x86_64 ABI: Tweak merging algorithm so that we always bail early when
we see a Memory classification.

llvm-svn: 63295
diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index 6ffe8c3..afdf57a 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -548,13 +548,13 @@
       //
       // (f) Otherwise class SSE is used.
       if (Target == FieldLo || FieldLo == NoClass) ;
-      else if (Target == NoClass)
-        Target = FieldLo;
       else if (FieldLo == Memory) {
         // Memory is never over-ridden, just bail.
         Lo = Memory;
         return;
       } 
+      else if (Target == NoClass)
+        Target = FieldLo;
       else if (Target == Integer || FieldLo == Integer) 
         Target = Integer;
       else if (FieldLo == X87 || FieldLo == X87Up || FieldLo == ComplexX87) {