[clang][NFC] GetOrCreateLLVMGlobal takes LangAS

[wingo]

Summary

Pass a LangAS instead of a target address space to
GetOrCreateLLVMGlobal, to remove a place where the frontend assumes that
target address space 0 is special.

[rjmccall]

LGTM

clang/lib/CodeGen/CGBlocks.cpp

configureBlocksRuntimeObject(
       *this, cast<llvm::Constant>(BlockObjectAssign.getCallee()));
   return BlockObjectAssign;
 }
 
 llvm::Constant *CodeGenModule::getNSConcreteGlobalBlock() {
   if (NSConcreteGlobalBlock)
     return NSConcreteGlobalBlock;
 
-  NSConcreteGlobalBlock =
-      GetOrCreateLLVMGlobal("_NSConcreteGlobalBlock", Int8PtrTy, 0, nullptr);
+  NSConcreteGlobalBlock = GetOrCreateLLVMGlobal(
+      "_NSConcreteGlobalBlock", Int8PtrTy, LangAS::Default, nullptr);
   configureBlocksRuntimeObject(*this, NSConcreteGlobalBlock);
   return NSConcreteGlobalBlock;
 }
 
 llvm::Constant *CodeGenModule::getNSConcreteStackBlock() {
   if (NSConcreteStackBlock)
     return NSConcreteStackBlock;
 
-  NSConcreteStackBlock =
-      GetOrCreateLLVMGlobal("_NSConcreteStackBlock", Int8PtrTy, 0, nullptr);
+  NSConcreteStackBlock = GetOrCreateLLVMGlobal(
+      "_NSConcreteStackBlock", Int8PtrTy, LangAS::Default, nullptr);
   configureBlocksRuntimeObject(*this, NSConcreteStackBlock);
   return NSConcreteStackBlock;
 }

clang/lib/CodeGen/CodeGenModule.h

llvm::Constant *GetOrCreateLLVMFunction(
       ForDefinition_t IsForDefinition = NotForDefinition);
 
   llvm::Constant *GetOrCreateMultiVersionResolver(GlobalDecl GD,
                                                   llvm::Type *DeclTy,
                                                   const FunctionDecl *FD);
   void UpdateMultiVersionNames(GlobalDecl GD, const FunctionDecl *FD);
 
   llvm::Constant *
-  GetOrCreateLLVMGlobal(StringRef MangledName, llvm::Type *Ty,
-                        unsigned AddrSpace, const VarDecl *D,
+  GetOrCreateLLVMGlobal(StringRef MangledName, llvm::Type *Ty, LangAS AddrSpace,
+                        const VarDecl *D,
                         ForDefinition_t IsForDefinition = NotForDefinition);
 
   bool GetCPUAndFeaturesAttributes(GlobalDecl GD,
                                    llvm::AttrBuilder &AttrBuilder);
   void setNonAliasAttributes(GlobalDecl GD, llvm::GlobalObject *GO);
 
   /// Set function attributes for a function declaration.
   void SetFunctionAttributes(GlobalDecl GD, llvm::Function *F,

clang/lib/CodeGen/CodeGenModule.cpp

ConstantAddress CodeGenModule::GetWeakRefReference(const ValueDecl *VD) {
   }
 
   llvm::Constant *Aliasee;
   if (isa<llvm::FunctionType>(DeclTy))
     Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy,
                                       GlobalDecl(cast<FunctionDecl>(VD)),
                                       /*ForVTable=*/false);
   else
-    Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(), DeclTy, 0, nullptr);
+    Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(), DeclTy, LangAS::Default,
+                                    nullptr);
 
   auto *F = cast<llvm::GlobalValue>(Aliasee);
   F->setLinkage(llvm::Function::ExternalWeakLinkage);
   WeakRefReferences.insert(F);
 
   return ConstantAddress(Aliasee, Alignment);
 }
 

 /// If D is non-null, it specifies a decl that correspond to this.  This is used
 /// to set the attributes on the global when it is first created.
 ///
 /// If IsForDefinition is true, it is guaranteed that an actual global with
 /// type Ty will be returned, not conversion of a variable with the same
 /// mangled name but some other type.
 llvm::Constant *
 CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName, llvm::Type *Ty,
-                                     unsigned AddrSpace, const VarDecl *D,
+                                     LangAS AddrSpace, const VarDecl *D,
                                      ForDefinition_t IsForDefinition) {
   // Lookup the entry, lazily creating it if necessary.
   llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
+  unsigned TargetAS = getContext().getTargetAddressSpace(AddrSpace);
   if (Entry) {
     if (WeakRefReferences.erase(Entry)) {
       if (D && !D->hasAttr<WeakAttr>())
         Entry->setLinkage(llvm::Function::ExternalLinkage);
     }
 
     // Handle dropped DLL attributes.
     if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>())
       Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
 
     if (LangOpts.OpenMP && !LangOpts.OpenMPSimd && D)
       getOpenMPRuntime().registerTargetGlobalVariable(D, Entry);
 
-    if (Entry->getValueType() == Ty && Entry->getAddressSpace() == AddrSpace)
+    if (Entry->getValueType() == Ty && Entry->getAddressSpace() == TargetAS)
       return Entry;
 
     // If there are two attempts to define the same mangled name, issue an
     // error.
     if (IsForDefinition && !Entry->isDeclaration()) {
       GlobalDecl OtherGD;
       const VarDecl *OtherD;
 
       // Check that D is not yet in DiagnosedConflictingDefinitions is required
       // to make sure that we issue an error only once.
       if (D && lookupRepresentativeDecl(MangledName, OtherGD) &&
           (D->getCanonicalDecl() != OtherGD.getCanonicalDecl().getDecl()) &&
           (OtherD = dyn_cast<VarDecl>(OtherGD.getDecl())) &&
           OtherD->hasInit() &&
           DiagnosedConflictingDefinitions.insert(D).second) {
         getDiags().Report(D->getLocation(), diag::err_duplicate_mangled_name)
             << MangledName;
         getDiags().Report(OtherGD.getDecl()->getLocation(),
                           diag::note_previous_definition);
       }
     }
 
     // Make sure the result is of the correct type.
-    if (Entry->getType()->getAddressSpace() != AddrSpace) {
+    if (Entry->getType()->getAddressSpace() != TargetAS) {
       return llvm::ConstantExpr::getAddrSpaceCast(Entry,
-                                                  Ty->getPointerTo(AddrSpace));
+                                                  Ty->getPointerTo(TargetAS));
     }
 
     // (If global is requested for a definition, we always need to create a new
     // global, not just return a bitcast.)
     if (!IsForDefinition)
-      return llvm::ConstantExpr::getBitCast(Entry, Ty->getPointerTo(AddrSpace));
+      return llvm::ConstantExpr::getBitCast(Entry, Ty->getPointerTo(TargetAS));
   }
 
   auto DAddrSpace = GetGlobalVarAddressSpace(D);
-  auto TargetAddrSpace = getContext().getTargetAddressSpace(DAddrSpace);
 
   auto *GV = new llvm::GlobalVariable(
       getModule(), Ty, false, llvm::GlobalValue::ExternalLinkage, nullptr,
       MangledName, nullptr, llvm::GlobalVariable::NotThreadLocal,
-      TargetAddrSpace);
+      getContext().getTargetAddressSpace(DAddrSpace));
 
   // If we already created a global with the same mangled name (but different
   // type) before, take its name and remove it from its parent.
   if (Entry) {
     GV->takeName(Entry);
 
     if (!Entry->use_empty()) {
       llvm::Constant *NewPtrForOldDecl =
if (GV->isDeclaration()) {
     if (getLangOpts().CUDA && D && D->hasAttr<HIPManagedAttr>() &&
         D->hasExternalStorage())
       getCUDARuntime().handleVarRegistration(D, *GV);
   }
 
   LangAS ExpectedAS =
       D ? D->getType().getAddressSpace()
         : (LangOpts.OpenCL ? LangAS::opencl_global : LangAS::Default);
-  assert(getContext().getTargetAddressSpace(ExpectedAS) == AddrSpace);
+  assert(getContext().getTargetAddressSpace(ExpectedAS) == TargetAS);
   if (DAddrSpace != ExpectedAS) {
     return getTargetCodeGenInfo().performAddrSpaceCast(
-        *this, GV, DAddrSpace, ExpectedAS, Ty->getPointerTo(AddrSpace));
+        *this, GV, DAddrSpace, ExpectedAS, Ty->getPointerTo(TargetAS));
   }
 
   return GV;
 }
 
 llvm::Constant *
 CodeGenModule::GetAddrOfGlobal(GlobalDecl GD, ForDefinition_t IsForDefinition) {
   const Decl *D = GD.getDecl();
llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D,
                                                   llvm::Type *Ty,
                                            ForDefinition_t IsForDefinition) {
   assert(D->hasGlobalStorage() && "Not a global variable");
   QualType ASTTy = D->getType();
   if (!Ty)
     Ty = getTypes().ConvertTypeForMem(ASTTy);
 
   StringRef MangledName = getMangledName(D);
-  return GetOrCreateLLVMGlobal(MangledName, Ty,
-                               getContext().getTargetAddressSpace(ASTTy), D,
+  return GetOrCreateLLVMGlobal(MangledName, Ty, ASTTy.getAddressSpace(), D,
                                IsForDefinition);
 }
 
 /// CreateRuntimeVariable - Create a new runtime global variable with the
 /// specified type and name.
 llvm::Constant *
 CodeGenModule::CreateRuntimeVariable(llvm::Type *Ty,
                                      StringRef Name) {
-  auto AddrSpace =
-      getContext().getLangOpts().OpenCL
-          ? getContext().getTargetAddressSpace(LangAS::opencl_global)
-          : 0;
+  LangAS AddrSpace = getContext().getLangOpts().OpenCL ? LangAS::opencl_global
+                                                       : LangAS::Default;
   auto *Ret = GetOrCreateLLVMGlobal(Name, Ty, AddrSpace, nullptr);
   setDSOLocal(cast<llvm::GlobalValue>(Ret->stripPointerCasts()));
   return Ret;
 }
 
 void CodeGenModule::EmitTentativeDefinition(const VarDecl *D) {
   assert(!D->getInit() && "Cannot emit definite definitions here!");
 
if (getCodeGenOpts().hasReducedDebugInfo())
       DI->EmitGlobalVariable(GV, D);
 }
 
 void CodeGenModule::EmitExternalVarDeclaration(const VarDecl *D) {
   if (CGDebugInfo *DI = getModuleDebugInfo())
     if (getCodeGenOpts().hasReducedDebugInfo()) {
       QualType ASTTy = D->getType();
       llvm::Type *Ty = getTypes().ConvertTypeForMem(D->getType());
-      llvm::Constant *GV = GetOrCreateLLVMGlobal(
-          D->getName(), Ty, getContext().getTargetAddressSpace(ASTTy), D);
+      llvm::Constant *GV =
+          GetOrCreateLLVMGlobal(D->getName(), Ty, ASTTy.getAddressSpace(), D);
       DI->EmitExternalVariable(
           cast<llvm::GlobalVariable>(GV->stripPointerCasts()), D);
     }
 }
 
 static bool isVarDeclStrongDefinition(const ASTContext &Context,
                                       CodeGenModule &CGM, const VarDecl *D,
                                       bool NoCommon) {
void CodeGenModule::EmitAliasDefinition(GlobalDecl GD) {
   // if a deferred decl.
   llvm::Constant *Aliasee;
   llvm::GlobalValue::LinkageTypes LT;
   if (isa<llvm::FunctionType>(DeclTy)) {
     Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, GD,
                                       /*ForVTable=*/false);
     LT = getFunctionLinkage(GD);
   } else {
-    Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(), DeclTy, 0,
+    Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(), DeclTy, LangAS::Default,
                                     /*D=*/nullptr);
     if (const auto *VD = dyn_cast<VarDecl>(GD.getDecl()))
       LT = getLLVMLinkageVarDefinition(VD, D->getType().isConstQualified());
     else
       LT = getFunctionLinkage(GD);
   }
 
   // Create the new alias itself, but don't set a name yet.