>(SplitBlockAndInsertIfThen(
         Ne, Pos, /*Unreachable=*/false, DFS.ColdCallWeights, &DT));
     IRBuilder<> ThenIRB(BI);
-    CallInst *Call = ThenIRB.CreateCall2(DFS.DFSanUnionFn, V1, V2);
+    CallInst *Call = ThenIRB.CreateCall(DFS.DFSanUnionFn, {V1, V2});
     Call->addAttribute(AttributeSet::ReturnIndex, Attribute::ZExt);
     Call->addAttribute(1, Attribute::ZExt);
     Call->addAttribute(2, Attribute::ZExt);
 
     BasicBlock *Tail = BI->getSuccessor(0);
-    PHINode *Phi = PHINode::Create(DFS.ShadowTy, 2, "", Tail->begin());
+    PHINode *Phi = PHINode::Create(DFS.ShadowTy, 2, "", &Tail->front());
     Phi->addIncoming(Call, Call->getParent());
     Phi->addIncoming(V1, Head);
 
@@ -1014,7 +1059,7 @@ Value *DFSanFunction::loadShadow(Value *Addr, uint64_t Size, uint64_t Align,
 
   uint64_t ShadowAlign = Align * DFS.ShadowWidth / 8;
   SmallVector<Value *, 2> Objs;
-  GetUnderlyingObjects(Addr, Objs, DFS.DL);
+  GetUnderlyingObjects(Addr, Objs, Pos->getModule()->getDataLayout());
   bool AllConstants = true;
   for (SmallVector<Value *, 2>::iterator i = Objs.begin(), e = Objs.end();
        i != e; ++i) {
@@ -1040,8 +1085,8 @@ Value *DFSanFunction::loadShadow(Value *Addr, uint64_t Size, uint64_t Align,
   }
   case 2: {
     IRBuilder<> IRB(Pos);
-    Value *ShadowAddr1 =
-        IRB.CreateGEP(ShadowAddr, ConstantInt::get(DFS.IntptrTy, 1));
+    Value *ShadowAddr1 = IRB.CreateGEP(DFS.ShadowTy, ShadowAddr,
+                                       ConstantInt::get(DFS.IntptrTy, 1));
     return combineShadows(IRB.CreateAlignedLoad(ShadowAddr, ShadowAlign),
                           IRB.CreateAlignedLoad(ShadowAddr1, ShadowAlign), Pos);
   }
@@ -1052,8 +1097,9 @@ Value *DFSanFunction::loadShadow(Value *Addr, uint64_t Size, uint64_t Align,
     // shadow is non-equal.
     BasicBlock *FallbackBB = BasicBlock::Create(*DFS.Ctx, "", F);
     IRBuilder<> FallbackIRB(FallbackBB);
-    CallInst *FallbackCall = FallbackIRB.CreateCall2(
-        DFS.DFSanUnionLoadFn, ShadowAddr, ConstantInt::get(DFS.IntptrTy, Size));
+    CallInst *FallbackCall = FallbackIRB.CreateCall(
+        DFS.DFSanUnionLoadFn,
+        {ShadowAddr, ConstantInt::get(DFS.IntptrTy, Size)});
     FallbackCall->addAttribute(AttributeSet::ReturnIndex, Attribute::ZExt);
 
     // Compare each of the shadows stored in the loaded 64 bits to each other,
@@ -1069,7 +1115,7 @@ Value *DFSanFunction::loadShadow(Value *Addr, uint64_t Size, uint64_t Align,
     Value *ShadowsEq = IRB.CreateICmpEQ(WideShadow, RotShadow);
 
     BasicBlock *Head = Pos->getParent();
-    BasicBlock *Tail = Head->splitBasicBlock(Pos);
+    BasicBlock *Tail = Head->splitBasicBlock(Pos->getIterator());
 
     if (DomTreeNode *OldNode = DT.getNode(Head)) {
       std::vector<DomTreeNode *> Children(OldNode->begin(), OldNode->end());
@@ -1092,7 +1138,8 @@ Value *DFSanFunction::loadShadow(Value *Addr, uint64_t Size, uint64_t Align,
       BasicBlock *NextBB = BasicBlock::Create(*DFS.Ctx, "", F);
       DT.addNewBlock(NextBB, LastBr->getParent());
       IRBuilder<> NextIRB(NextBB);
-      WideAddr = NextIRB.CreateGEP(WideAddr, ConstantInt::get(DFS.IntptrTy, 1));
+      WideAddr = NextIRB.CreateGEP(Type::getInt64Ty(*DFS.Ctx), WideAddr,
+                                   ConstantInt::get(DFS.IntptrTy, 1));
       Value *NextWideShadow = NextIRB.CreateAlignedLoad(WideAddr, ShadowAlign);
       ShadowsEq = NextIRB.CreateICmpEQ(WideShadow, NextWideShadow);
       LastBr->setSuccessor(0, NextBB);
@@ -1108,14 +1155,15 @@ Value *DFSanFunction::loadShadow(Value *Addr, uint64_t Size, uint64_t Align,
   }
 
   IRBuilder<> IRB(Pos);
-  CallInst *FallbackCall = IRB.CreateCall2(
-      DFS.DFSanUnionLoadFn, ShadowAddr, ConstantInt::get(DFS.IntptrTy, Size));
+  CallInst *FallbackCall = IRB.CreateCall(
+      DFS.DFSanUnionLoadFn, {ShadowAddr, ConstantInt::get(DFS.IntptrTy, Size)});
   FallbackCall->addAttribute(AttributeSet::ReturnIndex, Attribute::ZExt);
   return FallbackCall;
 }
 
 void DFSanVisitor::visitLoadInst(LoadInst &LI) {
-  uint64_t Size = DFSF.DFS.DL->getTypeStoreSize(LI.getType());
+  auto &DL = LI.getModule()->getDataLayout();
+  uint64_t Size = DL.getTypeStoreSize(LI.getType());
   if (Size == 0) {
     DFSF.setShadow(&LI, DFSF.DFS.ZeroShadow);
     return;
@@ -1125,7 +1173,7 @@ void DFSanVisitor::visitLoadInst(LoadInst &LI) {
   if (ClPreserveAlignment) {
     Align = LI.getAlignment();
     if (Align == 0)
-      Align = DFSF.DFS.DL->getABITypeAlignment(LI.getType());
+      Align = DL.getABITypeAlignment(LI.getType());
   } else {
     Align = 1;
   }
@@ -1177,7 +1225,8 @@ void DFSanFunction::storeShadow(Value *Addr, uint64_t Size, uint64_t Align,
     Value *ShadowVecAddr =
         IRB.CreateBitCast(ShadowAddr, PointerType::getUnqual(ShadowVecTy));
     do {
-      Value *CurShadowVecAddr = IRB.CreateConstGEP1_32(ShadowVecAddr, Offset);
+      Value *CurShadowVecAddr =
+          IRB.CreateConstGEP1_32(ShadowVecTy, ShadowVecAddr, Offset);
       IRB.CreateAlignedStore(ShadowVec, CurShadowVecAddr, ShadowAlign);
       Size -= ShadowVecSize;
       ++Offset;
@@ -1185,7 +1234,8 @@ void DFSanFunction::storeShadow(Value *Addr, uint64_t Size, uint64_t Align,
     Offset *= ShadowVecSize;
   }
   while (Size > 0) {
-    Value *CurShadowAddr = IRB.CreateConstGEP1_32(ShadowAddr, Offset);
+    Value *CurShadowAddr =
+        IRB.CreateConstGEP1_32(DFS.ShadowTy, ShadowAddr, Offset);
     IRB.CreateAlignedStore(Shadow, CurShadowAddr, ShadowAlign);
     --Size;
     ++Offset;
@@ -1193,8 +1243,8 @@ void DFSanFunction::storeShadow(Value *Addr, uint64_t Size, uint64_t Align,
 }
 
 void DFSanVisitor::visitStoreInst(StoreInst &SI) {
-  uint64_t Size =
-      DFSF.DFS.DL->getTypeStoreSize(SI.getValueOperand()->getType());
+  auto &DL = SI.getModule()->getDataLayout();
+  uint64_t Size = DL.getTypeStoreSize(SI.getValueOperand()->getType());
   if (Size == 0)
     return;
 
@@ -1202,7 +1252,7 @@ void DFSanVisitor::visitStoreInst(StoreInst &SI) {
   if (ClPreserveAlignment) {
     Align = SI.getAlignment();
     if (Align == 0)
-      Align = DFSF.DFS.DL->getABITypeAlignment(SI.getValueOperand()->getType());
+      Align = DL.getABITypeAlignment(SI.getValueOperand()->getType());
   } else {
     Align = 1;
   }
@@ -1293,10 +1343,10 @@ void DFSanVisitor::visitSelectInst(SelectInst &I) {
 void DFSanVisitor::visitMemSetInst(MemSetInst &I) {
   IRBuilder<> IRB(&I);
   Value *ValShadow = DFSF.getShadow(I.getValue());
-  IRB.CreateCall3(
-      DFSF.DFS.DFSanSetLabelFn, ValShadow,
-      IRB.CreateBitCast(I.getDest(), Type::getInt8PtrTy(*DFSF.DFS.Ctx)),
-      IRB.CreateZExtOrTrunc(I.getLength(), DFSF.DFS.IntptrTy));
+  IRB.CreateCall(DFSF.DFS.DFSanSetLabelFn,
+                 {ValShadow, IRB.CreateBitCast(I.getDest(), Type::getInt8PtrTy(
+                                                                *DFSF.DFS.Ctx)),
+                  IRB.CreateZExtOrTrunc(I.getLength(), DFSF.DFS.IntptrTy)});
 }
 
 void DFSanVisitor::visitMemTransferInst(MemTransferInst &I) {
@@ -1318,8 +1368,8 @@ void DFSanVisitor::visitMemTransferInst(MemTransferInst &I) {
   Type *Int8Ptr = Type::getInt8PtrTy(*DFSF.DFS.Ctx);
   DestShadow = IRB.CreateBitCast(DestShadow, Int8Ptr);
   SrcShadow = IRB.CreateBitCast(SrcShadow, Int8Ptr);
-  IRB.CreateCall5(I.getCalledValue(), DestShadow, SrcShadow, LenShadow,
-                  AlignShadow, I.getVolatileCst());
+  IRB.CreateCall(I.getCalledValue(), {DestShadow, SrcShadow, LenShadow,
+                                      AlignShadow, I.getVolatileCst()});
 }
 
 void DFSanVisitor::visitReturnInst(ReturnInst &RI) {
@@ -1352,6 +1402,15 @@ void DFSanVisitor::visitCallSite(CallSite CS) {
     return;
   }
 
+  // Calls to this function are synthesized in wrappers, and we shouldn't
+  // instrument them.
+  if (F == DFSF.DFS.DFSanVarargWrapperFn)
+    return;
+
+  assert(!(cast<FunctionType>(
+      CS.getCalledValue()->getType()->getPointerElementType())->isVarArg() &&
+           dyn_cast<InvokeInst>(CS.getInstruction())));
+
   IRBuilder<> IRB(CS.getInstruction());
 
   DenseMap<Value *, Function *>::iterator i =
@@ -1423,15 +1482,32 @@ void DFSanVisitor::visitCallSite(CallSite CS) {
         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,
+                                           CS.arg_size() - FT->getNumParams());
+          auto *LabelVAAlloca = new AllocaInst(
+              LabelVATy, "labelva", &DFSF.F->getEntryBlock().front());
+
+          for (unsigned n = 0; i != CS.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, "labelreturn",
-                               DFSF.F->getEntryBlock().begin());
+                               &DFSF.F->getEntryBlock().front());
           }
           Args.push_back(DFSF.LabelReturnAlloca);
         }
 
+        for (i = CS.arg_begin() + FT->getNumParams(); i != CS.arg_end(); ++i)
+          Args.push_back(*i);
+
         CallInst *CustomCI = IRB.CreateCall(CustomF, Args);
         CustomCI->setCallingConv(CI->getCallingConv());
         CustomCI->setAttributes(CI->getAttributes());
@@ -1463,13 +1539,14 @@ void DFSanVisitor::visitCallSite(CallSite CS) {
   if (!CS.getType()->isVoidTy()) {
     if (InvokeInst *II = dyn_cast<InvokeInst>(CS.getInstruction())) {
       if (II->getNormalDest()->getSinglePredecessor()) {
-        Next = II->getNormalDest()->begin();
+        Next = &II->getNormalDest()->front();
       } else {
         BasicBlock *NewBB =
-            SplitEdge(II->getParent(), II->getNormalDest(), &DFSF.DFS);
-        Next = NewBB->begin();
+            SplitEdge(II->getParent(), II->getNormalDest(), &DFSF.DT);
+        Next = &NewBB->front();
       }
     } else {
+      assert(CS->getIterator() != CS->getParent()->end());
       Next = CS->getNextNode();
     }
 
@@ -1502,11 +1579,12 @@ void DFSanVisitor::visitCallSite(CallSite CS) {
       unsigned VarArgSize = CS.arg_size() - FT->getNumParams();
       ArrayType *VarArgArrayTy = ArrayType::get(DFSF.DFS.ShadowTy, VarArgSize);
       AllocaInst *VarArgShadow =
-          new AllocaInst(VarArgArrayTy, "", DFSF.F->getEntryBlock().begin());
-      Args.push_back(IRB.CreateConstGEP2_32(VarArgShadow, 0, 0));
+          new AllocaInst(VarArgArrayTy, "", &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(VarArgShadow, 0, n));
+        IRB.CreateStore(
+            DFSF.getShadow(*i),
+            IRB.CreateConstGEP2_32(VarArgArrayTy, VarArgShadow, 0, n));
         Args.push_back(*i);
       }
     }
@@ -1521,8 +1599,7 @@ void DFSanVisitor::visitCallSite(CallSite CS) {
     NewCS.setCallingConv(CS.getCallingConv());
     NewCS.setAttributes(CS.getAttributes().removeAttributes(
         *DFSF.DFS.Ctx, AttributeSet::ReturnIndex,
-        AttributeFuncs::typeIncompatible(NewCS.getInstruction()->getType(),
-                                         AttributeSet::ReturnIndex)));
+        AttributeFuncs::typeIncompatible(NewCS.getInstruction()->getType())));
 
     if (Next) {
       ExtractValueInst *ExVal =