[clang][NFC] GetOrCreateLLVMGlobal takes LangAS

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.

Differential Revision: https://reviews.llvm.org/D108445

Author: wingo

clang/lib/CodeGen/CGBlocks.cpp

@@ -2910,8 +2910,8 @@ 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;
 }
@@ -2920,8 +2920,8 @@ 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.cpp

@@ -2851,7 +2851,8 @@ ConstantAddress CodeGenModule::GetWeakRefReference(const ValueDecl *VD) {
                                       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);
@@ -3824,10 +3825,11 @@ bool CodeGenModule::isTypeConstant(QualType Ty, bool ExcludeCtor) {
 /// 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>())
@@ -3841,7 +3843,7 @@ CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName, llvm::Type *Ty,
     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
@@ -3865,24 +3867,23 @@ CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName, llvm::Type *Ty,
     }
 
     // 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.
@@ -4005,10 +4006,10 @@ CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName, llvm::Type *Ty,
   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;
@@ -4098,8 +4099,7 @@ llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D,
     Ty = getTypes().ConvertTypeForMem(ASTTy);
 
   StringRef MangledName = getMangledName(D);
-  return GetOrCreateLLVMGlobal(MangledName, Ty,
-                               getContext().getTargetAddressSpace(ASTTy), D,
+  return GetOrCreateLLVMGlobal(MangledName, Ty, ASTTy.getAddressSpace(), D,
                                IsForDefinition);
 }
 
@@ -4108,10 +4108,8 @@ llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D,
 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;
@@ -4528,8 +4526,8 @@ void CodeGenModule::EmitExternalVarDeclaration(const VarDecl *D) {
     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);
     }
@@ -4901,7 +4899,7 @@ void CodeGenModule::EmitAliasDefinition(GlobalDecl 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());

clang/lib/CodeGen/CodeGenModule.h

@@ -1478,8 +1478,8 @@ class CodeGenModule : public CodeGenTypeCache {
   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,