[llvm] [ConstraintElim] Check the other signedness when hasSameSign (PR #128168)

[Yingwei Zheng via llvm-commits]

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@@ -303,3 +303,23 @@ define i1 @ugt_assumed_positive_values(i8 %a, i8 %b) {
 
   ret i1 %result
 }
+
+define i1 @samesign_flipped_signedness(i8 %a)  {
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dtcxzyw wrote:

Can you add the test https://github.com/llvm/llvm-project/issues/120089#issuecomment-2635581659?


https://github.com/llvm/llvm-project/pull/128168