Remove the last of the special case code for emitting attributes.

This works by moving the existing code into the DIEValue hierarchy
and using the DwarfDebug pointer off of the AsmPrinter to access
any global information we need.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203033 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/AsmPrinter/DwarfDebug.h

@@ -759,6 +759,10 @@ public:
     return Ref.resolve(TypeIdentifierMap);
   }
 
+  /// Find the DwarfCompileUnit for the given CU Die.
+  DwarfCompileUnit *lookupUnit(const DIE *CU) const {
+    return CUDieMap.lookup(CU);
+  }
   /// isSubprogramContext - Return true if Context is either a subprogram
   /// or another context nested inside a subprogram.
   bool isSubprogramContext(const MDNode *Context);