[llvm] [CodeGen][AArch64] Avoid duplicate hints in register allocation (PR #219007)

[Nick Desaulniers via llvm-commits]

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@@ -0,0 +1,54 @@
+; REQUIRES: have_tf_aot
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nickdesaulniers wrote:

This test crashes at HEAD without this PR; so I'd like to keep it as an integration test demonstrating we no longer crash (in the have_tf_aot build configuration).

Let me see if I can add in addition a unittests/.  (I.e. I'd rather have _both_, as opposed to removing this .ll integration test).

https://github.com/llvm/llvm-project/pull/219007