[llvm] [InstCombine] Fold extended add/sub of the same type (PR #185259)

[via llvm-commits]

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@@ -4532,6 +4532,36 @@ define <2 x i32> @ceil_div_vec_multi_use(<2 x i32> range(i32 0, 1000) %x) {
   ret <2 x i32> %r
 }
 
+define i8 @fold_to_uadd_sat_with_same_type(i8 %a, i8 %b) {
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sweiglbosker wrote:

Wrong place for these tests, should probably be in `saturating-add-sub.ll`

https://github.com/llvm/llvm-project/pull/185259