Debug Info: define a DIRef template.

Specialize the constructors for DIRef<DIScope> and DIRef<DIType> to make sure
the Value is indeed a scope ref and a type ref.

Use DIScopeRef for DIScope::getContext and DIType::getContext and use DITypeRef
for getContainingType and getClassType.

DIScope::generateRef now returns a DIScopeRef instead of a "Value *" for
readability and type safety.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190418 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/AsmPrinter/DwarfDebug.h

@@ -684,7 +684,10 @@ public:
   unsigned getDwarfVersion() const { return DwarfVersion; }
 
   /// Find the MDNode for the given scope reference.
-  DIScope resolve(DIScopeRef SRef) const;
+  template <typename T>
+  T resolve(DIRef<T> Ref) const {
+    return Ref.resolve(TypeIdentifierMap);
+  }
 
   /// isSubprogramContext - Return true if Context is either a subprogram
   /// or another context nested inside a subprogram.