[codeview] Return type indices for typedefs

Use the type index of the underlying type unless we have a typedef from
long to HRESULT; HRESULT typedefs are translated to T_HRESULT.

llvm-svn: 271494
diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
index 41350d4..24d785b 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
+++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h
@@ -190,6 +190,7 @@
   codeview::TypeIndex getTypeIndex(DITypeRef Ty);
 
   codeview::TypeIndex lowerType(const DIType *Ty);
+  codeview::TypeIndex lowerTypeAlias(const DIDerivedType *Ty);
   codeview::TypeIndex lowerTypeBasic(const DIBasicType *Ty);
   codeview::TypeIndex lowerTypePointer(const DIDerivedType *Ty);
   codeview::TypeIndex lowerTypeMemberPointer(const DIDerivedType *Ty);