1 files changed, 282 insertions, 125 deletions

diff --git a/lib/Transforms/Instrumentation/InstrProfiling.cpp b/lib/Transforms/Instrumentation/InstrProfiling.cpp
index 28483e7e9b692..b11c6be696f3e 100644
--- a/lib/Transforms/Instrumentation/InstrProfiling.cpp
+++ b/lib/Transforms/Instrumentation/InstrProfiling.cpp
@@ -13,12 +13,12 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/Transforms/InstrProfiling.h"
 #include "llvm/ADT/Triple.h"
 #include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/Module.h"
 #include "llvm/ProfileData/InstrProf.h"
-#include "llvm/Transforms/Instrumentation.h"
 #include "llvm/Transforms/Utils/ModuleUtils.h"
 
 using namespace llvm;
@@ -27,121 +27,112 @@ using namespace llvm;
 
 namespace {
 
-class InstrProfiling : public ModulePass {
+cl::opt<bool> DoNameCompression("enable-name-compression",
+                                cl::desc("Enable name string compression"),
+                                cl::init(true));
+
+cl::opt<bool> ValueProfileStaticAlloc(
+    "vp-static-alloc",
+    cl::desc("Do static counter allocation for value profiler"),
+    cl::init(true));
+cl::opt<double> NumCountersPerValueSite(
+    "vp-counters-per-site",
+    cl::desc("The average number of profile counters allocated "
+             "per value profiling site."),
+    // This is set to a very small value because in real programs, only
+    // a very small percentage of value sites have non-zero targets, e.g, 1/30.
+    // For those sites with non-zero profile, the average number of targets
+    // is usually smaller than 2.
+    cl::init(1.0));
+
+class InstrProfilingLegacyPass : public ModulePass {
+  InstrProfiling InstrProf;
+
 public:
   static char ID;
-
-  InstrProfiling() : ModulePass(ID) {}
-
-  InstrProfiling(const InstrProfOptions &Options)
-      : ModulePass(ID), Options(Options) {}
-
+  InstrProfilingLegacyPass() : ModulePass(ID), InstrProf() {}
+  InstrProfilingLegacyPass(const InstrProfOptions &Options)
+      : ModulePass(ID), InstrProf(Options) {}
   const char *getPassName() const override {
     return "Frontend instrumentation-based coverage lowering";
   }
 
-  bool runOnModule(Module &M) override;
+  bool runOnModule(Module &M) override { return InstrProf.run(M); }
 
   void getAnalysisUsage(AnalysisUsage &AU) const override {
     AU.setPreservesCFG();
   }
+};
 
-private:
-  InstrProfOptions Options;
-  Module *M;
-  typedef struct PerFunctionProfileData {
-    uint32_t NumValueSites[IPVK_Last+1];
-    GlobalVariable* RegionCounters;
-    GlobalVariable* DataVar;
-    PerFunctionProfileData() : RegionCounters(nullptr), DataVar(nullptr) {
-      memset(NumValueSites, 0, sizeof(uint32_t) * (IPVK_Last+1));
-    }
-  } PerFunctionProfileData;
-  DenseMap<GlobalVariable *, PerFunctionProfileData> ProfileDataMap;
-  std::vector<Value *> UsedVars;
-
-  bool isMachO() const {
-    return Triple(M->getTargetTriple()).isOSBinFormatMachO();
-  }
-
-  /// Get the section name for the counter variables.
-  StringRef getCountersSection() const {
-    return getInstrProfCountersSectionName(isMachO());
-  }
-
-  /// Get the section name for the name variables.
-  StringRef getNameSection() const {
-    return getInstrProfNameSectionName(isMachO());
-  }
-
-  /// Get the section name for the profile data variables.
-  StringRef getDataSection() const {
-    return getInstrProfDataSectionName(isMachO());
-  }
-
-  /// Get the section name for the coverage mapping data.
-  StringRef getCoverageSection() const {
-    return getInstrProfCoverageSectionName(isMachO());
-  }
-
-  /// Count the number of instrumented value sites for the function.
-  void computeNumValueSiteCounts(InstrProfValueProfileInst *Ins);
-
-  /// Replace instrprof_value_profile with a call to runtime library.
-  void lowerValueProfileInst(InstrProfValueProfileInst *Ins);
-
-  /// Replace instrprof_increment with an increment of the appropriate value.
-  void lowerIncrement(InstrProfIncrementInst *Inc);
+} // anonymous namespace
 
-  /// Force emitting of name vars for unused functions.
-  void lowerCoverageData(GlobalVariable *CoverageNamesVar);
+PreservedAnalyses InstrProfiling::run(Module &M, AnalysisManager<Module> &AM) {
+  if (!run(M))
+    return PreservedAnalyses::all();
 
-  /// Get the region counters for an increment, creating them if necessary.
-  ///
-  /// If the counter array doesn't yet exist, the profile data variables
-  /// referring to them will also be created.
-  GlobalVariable *getOrCreateRegionCounters(InstrProfIncrementInst *Inc);
+  return PreservedAnalyses::none();
+}
 
-  /// Emit runtime registration functions for each profile data variable.
-  void emitRegistration();
+char InstrProfilingLegacyPass::ID = 0;
+INITIALIZE_PASS(InstrProfilingLegacyPass, "instrprof",
+                "Frontend instrumentation-based coverage lowering.", false,
+                false)
 
-  /// Emit the necessary plumbing to pull in the runtime initialization.
-  void emitRuntimeHook();
+ModulePass *
+llvm::createInstrProfilingLegacyPass(const InstrProfOptions &Options) {
+  return new InstrProfilingLegacyPass(Options);
+}
 
-  /// Add uses of our data variables and runtime hook.
-  void emitUses();
+bool InstrProfiling::isMachO() const {
+  return Triple(M->getTargetTriple()).isOSBinFormatMachO();
+}
 
-  /// Create a static initializer for our data, on platforms that need it,
-  /// and for any profile output file that was specified.
-  void emitInitialization();
-};
+/// Get the section name for the counter variables.
+StringRef InstrProfiling::getCountersSection() const {
+  return getInstrProfCountersSectionName(isMachO());
+}
 
-} // anonymous namespace
+/// Get the section name for the name variables.
+StringRef InstrProfiling::getNameSection() const {
+  return getInstrProfNameSectionName(isMachO());
+}
 
-char InstrProfiling::ID = 0;
-INITIALIZE_PASS(InstrProfiling, "instrprof",
-                "Frontend instrumentation-based coverage lowering.", false,
-                false)
+/// Get the section name for the profile data variables.
+StringRef InstrProfiling::getDataSection() const {
+  return getInstrProfDataSectionName(isMachO());
+}
 
-ModulePass *llvm::createInstrProfilingPass(const InstrProfOptions &Options) {
-  return new InstrProfiling(Options);
+/// Get the section name for the coverage mapping data.
+StringRef InstrProfiling::getCoverageSection() const {
+  return getInstrProfCoverageSectionName(isMachO());
 }
 
-bool InstrProfiling::runOnModule(Module &M) {
+bool InstrProfiling::run(Module &M) {
   bool MadeChange = false;
 
   this->M = &M;
+  NamesVar = nullptr;
+  NamesSize = 0;
   ProfileDataMap.clear();
   UsedVars.clear();
 
   // We did not know how many value sites there would be inside
   // the instrumented function. This is counting the number of instrumented
   // target value sites to enter it as field in the profile data variable.
-  for (Function &F : M)
+  for (Function &F : M) {
+    InstrProfIncrementInst *FirstProfIncInst = nullptr;
     for (BasicBlock &BB : F)
-      for (auto I = BB.begin(), E = BB.end(); I != E;)
-        if (auto *Ind = dyn_cast<InstrProfValueProfileInst>(I++))
+      for (auto I = BB.begin(), E = BB.end(); I != E; I++)
+        if (auto *Ind = dyn_cast<InstrProfValueProfileInst>(I))
           computeNumValueSiteCounts(Ind);
+        else if (FirstProfIncInst == nullptr)
+          FirstProfIncInst = dyn_cast<InstrProfIncrementInst>(I);
+
+    // Value profiling intrinsic lowering requires per-function profile data
+    // variable to be created first.
+    if (FirstProfIncInst != nullptr)
+      static_cast<void>(getOrCreateRegionCounters(FirstProfIncInst));
+  }
 
   for (Function &F : M)
     for (BasicBlock &BB : F)
@@ -157,7 +148,7 @@ bool InstrProfiling::runOnModule(Module &M) {
       }
 
   if (GlobalVariable *CoverageNamesVar =
-          M.getNamedGlobal(getCoverageNamesVarName())) {
+          M.getNamedGlobal(getCoverageUnusedNamesVarName())) {
     lowerCoverageData(CoverageNamesVar);
     MadeChange = true;
   }
@@ -165,6 +156,8 @@ bool InstrProfiling::runOnModule(Module &M) {
   if (!MadeChange)
     return false;
 
+  emitVNodes();
+  emitNameData();
   emitRegistration();
   emitRuntimeHook();
   emitUses();
@@ -204,7 +197,7 @@ void InstrProfiling::lowerValueProfileInst(InstrProfValueProfileInst *Ind) {
   GlobalVariable *Name = Ind->getName();
   auto It = ProfileDataMap.find(Name);
   assert(It != ProfileDataMap.end() && It->second.DataVar &&
-    "value profiling detected in function with no counter incerement");
+         "value profiling detected in function with no counter incerement");
 
   GlobalVariable *DataVar = It->second.DataVar;
   uint64_t ValueKind = Ind->getValueKind()->getZExtValue();
@@ -213,9 +206,9 @@ void InstrProfiling::lowerValueProfileInst(InstrProfValueProfileInst *Ind) {
     Index += It->second.NumValueSites[Kind];
 
   IRBuilder<> Builder(Ind);
-  Value* Args[3] = {Ind->getTargetValue(),
-      Builder.CreateBitCast(DataVar, Builder.getInt8PtrTy()),
-      Builder.getInt32(Index)};
+  Value *Args[3] = {Ind->getTargetValue(),
+                    Builder.CreateBitCast(DataVar, Builder.getInt8PtrTy()),
+                    Builder.getInt32(Index)};
   Ind->replaceAllUsesWith(
       Builder.CreateCall(getOrInsertValueProfilingCall(*M), Args));
   Ind->eraseFromParent();
@@ -243,9 +236,8 @@ void InstrProfiling::lowerCoverageData(GlobalVariable *CoverageNamesVar) {
     assert(isa<GlobalVariable>(V) && "Missing reference to function name");
     GlobalVariable *Name = cast<GlobalVariable>(V);
 
-    // Move the name variable to the right section.
-    Name->setSection(getNameSection());
-    Name->setAlignment(1);
+    Name->setLinkage(GlobalValue::PrivateLinkage);
+    ReferencedNames.push_back(Name);
   }
 }
 
@@ -261,22 +253,77 @@ static inline bool shouldRecordFunctionAddr(Function *F) {
   if (!F->hasLinkOnceLinkage() && !F->hasLocalLinkage() &&
       !F->hasAvailableExternallyLinkage())
     return true;
+  // Prohibit function address recording if the function is both internal and
+  // COMDAT. This avoids the profile data variable referencing internal symbols
+  // in COMDAT.
+  if (F->hasLocalLinkage() && F->hasComdat())
+    return false;
   // Check uses of this function for other than direct calls or invokes to it.
-  return F->hasAddressTaken();
+  // Inline virtual functions have linkeOnceODR linkage. When a key method
+  // exists, the vtable will only be emitted in the TU where the key method
+  // is defined. In a TU where vtable is not available, the function won't
+  // be 'addresstaken'. If its address is not recorded here, the profile data
+  // with missing address may be picked by the linker leading  to missing
+  // indirect call target info.
+  return F->hasAddressTaken() || F->hasLinkOnceLinkage();
+}
+
+static inline bool needsComdatForCounter(Function &F, Module &M) {
+
+  if (F.hasComdat())
+    return true;
+
+  Triple TT(M.getTargetTriple());
+  if (!TT.isOSBinFormatELF())
+    return false;
+
+  // See createPGOFuncNameVar for more details. To avoid link errors, profile
+  // counters for function with available_externally linkage needs to be changed
+  // to linkonce linkage. On ELF based systems, this leads to weak symbols to be
+  // created. Without using comdat, duplicate entries won't be removed by the
+  // linker leading to increased data segement size and raw profile size. Even
+  // worse, since the referenced counter from profile per-function data object
+  // will be resolved to the common strong definition, the profile counts for
+  // available_externally functions will end up being duplicated in raw profile
+  // data. This can result in distorted profile as the counts of those dups
+  // will be accumulated by the profile merger.
+  GlobalValue::LinkageTypes Linkage = F.getLinkage();
+  if (Linkage != GlobalValue::ExternalWeakLinkage &&
+      Linkage != GlobalValue::AvailableExternallyLinkage)
+    return false;
+
+  return true;
 }
 
-static inline Comdat *getOrCreateProfileComdat(Module &M,
+static inline Comdat *getOrCreateProfileComdat(Module &M, Function &F,
                                                InstrProfIncrementInst *Inc) {
+  if (!needsComdatForCounter(F, M))
+    return nullptr;
+
   // COFF format requires a COMDAT section to have a key symbol with the same
-  // name. The linker targeting COFF also requires that the COMDAT section
+  // name. The linker targeting COFF also requires that the COMDAT
   // a section is associated to must precede the associating section. For this
-  // reason, we must choose the name var's name as the name of the comdat.
+  // reason, we must choose the counter var's name as the name of the comdat.
   StringRef ComdatPrefix = (Triple(M.getTargetTriple()).isOSBinFormatCOFF()
-                                ? getInstrProfNameVarPrefix()
+                                ? getInstrProfCountersVarPrefix()
                                 : getInstrProfComdatPrefix());
   return M.getOrInsertComdat(StringRef(getVarName(Inc, ComdatPrefix)));
 }
 
+static bool needsRuntimeRegistrationOfSectionRange(const Module &M) {
+  // Don't do this for Darwin.  compiler-rt uses linker magic.
+  if (Triple(M.getTargetTriple()).isOSDarwin())
+    return false;
+
+  // Use linker script magic to get data/cnts/name start/end.
+  if (Triple(M.getTargetTriple()).isOSLinux() ||
+      Triple(M.getTargetTriple()).isOSFreeBSD() ||
+      Triple(M.getTargetTriple()).isPS4CPU())
+    return false;
+
+  return true;
+}
+
 GlobalVariable *
 InstrProfiling::getOrCreateRegionCounters(InstrProfIncrementInst *Inc) {
   GlobalVariable *NamePtr = Inc->getName();
@@ -294,11 +341,7 @@ InstrProfiling::getOrCreateRegionCounters(InstrProfIncrementInst *Inc) {
   // linking.
   Function *Fn = Inc->getParent()->getParent();
   Comdat *ProfileVarsComdat = nullptr;
-  if (Fn->hasComdat())
-    ProfileVarsComdat = getOrCreateProfileComdat(*M, Inc);
-  NamePtr->setSection(getNameSection());
-  NamePtr->setAlignment(1);
-  NamePtr->setComdat(ProfileVarsComdat);
+  ProfileVarsComdat = getOrCreateProfileComdat(*M, *Fn, Inc);
 
   uint64_t NumCounters = Inc->getNumCounters()->getZExtValue();
   LLVMContext &Ctx = M->getContext();
@@ -314,27 +357,51 @@ InstrProfiling::getOrCreateRegionCounters(InstrProfIncrementInst *Inc) {
   CounterPtr->setAlignment(8);
   CounterPtr->setComdat(ProfileVarsComdat);
 
-  // Create data variable.
   auto *Int8PtrTy = Type::getInt8PtrTy(Ctx);
+  // Allocate statically the array of pointers to value profile nodes for
+  // the current function.
+  Constant *ValuesPtrExpr = ConstantPointerNull::get(Int8PtrTy);
+  if (ValueProfileStaticAlloc && !needsRuntimeRegistrationOfSectionRange(*M)) {
+
+    uint64_t NS = 0;
+    for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind)
+      NS += PD.NumValueSites[Kind];
+    if (NS) {
+      ArrayType *ValuesTy = ArrayType::get(Type::getInt64Ty(Ctx), NS);
+
+      auto *ValuesVar =
+          new GlobalVariable(*M, ValuesTy, false, NamePtr->getLinkage(),
+                             Constant::getNullValue(ValuesTy),
+                             getVarName(Inc, getInstrProfValuesVarPrefix()));
+      ValuesVar->setVisibility(NamePtr->getVisibility());
+      ValuesVar->setSection(getInstrProfValuesSectionName(isMachO()));
+      ValuesVar->setAlignment(8);
+      ValuesVar->setComdat(ProfileVarsComdat);
+      ValuesPtrExpr =
+          ConstantExpr::getBitCast(ValuesVar, llvm::Type::getInt8PtrTy(Ctx));
+    }
+  }
+
+  // Create data variable.
   auto *Int16Ty = Type::getInt16Ty(Ctx);
-  auto *Int16ArrayTy = ArrayType::get(Int16Ty, IPVK_Last+1);
+  auto *Int16ArrayTy = ArrayType::get(Int16Ty, IPVK_Last + 1);
   Type *DataTypes[] = {
-    #define INSTR_PROF_DATA(Type, LLVMType, Name, Init) LLVMType,
-    #include "llvm/ProfileData/InstrProfData.inc"
+#define INSTR_PROF_DATA(Type, LLVMType, Name, Init) LLVMType,
+#include "llvm/ProfileData/InstrProfData.inc"
   };
   auto *DataTy = StructType::get(Ctx, makeArrayRef(DataTypes));
 
-  Constant *FunctionAddr = shouldRecordFunctionAddr(Fn) ?
-                           ConstantExpr::getBitCast(Fn, Int8PtrTy) :
-                           ConstantPointerNull::get(Int8PtrTy);
+  Constant *FunctionAddr = shouldRecordFunctionAddr(Fn)
+                               ? ConstantExpr::getBitCast(Fn, Int8PtrTy)
+                               : ConstantPointerNull::get(Int8PtrTy);
 
-  Constant *Int16ArrayVals[IPVK_Last+1];
+  Constant *Int16ArrayVals[IPVK_Last + 1];
   for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind)
     Int16ArrayVals[Kind] = ConstantInt::get(Int16Ty, PD.NumValueSites[Kind]);
 
   Constant *DataVals[] = {
-    #define INSTR_PROF_DATA(Type, LLVMType, Name, Init) Init,
-    #include "llvm/ProfileData/InstrProfData.inc"
+#define INSTR_PROF_DATA(Type, LLVMType, Name, Init) Init,
+#include "llvm/ProfileData/InstrProfData.inc"
   };
   auto *Data = new GlobalVariable(*M, DataTy, false, NamePtr->getLinkage(),
                                   ConstantStruct::get(DataTy, DataVals),
@@ -350,28 +417,99 @@ InstrProfiling::getOrCreateRegionCounters(InstrProfIncrementInst *Inc) {
 
   // Mark the data variable as used so that it isn't stripped out.
   UsedVars.push_back(Data);
+  // Now that the linkage set by the FE has been passed to the data and counter
+  // variables, reset Name variable's linkage and visibility to private so that
+  // it can be removed later by the compiler.
+  NamePtr->setLinkage(GlobalValue::PrivateLinkage);
+  // Collect the referenced names to be used by emitNameData.
+  ReferencedNames.push_back(NamePtr);
 
   return CounterPtr;
 }
 
-void InstrProfiling::emitRegistration() {
-  // Don't do this for Darwin.  compiler-rt uses linker magic.
-  if (Triple(M->getTargetTriple()).isOSDarwin())
+void InstrProfiling::emitVNodes() {
+  if (!ValueProfileStaticAlloc)
     return;
 
-  // Use linker script magic to get data/cnts/name start/end.
-  if (Triple(M->getTargetTriple()).isOSLinux() ||
-      Triple(M->getTargetTriple()).isOSFreeBSD())
+  // For now only support this on platforms that do
+  // not require runtime registration to discover
+  // named section start/end.
+  if (needsRuntimeRegistrationOfSectionRange(*M))
+    return;
+
+  size_t TotalNS = 0;
+  for (auto &PD : ProfileDataMap) {
+    for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind)
+      TotalNS += PD.second.NumValueSites[Kind];
+  }
+
+  if (!TotalNS)
+    return;
+
+  uint64_t NumCounters = TotalNS * NumCountersPerValueSite;
+// Heuristic for small programs with very few total value sites.
+// The default value of vp-counters-per-site is chosen based on
+// the observation that large apps usually have a low percentage
+// of value sites that actually have any profile data, and thus
+// the average number of counters per site is low. For small
+// apps with very few sites, this may not be true. Bump up the
+// number of counters in this case.
+#define INSTR_PROF_MIN_VAL_COUNTS 10
+  if (NumCounters < INSTR_PROF_MIN_VAL_COUNTS)
+    NumCounters = std::max(INSTR_PROF_MIN_VAL_COUNTS, (int)NumCounters * 2);
+
+  auto &Ctx = M->getContext();
+  Type *VNodeTypes[] = {
+#define INSTR_PROF_VALUE_NODE(Type, LLVMType, Name, Init) LLVMType,
+#include "llvm/ProfileData/InstrProfData.inc"
+  };
+  auto *VNodeTy = StructType::get(Ctx, makeArrayRef(VNodeTypes));
+
+  ArrayType *VNodesTy = ArrayType::get(VNodeTy, NumCounters);
+  auto *VNodesVar = new GlobalVariable(
+      *M, VNodesTy, false, llvm::GlobalValue::PrivateLinkage,
+      Constant::getNullValue(VNodesTy), getInstrProfVNodesVarName());
+  VNodesVar->setSection(getInstrProfVNodesSectionName(isMachO()));
+  UsedVars.push_back(VNodesVar);
+}
+
+void InstrProfiling::emitNameData() {
+  std::string UncompressedData;
+
+  if (ReferencedNames.empty())
+    return;
+
+  std::string CompressedNameStr;
+  if (Error E = collectPGOFuncNameStrings(ReferencedNames, CompressedNameStr,
+                                          DoNameCompression)) {
+    llvm::report_fatal_error(toString(std::move(E)), false);
+  }
+
+  auto &Ctx = M->getContext();
+  auto *NamesVal = llvm::ConstantDataArray::getString(
+      Ctx, StringRef(CompressedNameStr), false);
+  NamesVar = new llvm::GlobalVariable(*M, NamesVal->getType(), true,
+                                      llvm::GlobalValue::PrivateLinkage,
+                                      NamesVal, getInstrProfNamesVarName());
+  NamesSize = CompressedNameStr.size();
+  NamesVar->setSection(getNameSection());
+  UsedVars.push_back(NamesVar);
+}
+
+void InstrProfiling::emitRegistration() {
+  if (!needsRuntimeRegistrationOfSectionRange(*M))
     return;
 
   // Construct the function.
   auto *VoidTy = Type::getVoidTy(M->getContext());
   auto *VoidPtrTy = Type::getInt8PtrTy(M->getContext());
+  auto *Int64Ty = Type::getInt64Ty(M->getContext());
   auto *RegisterFTy = FunctionType::get(VoidTy, false);
   auto *RegisterF = Function::Create(RegisterFTy, GlobalValue::InternalLinkage,
                                      getInstrProfRegFuncsName(), M);
-  RegisterF->setUnnamedAddr(true);
-  if (Options.NoRedZone) RegisterF->addFnAttr(Attribute::NoRedZone);
+  RegisterF->setUnnamedAddr(GlobalValue::UnnamedAddr::Global);
+  if (Options.NoRedZone)
+    RegisterF->addFnAttr(Attribute::NoRedZone);
 
   auto *RuntimeRegisterTy = FunctionType::get(VoidTy, VoidPtrTy, false);
   auto *RuntimeRegisterF =
@@ -380,7 +518,20 @@ void InstrProfiling::emitRegistration() {
 
   IRBuilder<> IRB(BasicBlock::Create(M->getContext(), "", RegisterF));
   for (Value *Data : UsedVars)
-    IRB.CreateCall(RuntimeRegisterF, IRB.CreateBitCast(Data, VoidPtrTy));
+    if (Data != NamesVar)
+      IRB.CreateCall(RuntimeRegisterF, IRB.CreateBitCast(Data, VoidPtrTy));
+
+  if (NamesVar) {
+    Type *ParamTypes[] = {VoidPtrTy, Int64Ty};
+    auto *NamesRegisterTy =
+        FunctionType::get(VoidTy, makeArrayRef(ParamTypes), false);
+    auto *NamesRegisterF =
+        Function::Create(NamesRegisterTy, GlobalVariable::ExternalLinkage,
+                         getInstrProfNamesRegFuncName(), M);
+    IRB.CreateCall(NamesRegisterF, {IRB.CreateBitCast(NamesVar, VoidPtrTy),
+                                    IRB.getInt64(NamesSize)});
+  }
+
   IRB.CreateRetVoid();
 }
 
@@ -392,7 +543,8 @@ void InstrProfiling::emitRuntimeHook() {
     return;
 
   // If the module's provided its own runtime, we don't need to do anything.
-  if (M->getGlobalVariable(getInstrProfRuntimeHookVarName())) return;
+  if (M->getGlobalVariable(getInstrProfRuntimeHookVarName()))
+    return;
 
   // Declare an external variable that will pull in the runtime initialization.
   auto *Int32Ty = Type::getInt32Ty(M->getContext());
@@ -405,8 +557,11 @@ void InstrProfiling::emitRuntimeHook() {
                                 GlobalValue::LinkOnceODRLinkage,
                                 getInstrProfRuntimeHookVarUseFuncName(), M);
   User->addFnAttr(Attribute::NoInline);
-  if (Options.NoRedZone) User->addFnAttr(Attribute::NoRedZone);
+  if (Options.NoRedZone)
+    User->addFnAttr(Attribute::NoRedZone);
   User->setVisibility(GlobalValue::HiddenVisibility);
+  if (Triple(M->getTargetTriple()).supportsCOMDAT())
+    User->setComdat(M->getOrInsertComdat(User->getName()));
 
   IRBuilder<> IRB(BasicBlock::Create(M->getContext(), "", User));
   auto *Load = IRB.CreateLoad(Var);
@@ -448,16 +603,18 @@ void InstrProfiling::emitInitialization() {
   std::string InstrProfileOutput = Options.InstrProfileOutput;
 
   Constant *RegisterF = M->getFunction(getInstrProfRegFuncsName());
-  if (!RegisterF && InstrProfileOutput.empty()) return;
+  if (!RegisterF && InstrProfileOutput.empty())
+    return;
 
   // Create the initialization function.
   auto *VoidTy = Type::getVoidTy(M->getContext());
   auto *F = Function::Create(FunctionType::get(VoidTy, false),
                              GlobalValue::InternalLinkage,
                              getInstrProfInitFuncName(), M);
-  F->setUnnamedAddr(true);
+  F->setUnnamedAddr(GlobalValue::UnnamedAddr::Global);
   F->addFnAttr(Attribute::NoInline);
-  if (Options.NoRedZone) F->addFnAttr(Attribute::NoRedZone);
+  if (Options.NoRedZone)
+    F->addFnAttr(Attribute::NoRedZone);
 
   // Add the basic block and the necessary calls.
   IRBuilder<> IRB(BasicBlock::Create(M->getContext(), "", F));