The order of the two symbol listings in a Macho x86_64 subtractor relocation is reversed from what seems intuitive to me.

llvm-svn: 143035
diff --git a/llvm/lib/Object/MachOObjectFile.cpp b/llvm/lib/Object/MachOObjectFile.cpp
index 82b9231..97eb52d7 100644
--- a/llvm/lib/Object/MachOObjectFile.cpp
+++ b/llvm/lib/Object/MachOObjectFile.cpp
@@ -835,7 +835,9 @@
         if (error_code ec = getRelocationTargetName(RENext->Word1, SucName))
           report_fatal_error(ec.message());
 
-        fmt << Name << "-" << SucName;
+        // The X86_64_RELOC_UNSIGNED contains the minuend symbol,
+        // X86_64_SUBTRACTOR contains to the subtrahend.
+        fmt << SucName << "-" << Name;
       }
       case 6: // X86_64_RELOC_SIGNED1
         fmt << Name << "-1";