[llvm] Combine (X ^ Y) and (X == Y) where appropriate (PR #130922)

[Pengcheng Wang via llvm-commits]

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@@ -239,3 +239,43 @@ define i32 @oneusecmp(i32 %a, i32 %b, i32 %d) {
   %x = add i32 %s, %s2
   ret i32 %x
 }
+
+define i32 @xor_branch_ret(i32 %x) {
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wangpc-pp wrote:

Precommit this.

https://github.com/llvm/llvm-project/pull/130922