Load from GV stub should be locally CSE'd.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55763 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86FastISel.cpp b/lib/Target/X86/X86FastISel.cpp
index 9b784b4..38aa994 100644
--- a/lib/Target/X86/X86FastISel.cpp
+++ b/lib/Target/X86/X86FastISel.cpp
@@ -71,6 +71,8 @@
     X86AddressMode AM;
     AM.GV = GV;
     addFullAddress(BuildMI(MBB, TII.get(Opc), Op0), AM);
+    // Prevent loading GV stub multiple times in same MBB.
+    LocalValueMap[V] = Op0;
   }
   return true;
 }