UseListOrder: Additional test coverage for r214242

r214242 was subtle enough it really deserves a targeted test with
comments.  This adds some global variables that trigger the relevant
code path.  Sorry this wasn't committed with the fix.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214243 91177308-0d34-0410-b5e6-96231b3b80d8

Author: dexonsmith

test/Bitcode/use-list-order.ll

@@ -3,6 +3,20 @@
 @a = global [4 x i1] [i1 0, i1 1, i1 0, i1 1]
 @b = alias i1* getelementptr ([4 x i1]* @a, i64 0, i64 2)
 
+; Check use-list order of constants used by globals.
+@glob1 = global i5 7
+@glob2 = global i5 7
+@glob3 = global i5 7
+
+; Check use-list order between variables and aliases.
+@target = global i3 zeroinitializer
+@alias1 = alias i3* @target
+@alias2 = alias i3* @target
+@alias3 = alias i3* @target
+@var1 = global i3* @target
+@var2 = global i3* @target
+@var3 = global i3* @target
+
 define i64 @f(i64 %f) {
 entry:
   %sum = add i64 %f, 0