Be more specific about return types of some methods.

This would allow to call addCompilerUsedGlobal on some
Clang-generated globals.

llvm-svn: 212767

clang/lib/CodeGen/CodeGenModule.cpp

@@ -2770,7 +2770,7 @@ GenerateStringLiteral(llvm::Constant *C, llvm::GlobalValue::LinkageTypes LT,
 
 /// GetAddrOfConstantStringFromLiteral - Return a pointer to a
 /// constant array for the given string literal.
-llvm::Constant *
+llvm::GlobalVariable *
 CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S) {
   auto Alignment =
       getContext().getAlignOfGlobalVarInChars(S->getType()).getQuantity();
@@ -2816,7 +2816,7 @@ CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S) {
 
 /// GetAddrOfConstantStringFromObjCEncode - Return a pointer to a constant
 /// array for the given ObjCEncodeExpr node.
-llvm::Constant *
+llvm::GlobalVariable *
 CodeGenModule::GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr *E) {
   std::string Str;
   getContext().getObjCEncodingForType(E->getEncodedType(), Str);
@@ -2847,9 +2847,8 @@ llvm::StringMapEntry<llvm::GlobalVariable *> *CodeGenModule::getConstantStringMa
 /// GetAddrOfConstantCString - Returns a pointer to a character array containing
 /// the literal and a terminating '\0' character.
 /// The result has pointer to array type.
-llvm::Constant *CodeGenModule::GetAddrOfConstantCString(const std::string &Str,
-                                                        const char *GlobalName,
-                                                        unsigned Alignment) {
+llvm::GlobalVariable *CodeGenModule::GetAddrOfConstantCString(
+    const std::string &Str, const char *GlobalName, unsigned Alignment) {
   StringRef StrWithNull(Str.c_str(), Str.size() + 1);
   if (Alignment == 0) {
     Alignment = getContext()