[llvm] [AArch64] Add neon bici test for haddu and shadd (PR #84073)

[David Green via llvm-commits]

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@@ -0,0 +1,129 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
+; RUN: llc -mtriple=aarch64-neon < %s | FileCheck %s
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davemgreen wrote:

-mtriple=aarch64 should be fine.

https://github.com/llvm/llvm-project/pull/84073