[llvm] [AArch64][llvm] Redefine some insns as an alias of `SYS` (PR #187004)

[via llvm-commits]

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@@ -1773,6 +1773,11 @@ trcit x1
 // CHECK-ERROR: error: instruction requires: ite
 // CHECK-UNKNOWN:  d50b72e1      sys #3, c7, c2, #7, x1
 
+sys #3, c7, c2, #7, x2
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Lukacma wrote:

It seems we already have tests for aliases in  llvm/test/MC/AArch64/arm64-aliases.s. These kind of tests should be moved there.

https://github.com/llvm/llvm-project/pull/187004