[llvm] [AArch64] Prevent reuse of retired architecture names (PR #221782)

[Jonathan Thackray via llvm-commits]

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@@ -0,0 +1,21 @@
+// RUN: not llvm-mc -triple=aarch64 -mattr=+mpamv2,+tme < %s 2>&1 | FileCheck %s
+
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jthackray wrote:

Agreed, done.

https://github.com/llvm/llvm-project/pull/221782