IR: Give function GlobalValue::getRealLinkageName() a less misleading name: getPGOName().

[pcc]

Summary

This function gives the wrong answer on some non-ELF platforms in some
cases. The function that does the right thing lives in Mangler.h. To try to
discourage people from using this function, give it a different name.

Yes, this introduces calls to a function named getPGOName() in code that
has nothing to do with PGO, but don't shoot the messenger.

[mehdi_amini]

Most of the uses reads quite wrong since it has nothing to do with PGO. I'm not fond of this renaming right now, can we find another alternative name?

llvm/include/llvm/IR/GlobalValue.h

446

Is this still up to date? How does it play with the getPGOName name and the rest of the comment?

[pcc]

Most of the uses reads quite wrong since it has nothing to do with PGO.

Yes, that's the point :)

Use of a function named getPGOName() in code that has nothing to do with PGO stands out and makes it more obvious that there is a bug. Using a "better" name would increase the chance of the function being used incorrectly in other places.

llvm/include/llvm/IR/GlobalValue.h

446

That part of the comment is still technically accurate, if a little misleading. I'll reword it.

[mehdi_amini]

In D33162#754180, @pcc wrote:

Most of the uses reads quite wrong since it has nothing to do with PGO.

Yes, that's the point :)

Use of a function named getPGOName() in code that has nothing to do with PGO stands out and makes it more obvious that there is a bug. Using a "better" name would increase the chance of the function being used incorrectly in other places.

What is the plan for all these uses your updating in this patch? Why don't you change these to use the "right" thing?

[pcc]

In D33162#754183, @mehdi_amini wrote:

In D33162#754180, @pcc wrote:

Most of the uses reads quite wrong since it has nothing to do with PGO.

Yes, that's the point :)

Use of a function named getPGOName() in code that has nothing to do with PGO stands out and makes it more obvious that there is a bug. Using a "better" name would increase the chance of the function being used incorrectly in other places.

What is the plan for all these uses your updating in this patch? Why don't you change these to use the "right" thing?

I wasn't planning to do that, I just wanted to make a change to prevent accidental use of this function, which I think is better than the status quo.

[rnk]

In D33162#754180, @pcc wrote:

Most of the uses reads quite wrong since it has nothing to do with PGO.

Yes, that's the point :)

Use of a function named getPGOName() in code that has nothing to do with PGO stands out and makes it more obvious that there is a bug. Using a "better" name would increase the chance of the function being used incorrectly in other places.

Let's go ahead and try to come up with a better name without solving the real problem. I'd focus on something really mechanical, since this is truly a low-level mechanical function. If you really want the object file name, you need DataLayout. Actually, why not fold Mangler into DataLayout? Mangler::getNameWithPrefix doesn't use any instance variables.

Anyway, I nominate something like dropLLVMManglingEscape. In contexts like DiagnosticInfo.cpp it should be clear to the reader that this is correct. In contexts like ASan, DataLayout should be available and we should use it.

[pcc]

• Rename and reword a comment

[pcc]

In D33162#755514, @rnk wrote:

In D33162#754180, @pcc wrote:

Most of the uses reads quite wrong since it has nothing to do with PGO.

Yes, that's the point :)

Use of a function named getPGOName() in code that has nothing to do with PGO stands out and makes it more obvious that there is a bug. Using a "better" name would increase the chance of the function being used incorrectly in other places.

Let's go ahead and try to come up with a better name without solving the real problem. I'd focus on something really mechanical, since this is truly a low-level mechanical function. If you really want the object file name, you need DataLayout. Actually, why not fold Mangler into DataLayout? Mangler::getNameWithPrefix doesn't use any instance variables.

Anyway, I nominate something like dropLLVMManglingEscape. In contexts like DiagnosticInfo.cpp it should be clear to the reader that this is correct. In contexts like ASan, DataLayout should be available and we should use it.

That name works for me; done.

[rnk]

lgtm, ship it

[mehdi_amini]

(thanks, with this naming it looks better to me!)

llvm/include/llvm/IR/GlobalValue.h

 protected:
   /// Copy all additional attributes (those not needed to create a GlobalValue)
   /// from the GlobalValue Src to this one.
   void copyAttributesFrom(const GlobalValue *Src);
 
 public:
   /// If special LLVM prefix that is used to inform the asm printer to not emit
   /// usual symbol prefix before the symbol name is used then return linkage
   /// name after skipping this special LLVM prefix.
-  static StringRef getRealLinkageName(StringRef Name) {
+  ///
+  /// This function applies a specific mangling that is used in PGO profiles,
+  /// among other things. If you're trying to get a symbol name for an
+  /// arbitrary GlobalValue, this is not the function you're looking for; see
+  /// Mangler.h.
+  static StringRef getPGOName(StringRef Name) {
     if (!Name.empty() && Name[0] == '\1')
       return Name.substr(1);
     return Name;
   }
 
   /// Return the modified name for a global value suitable to be
   /// used as the key for a global lookup (e.g. profile or ThinLTO).
   /// The value's original name is \c Name and has linkage of type

llvm/lib/Analysis/OptimizationDiagnosticInfo.cpp

void MappingTraits<DiagnosticInfoOptimizationBase *>::mapping(
   else if (io.mapTag("!Failure", OptDiag->getKind() == DK_OptimizationFailure))
     ;
   else
     llvm_unreachable("Unknown remark type");
 
   // These are read-only for now.
   DiagnosticLocation DL = OptDiag->getLocation();
   StringRef FN =
-      GlobalValue::getRealLinkageName(OptDiag->getFunction().getName());
+      GlobalValue::getPGOName(OptDiag->getFunction().getName());
 
   StringRef PassName(OptDiag->PassName);
   io.mapRequired("Pass", PassName);
   io.mapRequired("Name", OptDiag->RemarkName);
   if (!io.outputting() || DL.isValid())
     io.mapOptional("DebugLoc", DL);
   io.mapRequired("Function", FN);
   io.mapOptional("Hotness", OptDiag->Hotness);

llvm/lib/Analysis/TargetLibraryInfo.cpp

 static StringRef sanitizeFunctionName(StringRef funcName) {
   // Filter out empty names and names containing null bytes, those can't be in
   // our table.
   if (funcName.empty() || funcName.find('\0') != StringRef::npos)
     return StringRef();
 
   // Check for \01 prefix that is used to mangle __asm declarations and
   // strip it if present.
-  return GlobalValue::getRealLinkageName(funcName);
+  return GlobalValue::getPGOName(funcName);
 }
 
 bool TargetLibraryInfoImpl::getLibFunc(StringRef funcName,
                                        LibFunc &F) const {
   StringRef const *Start = &StandardNames[0];
   StringRef const *End = &StandardNames[NumLibFuncs];
 
   funcName = sanitizeFunctionName(funcName);

llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp

void CodeViewDebug::emitDebugInfoForFunction(const Function *GV,
   // If we have a display name, build the fully qualified name by walking the
   // chain of scopes.
   if (!SP->getName().empty())
     FuncName =
         getFullyQualifiedName(SP->getScope().resolve(), SP->getName());
 
   // If our DISubprogram name is empty, use the mangled name.
   if (FuncName.empty())
-    FuncName = GlobalValue::getRealLinkageName(GV->getName());
+    FuncName = GlobalValue::getPGOName(GV->getName());
 
   // Emit a symbol subsection, required by VS2012+ to find function boundaries.
   OS.AddComment("Symbol subsection for " + Twine(FuncName));
   MCSymbol *SymbolsEnd = beginCVSubsection(ModuleDebugFragmentKind::Symbols);
   {
     MCSymbol *ProcRecordBegin = MMI->getContext().createTempSymbol(),
              *ProcRecordEnd = MMI->getContext().createTempSymbol();
     OS.AddComment("Record length");
for (const MDNode *Node : CUs->operands()) {
 
     // Second, emit each global that is in a comdat into its own .debug$S
     // section along with its own symbol substream.
     for (const auto *GVE : CU->getGlobalVariables()) {
       if (const auto *GV = GlobalMap.lookup(GVE)) {
         if (GV->hasComdat()) {
           MCSymbol *GVSym = Asm->getSymbol(GV);
           OS.AddComment("Symbol subsection for " +
-                        Twine(GlobalValue::getRealLinkageName(GV->getName())));
+                        Twine(GlobalValue::getPGOName(GV->getName())));
           switchToDebugSectionForSymbol(GVSym);
           EndLabel = beginCVSubsection(ModuleDebugFragmentKind::Symbols);
           // FIXME: emitDebugInfoForGlobal() doesn't handle DIExpressions.
           emitDebugInfoForGlobal(GVE->getVariable(), GV, GVSym);
           endCVSubsection(EndLabel);
         }
       }
     }

llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp

void DwarfUnit::addConstantValue(DIE &Die, const APInt &Val, bool Unsigned) {
   addBlock(Die, dwarf::DW_AT_const_value, Block);
 }
 
 void DwarfUnit::addLinkageName(DIE &Die, StringRef LinkageName) {
   if (!LinkageName.empty())
     addString(Die,
               DD->getDwarfVersion() >= 4 ? dwarf::DW_AT_linkage_name
                                          : dwarf::DW_AT_MIPS_linkage_name,
-              GlobalValue::getRealLinkageName(LinkageName));
+              GlobalValue::getPGOName(LinkageName));
 }
 
 void DwarfUnit::addTemplateParams(DIE &Buffer, DINodeArray TParams) {
   // Add template parameters.
   for (const auto *Element : TParams) {
     if (auto *TTP = dyn_cast<DITemplateTypeParameter>(Element))
       constructTemplateTypeParameterDIE(Buffer, TTP);
     else if (auto *TVP = dyn_cast<DITemplateValueParameter>(Element))

llvm/lib/CodeGen/AsmPrinter/WinException.cpp

void WinException::beginFunction(const MachineFunction *MF) {
   // might want EH tables if we had EH pads.
   if (!Asm->MAI->usesWindowsCFI()) {
     if (Per == EHPersonality::MSVC_X86SEH && !hasEHFunclets) {
       // If this is 32-bit SEH and we don't have any funclets (really invokes),
       // make sure we emit the parent offset label. Some unreferenced filter
       // functions may still refer to it.
       const WinEHFuncInfo &FuncInfo = *MF->getWinEHFuncInfo();
       StringRef FLinkageName =
-          GlobalValue::getRealLinkageName(MF->getFunction()->getName());
+          GlobalValue::getPGOName(MF->getFunction()->getName());
       emitEHRegistrationOffsetLabel(FuncInfo, FLinkageName);
     }
     shouldEmitLSDA = hasEHFunclets;
     shouldEmitPersonality = false;
     return;
   }
 
   beginFunclet(MF->front(), Asm->CurrentFnSym);
if (!MBB)
     return nullptr;
 
   assert(MBB->isEHFuncletEntry());
 
   // Give catches and cleanups a name based off of their parent function and
   // their funclet entry block's number.
   const MachineFunction *MF = MBB->getParent();
   const Function *F = MF->getFunction();
-  StringRef FuncLinkageName = GlobalValue::getRealLinkageName(F->getName());
+  StringRef FuncLinkageName = GlobalValue::getPGOName(F->getName());
   MCContext &Ctx = MF->getContext();
   StringRef HandlerPrefix = MBB->isCleanupFuncletEntry() ? "dtor" : "catch";
   return Ctx.getOrCreateSymbol("?" + HandlerPrefix + "$" +
                                Twine(MBB->getNumber()) + "@?0?" +
                                FuncLinkageName + "@4HA");
 }
 
 void WinException::beginFunclet(const MachineBasicBlock &MBB,
if (shouldEmitMoves || shouldEmitPersonality) {
 
     // Emit an UNWIND_INFO struct describing the prologue.
     Asm->OutStreamer->EmitWinEHHandlerData();
 
     if (Per == EHPersonality::MSVC_CXX && shouldEmitPersonality &&
         !CurrentFuncletEntry->isCleanupFuncletEntry()) {
       // If this is a C++ catch funclet (or the parent function),
       // emit a reference to the LSDA for the parent function.
-      StringRef FuncLinkageName = GlobalValue::getRealLinkageName(F->getName());
+      StringRef FuncLinkageName = GlobalValue::getPGOName(F->getName());
       MCSymbol *FuncInfoXData = Asm->OutContext.getOrCreateSymbol(
           Twine("$cppxdata$", FuncLinkageName));
       Asm->OutStreamer->EmitValue(create32bitRef(FuncInfoXData), 4);
     } else if (Per == EHPersonality::MSVC_Win64SEH && MF->hasEHFunclets() &&
                !CurrentFuncletEntry->isEHFuncletEntry()) {
       // If this is the parent function in Win64 SEH, emit the LSDA immediately
       // following .seh_handlerdata.
       emitCSpecificHandlerTable(MF);
void WinException::emitCSpecificHandlerTable(const MachineFunction *MF) {
   auto AddComment = [&](const Twine &Comment) {
     if (VerboseAsm)
       OS.AddComment(Comment);
   };
 
   // Emit a label assignment with the SEH frame offset so we can use it for
   // llvm.x86.seh.recoverfp.
   StringRef FLinkageName =
-      GlobalValue::getRealLinkageName(MF->getFunction()->getName());
+      GlobalValue::getPGOName(MF->getFunction()->getName());
   MCSymbol *ParentFrameOffset =
       Ctx.getOrCreateParentFrameOffsetSymbol(FLinkageName);
   const MCExpr *MCOffset =
       MCConstantExpr::create(FuncInfo.SEHSetFrameOffset, Ctx);
   Asm->OutStreamer->EmitAssignment(ParentFrameOffset, MCOffset);
 
   // Use the assembler to compute the number of table entries through label
   // difference and division.
void WinException::emitSEHActionsForRange(const WinEHFuncInfo &FuncInfo,
   }
 }
 
 void WinException::emitCXXFrameHandler3Table(const MachineFunction *MF) {
   const Function *F = MF->getFunction();
   auto &OS = *Asm->OutStreamer;
   const WinEHFuncInfo &FuncInfo = *MF->getWinEHFuncInfo();
 
-  StringRef FuncLinkageName = GlobalValue::getRealLinkageName(F->getName());
+  StringRef FuncLinkageName = GlobalValue::getPGOName(F->getName());
 
   SmallVector<std::pair<const MCExpr *, int>, 4> IPToStateTable;
   MCSymbol *FuncInfoXData = nullptr;
   if (shouldEmitPersonality) {
     // If we're 64-bit, emit a pointer to the C++ EH data, and build a map from
     // IPs to state numbers.
     FuncInfoXData =
         Asm->OutContext.getOrCreateSymbol(Twine("$cppxdata$", FuncLinkageName));

 }
 
 /// Emit the language-specific data that _except_handler3 and 4 expect. This is
 /// functionally equivalent to the __C_specific_handler table, except it is
 /// indexed by state number instead of IP.
 void WinException::emitExceptHandlerTable(const MachineFunction *MF) {
   MCStreamer &OS = *Asm->OutStreamer;
   const Function *F = MF->getFunction();
-  StringRef FLinkageName = GlobalValue::getRealLinkageName(F->getName());
+  StringRef FLinkageName = GlobalValue::getPGOName(F->getName());
 
   bool VerboseAsm = OS.isVerboseAsm();
   auto AddComment = [&](const Twine &Comment) {
     if (VerboseAsm)
       OS.AddComment(Comment);
   };
 
   const WinEHFuncInfo &FuncInfo = *MF->getWinEHFuncInfo();

llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

for (unsigned Idx = 0, E = I.getNumArgOperands(); Idx < E; ++Idx) {
       if (isa<ConstantPointerNull>(Arg))
         continue; // Skip null pointers. They represent a hole in index space.
       AllocaInst *Slot = cast<AllocaInst>(Arg);
       assert(FuncInfo.StaticAllocaMap.count(Slot) &&
              "can only escape static allocas");
       int FI = FuncInfo.StaticAllocaMap[Slot];
       MCSymbol *FrameAllocSym =
           MF.getMMI().getContext().getOrCreateFrameAllocSymbol(
-              GlobalValue::getRealLinkageName(MF.getName()), Idx);
+              GlobalValue::getPGOName(MF.getName()), Idx);
       BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, dl,
               TII->get(TargetOpcode::LOCAL_ESCAPE))
           .addSym(FrameAllocSym)
           .addFrameIndex(FI);
     }
 
     return nullptr;
   }
 
   case Intrinsic::localrecover: {
     // i8* @llvm.localrecover(i8* %fn, i8* %fp, i32 %idx)
     MachineFunction &MF = DAG.getMachineFunction();
     MVT PtrVT = TLI.getPointerTy(DAG.getDataLayout(), 0);
 
     // Get the symbol that defines the frame offset.
     auto *Fn = cast<Function>(I.getArgOperand(0)->stripPointerCasts());
     auto *Idx = cast<ConstantInt>(I.getArgOperand(2));
     unsigned IdxVal = unsigned(Idx->getLimitedValue(INT_MAX));
     MCSymbol *FrameAllocSym =
         MF.getMMI().getContext().getOrCreateFrameAllocSymbol(
-            GlobalValue::getRealLinkageName(Fn->getName()), IdxVal);
+            GlobalValue::getPGOName(Fn->getName()), IdxVal);
 
     // Create a MCSymbol for the label to avoid any target lowering
     // that would make this PC relative.
     SDValue OffsetSym = DAG.getMCSymbol(FrameAllocSym, PtrVT);
     SDValue OffsetVal =
         DAG.getNode(ISD::LOCAL_RECOVER, sdl, PtrVT, OffsetSym);
 
     // Add the offset to the FP.

llvm/lib/IR/DiagnosticInfo.cpp

if (DISubprogram *SP = F->getSubprogram())
       Loc = SP;
   }
   else if (auto *I = dyn_cast<Instruction>(V))
     Loc = I->getDebugLoc();
 
   // Only include names that correspond to user variables.  FIXME: we should use
   // debug info if available to get the name of the user variable.
   if (isa<llvm::Argument>(V) || isa<GlobalValue>(V))
-    Val = GlobalValue::getRealLinkageName(V->getName());
+    Val = GlobalValue::getPGOName(V->getName());
   else if (isa<Constant>(V)) {
     raw_string_ostream OS(Val);
     V->printAsOperand(OS, /*PrintType=*/false);
   } else if (auto *I = dyn_cast<Instruction>(V))
     Val = I->getOpcodeName();
 }
 
 DiagnosticInfoOptimizationBase::Argument::Argument(StringRef Key, const Type *T)

llvm/lib/LTO/LTO.cpp

if (Conf.OptLevel > 0) {
     // Compute "dead" symbols, we don't want to import/export these!
     DenseSet<GlobalValue::GUID> GUIDPreservedSymbols;
     for (auto &Res : GlobalResolutions) {
       if (Res.second.VisibleOutsideThinLTO &&
           // IRName will be defined if we have seen the prevailing copy of
           // this value. If not, no need to preserve any ThinLTO copies.
           !Res.second.IRName.empty())
         GUIDPreservedSymbols.insert(GlobalValue::getGUID(
-            GlobalValue::getRealLinkageName(Res.second.IRName)));
+            GlobalValue::getPGOName(Res.second.IRName)));
     }
 
     auto DeadSymbols =
         computeDeadSymbols(ThinLTO.CombinedIndex, GUIDPreservedSymbols);
 
     ComputeCrossModuleImport(ThinLTO.CombinedIndex, ModuleToDefinedGVSummaries,
                              ImportLists, ExportLists, &DeadSymbols);
 
     std::set<GlobalValue::GUID> ExportedGUIDs;
     for (auto &Res : GlobalResolutions) {
       // First check if the symbol was flagged as having external references.
       if (Res.second.Partition != GlobalResolution::External)
         continue;
       // IRName will be defined if we have seen the prevailing copy of
       // this value. If not, no need to mark as exported from a ThinLTO
       // partition (and we can't get the GUID).
       if (Res.second.IRName.empty())
         continue;
       auto GUID = GlobalValue::getGUID(
-          GlobalValue::getRealLinkageName(Res.second.IRName));
+          GlobalValue::getPGOName(Res.second.IRName));
       // Mark exported unless index-based analysis determined it to be dead.
       if (!DeadSymbols.count(GUID))
         ExportedGUIDs.insert(GUID);
     }
 
     auto isPrevailing = [&](GlobalValue::GUID GUID,
                             const GlobalValueSummary *S) {
       return ThinLTO.PrevailingModuleForGUID[GUID] == S->modulePath();

llvm/lib/Target/X86/X86ISelLowering.cpp

static SDValue recoverFramePointer(SelectionDAG &DAG, const Function *Fn,
   // the incoming EBP.
   if (!Fn->hasPersonalityFn())
     return EntryEBP;
 
   // Get an MCSymbol that will ultimately resolve to the frame offset of the EH
   // registration, or the .set_setframe offset.
   MCSymbol *OffsetSym =
       MF.getMMI().getContext().getOrCreateParentFrameOffsetSymbol(
-          GlobalValue::getRealLinkageName(Fn->getName()));
+          GlobalValue::getPGOName(Fn->getName()));
   SDValue OffsetSymVal = DAG.getMCSymbol(OffsetSym, PtrVT);
   SDValue ParentFrameOffset =
       DAG.getNode(ISD::LOCAL_RECOVER, dl, PtrVT, OffsetSymVal);
 
   // Return EntryEBP + ParentFrameOffset for x64. This adjusts from RSP after
   // prologue to RBP in the parent function.
   const X86Subtarget &Subtarget =
       static_cast<const X86Subtarget &>(DAG.getSubtarget());
static SDValue LowerINTRINSIC_WO_CHAIN(SDValue Op, const X86Subtarget &Subtarget,
   }
 
   case Intrinsic::x86_seh_lsda: {
     // Compute the symbol for the LSDA. We know it'll get emitted later.
     MachineFunction &MF = DAG.getMachineFunction();
     SDValue Op1 = Op.getOperand(1);
     auto *Fn = cast<Function>(cast<GlobalAddressSDNode>(Op1)->getGlobal());
     MCSymbol *LSDASym = MF.getMMI().getContext().getOrCreateLSDASymbol(
-        GlobalValue::getRealLinkageName(Fn->getName()));
+        GlobalValue::getPGOName(Fn->getName()));
 
     // Generate a simple absolute symbol reference. This intrinsic is only
     // supported on 32-bit Windows, which isn't PIC.
     SDValue Result = DAG.getMCSymbol(LSDASym, VT);
     return DAG.getNode(X86ISD::Wrapper, dl, VT, Result);
   }
 
   case Intrinsic::x86_seh_recoverfp: {

llvm/lib/Target/X86/X86WinEHState.cpp

Function *WinEHStatePass::generateLSDAInEAXThunk(Function *ParentFunc) {
   FunctionType *TrampolineTy =
       FunctionType::get(Int32Ty, makeArrayRef(&ArgTys[0], 4),
                         /*isVarArg=*/false);
   FunctionType *TargetFuncTy =
       FunctionType::get(Int32Ty, makeArrayRef(&ArgTys[0], 5),
                         /*isVarArg=*/false);
   Function *Trampoline =
       Function::Create(TrampolineTy, GlobalValue::InternalLinkage,
-                       Twine("__ehhandler$") + GlobalValue::getRealLinkageName(
+                       Twine("__ehhandler$") + GlobalValue::getPGOName(
                                                    ParentFunc->getName()),
                        TheModule);
   BasicBlock *EntryBB = BasicBlock::Create(Context, "entry", Trampoline);
   IRBuilder<> Builder(EntryBB);
   Value *LSDA = emitEHLSDA(Builder, ParentFunc);
   Value *CastPersonality =
       Builder.CreateBitCast(PersonalityFn, TargetFuncTy->getPointerTo());
   auto AI = Trampoline->arg_begin();

llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp

 GlobalVariable *
 AddressSanitizerModule::CreateMetadataGlobal(Module &M, Constant *Initializer,
                                              StringRef OriginalName) {
   auto Linkage = TargetTriple.isOSBinFormatMachO()
                      ? GlobalVariable::InternalLinkage
                      : GlobalVariable::PrivateLinkage;
   GlobalVariable *Metadata = new GlobalVariable(
       M, Initializer->getType(), false, Linkage, Initializer,
-      Twine("__asan_global_") + GlobalValue::getRealLinkageName(OriginalName));
+      Twine("__asan_global_") + GlobalValue::getPGOName(OriginalName));
   Metadata->setSection(getGlobalMetadataSection());
   return Metadata;
 }
 
 IRBuilder<> AddressSanitizerModule::CreateAsanModuleDtor(Module &M) {
   AsanDtorFunction =
       Function::Create(FunctionType::get(Type::getVoidTy(*C), false),
                        GlobalValue::InternalLinkage, kAsanModuleDtorName, &M);