CHECK-LABEL-ify some code gen tests to improve diagnostic experience when tests fail.

llvm-svn: 188447
diff --git a/clang/test/CodeGen/mips-byval-arg.c b/clang/test/CodeGen/mips-byval-arg.c
index 41ccd60..589e85e 100644
--- a/clang/test/CodeGen/mips-byval-arg.c
+++ b/clang/test/CodeGen/mips-byval-arg.c
@@ -7,8 +7,8 @@
 
 extern void foo2(S0);
 
-// O32: define void @foo1(i32 %a0.coerce0, i32 %a0.coerce1, i32 %a0.coerce2)
-// N64: define void @foo1(i64 %a0.coerce0, i32 %a0.coerce1)
+// O32-LABEL: define void @foo1(i32 %a0.coerce0, i32 %a0.coerce1, i32 %a0.coerce2)
+// N64-LABEL: define void @foo1(i64 %a0.coerce0, i32 %a0.coerce1)
 
 void foo1(S0 a0) {
   foo2(a0);